Britbike forum

1928 Ariel Model C

Posted By: Magnetoman

1928 Ariel Model C - 04/10/17 11:36 pm

An edited and illustrated version of the following appeared in the August 2018 issue of the Ariel Owners Motor Cycle Club (AOMCC) magazine Cheval de Fer. For anyone coming to this thread for the first time it serves as a ~1500-word "Executive Summary" of what follows in the 1400+ posts that currently total the equivalent of 250+ single-spaced pages of text.

"Executive Summary" of this Thread

Background
At the time of this writing in early July 2018 the start of the two-week, 3750-mile, cross-U.S. Cannonball ride is less than two months away. Eighteen months ago I was one of approximately 110 people from a large pool of applicants who were informed they had succeeded in obtaining entries for this event, which is for machines built prior to 1929. However, that posed an immediate problem since I didn't own a machine old enough to qualify.

Harleys and Indians are a dime a dozen in the U.S. (well, more like $30k+, but still relatively common), so they make up the bulk of the entries. However, I've ridden British bikes "forever" so I wanted one of them, if for no other reason than to be on something different. Making a long story short, after three months of following dead-end leads, a 1928 Model C Ariel that was collecting dust at a friend's house in Dublin revealed itself and soon was on an airplane headed to me.

I've never had an Ariel before, but it has a special appeal because it was designed by Val Page and I have three of his later BSA Gold Stars and even have written a book about these machines. Although the dealer sold the Ariel to my friend as having been restored, and externally it was in great condition, I fully expected I would have to rebuild it myself, which is what I spent the next year doing. In the course of this I found that although some of the mechanical work had been done correctly, there were so many bodges that the bike would have failed within a few hundred miles. So, over the past year I've restored the bike down to the last nut and bolt.

Starting the Rebuild
The first problem I faced in the rebuild was there appeared to be essentially no technical information on this machine. But, I slowly started collecting photocopies of whatever little I could find and, starting from nothing, my "shop manual" has grown into two binders holding nearly 700 pages and with tabs separating the material into appropriate sections. Also, I measured every piece that came off the bike to create a 'General Data' section that's now 8 pages long. In hot rodding terms I "blueprinted" the Ariel, but in many cases that required first figuring out what the original specifications would have been.

My original plan was to ride the bike for a while before rebuilding it but before I realized what was happening it somehow found itself on the lift with enough parts removed that the restoration was underway. Here I'll only touch on some of the highlights, but my rebuild is extensively documented on the web in the equivalent of over 250 single-spaced pages. Search for the words Britbike and 1928 Ariel to find it.

The first "major" task I undertook was to fabricate brackets for a headlamp, which has an unusual mount consisting of tapered lugs on the forks. For this I machined a die from a large block of Al and used it with my 30T press to form stainless tube into the necessary 'S' shape, brazed them to tapered end pieces I had made to fit the lugs, and pressed flats into the end with a form to give a curve where the flat portion meets the rounded tube. The forks then came apart so I could Magnaflux them and do repair work on the spindles and bushes. The steering damper assembly was a rusty mess that didn't fit so it took some machining to set things right. I turned both drums on the mill, which were a fair bit out of round, and new high performance brake linings are properly arced to the measured IDs of both.

The Engine
With the forks and wheels taken care of it was time for the engine. Thanks to finding two people who had original pistons and rings to weigh I was able to calculate the factory's original balance factor which I then used with a new Omega piston. I machined a torque plate for the cylinder, which my measurements showed made a significant difference, and then used it while boring and honing the cylinder for the +0.060" piston. I machined and honed the valve guides from G2 Gray Iron and made a new timing-side bush from phosphor bronze for the crankshaft and line-bored it on the mill. In case it's not already obvious, considerable precision machining was needed to restore this "restored" motorcycle.

The recess in the case for the drive-side bearing was oval so I took off enough material to make it round and then plated Cu on the new bearing to give it the necessary press fit. The pushrods were in bad shape so I made a set of new ones using CrMo tubing along with welding and grinding Stellite to shape for the ends. The connecting rod was slightly bent so it took two jigs and several trips back and forth between the press and surface plate to get the small end accurately parallel with the crankshaft.

Although the cam faces themselves were fine, both ends of the camshaft were in bad shape so I masked most of the component, plated the ends with hard chrome, and then used a tool post grinder to remove the excess. I then made bushes from phosphor bronze of appropriate ID to match. I took the time to machine a "universal" crankshaft assembly jig for pressing the two halves of a singles crankshaft together in close alignment (to minimize the need for adjustment) since such a jig would be useful for other rebuilds in the future. I also very accurately aligned the crankshaft axis on the milling machine and faced the crankcase mouth parallel to it.

Turning to the head, measurements showed significant distortion of the valve seats when the head was torqued so I used the torque plate with a cylindrical spacer against the sealing surface when cutting the seats for new valves. I used Neway cutters and did 4-angle jobs on both seats. The faces of the rockers were in bad shape so I made a jig to rotate them at the correct radius and used the toolpost grinder to recondition them.

Gearbox Issues
Once the engine was assembled and back in the frame it was time for the gearbox. It is stamped 'QL' so when I saw an advertisement in the December 2017 Cheval de Fer for new QH gear sets I immediately ordered a set. Unfortunately for me, when I finally got to the point of opening the gearbox I found it already had QH gears in it. Oh well. The main issue with the gearbox was the open-ended bush at one end of the layshaft was enlarged so grease and oil would have easily oozed out so I made a blind bush to replace it. I also made a spacer/baffle from Teflon for a gear on the mainshaft in the hopes it would slow oil exiting via that route into the kickstarter housing.

With the gearbox back together attaching the drive gear proved more work than it should have. Aftermarket gears are flat, rather than with the necessary spacer/hub as part of them. Although that is easy to solve by machining a separate spacer, I discovered that aftermarket gears are broached incorrectly and don't fit on the splines, forcing me to spend time with a file to hand fit the sprocket to the gearbox.

Final Assembly
Once the gears were sorted out and the bike reassembled, which requires dealing with a myriad of associated details, it was time to start it. It started and ran great, except for the oiling system. Making another long story short, the plunger of the oil pump had excessive clearance so I rebuilt it with a new plunger I fabricated from W1 tool steel and with necessary clearances obtained with Sunnen internal and external hones. I also needed to wind my own replacement spring since the spacing between the plunger and housing doesn't allow for any standard spring I could find.

As of this writing the last task is to completely rebuild the magneto. The magneto is working now so I'm using it on shakedown runs, but shortly will temporarily swap it for a rebuilt magdyno so I can continue those runs while working on the magneto. Before the middle of August the Ariel along with necessary tools, spares, and supplies has to be crated and on its way to Portland, Maine for the initial events starting September 4 so the clock is ticking.

Final Note
Like many (most? all?) commercial restorations, the Ariel's beauty was only skin deep when I got it. However, thousands of dollars and countless hours later, this "restored" Ariel now actually is restored. Stay tuned to find out if it has a trouble-free ride across the U.S. in September, or if I overlooked something critical.

-----------------------
This forum has very low activity so starting this thread represents true optimism.

A 1928 500cc Ariel Model C is on its way to me to ride in the 2018 Cannonball which takes place in ~17 months. Although the bike is complete and "restored," all too often restorations are only skin deep so I will completely rebuild it myself. In preparing to do this I've assembled my own ~250-page "shop manual" by gathering and organizing technical information from a wide variety of sources (e.g. D. Barkshire's Black Ariels, G.S. Davison's The Book of the Ariel, the Owners' Guide, Burman manuals, the relevant posts on the Ariel owners' club forum, etc.).

With the above as brief background, and after having gone through all the information I could find, I am left with a number of questions. In no particular order, what is:

-- the balance factor?
-- the connecting rod length?
-- the free length and diameter of the valve springs?
-- the head diameter, stem diameter, and length of the inlet and exhaust valves?
-- the carburetor size (i.e. ID of the inlet tract)?
-- a modern spark plug for this bike?
-- the number of teeth on the rear sprocket?
-- a modern grease to use in the gearbox?
-- a modern equivalent for "Crimsangere" grease?
-- the diameter and number of steering head balls?

Of course, I'll be able to answer many of these questions for myself once the bike arrives and is in pieces. However, I plan to ride it for a while to learn its idiosyncrasies before disassembling it, and the 17 months will pass quickly, so I'd like to get as much of a head start on this as I can.


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Posted By: robcurrie

Re: Technical questions: 1928 Ariel Model C - 04/11/17 2:17 am

Hi MM,

I checked what the pre-war AJS & Matchless guys are using and it seems like either Penrite or Morris Lubricants semi-fluid grease is the right stuff for Burman gearboxes. Crimsangere appears to be similar, but developed for Sturmey Archer 'boxes. Recommendations are to add an "eggcup" of 50 wt oil to the grease.

These are listed on the Classic-oils.net website.

Rob C
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/11/17 3:48 am

Originally Posted by robcurrie
either Penrite or Morris Lubricants semi-fluid grease is the right stuff for Burman gearboxes.
Thanks very much for this information.

Penrite seems to be nearly unavailable in the U.S. but I've sent an email to the one place I can find who supplies it. If they do handle it I guess I should buy a lifetime's supply.
Posted By: kevin roberts

Re: Technical questions: 1928 Ariel Model C - 04/11/17 1:37 pm

your lifetime or your ariel's?

your bike has a running start on you.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/11/17 3:02 pm

Originally Posted by kevin roberts
your lifetime or your ariel's?
There are actuarial tables for the former but not the latter so the best I can do is stock up on enough oil to see me through to my end. After that, the Ariel will have to find its own Penrite distributor.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/11/17 5:37 pm

The grease thickens. One might think the issue of "grease" is a simple one, but the more I look into it, the less I know. The contemporary grease recommendations for the Ariel were:

Gearbox:
Castrolease Light
Mobilubricant Extra Soft

For all other uses:
Crimsangere Light
Mobilubricant Soft
Castrolease Light

Unfortunately, there is essentially no information to be found for any of these on the web, let alone recommendations for modern equivalents. It appears Castrol L/EPO might be appropriate for the gearbox, but it doesn't appear to be sold in the U.S. Sometimes seemingly-simple problems take the longest to solve. Sigh...
Posted By: Adam M.

Re: Technical questions: 1928 Ariel Model C - 04/11/17 6:47 pm

Check Royal Enfield forum - older indian bikes are also using some kind of grease in their gearboxes.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/11/17 7:47 pm

Originally Posted by Adam M.
Check Royal Enfield forum
Other bikes used Burman gearboxes as well, but I'm hoping for an "authoritative" recommendation for the best equivalent modern liquid grease. I've sent queries to Morris Lubricants and Castrol and am waiting to hear back from them, as well as from the Penrite distributor in the U.S.
Posted By: gREgg-K

Re: Technical questions: 1928 Ariel Model C - 04/11/17 8:32 pm

Originally Posted by Magnetoman
Originally Posted by Adam M.
Check Royal Enfield forum
<SNIP> but I'm hoping for an "authoritative" recommendation for the best equivalent modern liquid grease. I've sent queries to Morris Lubricants and Castrol and am waiting to hear back from them, as well as from the Penrite distributor in the U.S.

I know several Henderson riders had gearbox failures on the Cannonball. I never did learn whether it was caused by an inappropriate lubricant, but the pictures I saw of the repeat failures sure looked like it.

I'm thinking that one of them must have sorted out a suitable lubricant since then.

.. Gregg
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/11/17 11:18 pm

Originally Posted by gREgg-K
I know several Henderson riders had gearbox failures on the Cannonball.
It would be easy to decide that any lubricant is way better than no lubricant and ignore this question. But, lubricants actually do matter, even in 90-year old gearboxes. For example, some additives attack bronze bushings and if a grease is too thick it will cavitate and result in inadequate lubrication. I hadn't heard of the Henderson problem but in light of issues like these it isn't surprising.


Posted By: gavin eisler

Re: Technical questions: 1928 Ariel Model C - 04/11/17 11:39 pm

AFAIK older gearboxes used a high viscosity lube due to poor sealing, typically a mix 50:50 of axle grease and a heavy oil, this would sort of set up at rest and not leak too dramatically. Castrol changed lube names regularly, none of the oil specced for our plant in the 60s had the same names but had modern equivalents, maybe some old records are left at Castrol. Seagull outboard engines use a very heavy gear oil EP 140, , something like that mixed with the mineral grease of choice may be a good compromise if the exact stuff isnt available anymore. Modern seals mean that lubes that set up when it cools down are no longer required. It may be possible to fit sealed bearings to your Ariel gearbox if the sizes arent too weird, meaning you could possibly use real oil rather than runny grease.
Posted By: Triless

Re: Technical questions: 1928 Ariel Model C - 04/11/17 11:49 pm

Not that my Matchless gets out much these days, but what I used in the four speed Sturmey Archer was Castrol LM grease ( now I think called Castrol All Purpose Grease) with the 50 weight engine oil I used ( Castrol CRB 50 ).
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/12/17 2:05 am

Originally Posted by Triless
what I used in the four speed Sturmey Archer
In 1928 Ariel used a Sturmey-Archer gearbox for one of their models and Burman for all the others. For the Sturmey-Archer the Owners' Guide recommends Speedwell Crimsangere while for the Burman it's to be Mobilubricant Extra Soft. So, different gearboxes, different greases.
Posted By: Triless

Re: Technical questions: 1928 Ariel Model C - 04/12/17 4:03 am

Yes, MM, Matchless recommended "Castrolease Light " for Sturmey Archer, and "Castrolease Medium " for Burman. I used what I could, and it seemed to work OK. When I finish mucking about with my Triumphs, I'll get stuck into the Matchless for some overdue attention, then I'll know how the SA stood up to my youthful depredations ! ( have'nt had the gearbox apart for years !)
It was recommended that " a small amount of oil ( half a teacup !? ) is of benefit with non fluid lubricated gearboxes ".
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/12/17 4:34 am

Originally Posted by Triless
then I'll know how the SA stood up to my youthful depredations ! ( have'nt had the gearbox apart for years !)
I don't know the usual mileage put on 90-year old bikes these days, but I want to avoid finding out after 2000 miles of day-after-day usage that I picked the wrong lubricant.

It's interesting that this thread started only yesterday and already it has more posts than any of the other 236 in the Ariel Forum
Posted By: Shane in Oz

Re: Technical questions: 1928 Ariel Model C - 04/12/17 6:30 am

Originally Posted by Magnetoman
It's interesting that this thread started only yesterday and already it has more posts than any of the other 236 in the Ariel Forum

It's an oil thread. They always do that.
Wait until you ask about fitting electronic ignition.
Posted By: Triless

Re: Technical questions: 1928 Ariel Model C - 04/12/17 8:41 am

MM, I'm not a world renown academic. I was only trying to help, using my experience as the criteria. I'll bet London to a brick, using modern grease, and the oil you use in your Ariel's engine, the bloody gearbox will be OK ! Got that ! Just going on what I know from previous posts, I think I've had a bit more time with a grease box than you ! OK ?
But I do know better , now, than to contribute my limited magneto experience !
Posted By: gavin eisler

Re: Technical questions: 1928 Ariel Model C - 04/12/17 9:53 am

Trying to help, I have a pitmans guide to Ariel motorcycles "The Book of the Ariel",, 1932 on. I have scanned some of the relevant lub pages. I hope this is of interest. Some of it may be useful.
[Linked Image]
[Linked Image]
[Linked Image]
Sadly it only covers the Burman box, not the earlier Sturmey archer.
Posted By: Triless

Re: Technical questions: 1928 Ariel Model C - 04/12/17 10:14 am

Yes, Gavin, this gells with my Haycrafts ( Pitman ) " The Book of the AJS ", " The Book of the Matchless " and my "AJS, FW Neill "(Pearson) all of which cover to a degree, both SA and Burman gearboxes.
What else did we mere neophytes have to go on ?
Posted By: Richard Kal

Re: Technical questions: 1928 Ariel Model C - 04/12/17 10:22 am

The rear sprocket on my 1927 Model A is 47T. From memory, your bike is the same.

Richard
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/12/17 4:00 pm

Originally Posted by Triless
I think I've had a bit more time with a grease box than you
I'm sorry if my response to your earlier post came across as dismissive. In no way did I intend it that way. I intended my response to be an explanation of why I might seem obsessed with a matter that appears it should be simple.

I found the following succinct explanation for why Burman used grease in the days before rotating shaft seals were up to speed, as well as why it can't be too thick. It was written by the late "Big Sid" Biberman of Vincent fame:

-----------
Burman Gearbox Oil: It can be a cause of rapid bushing, etc. wear if the grease is too thick and does not flow readily. The gears will tend to cut a track through it after which it does not flow into them continously. Also it will not enter tight bushing clearances. I suggest a small quantity of soft grease followed by sufficient 90 wt. gear oil to acheve the correct level. This way the soft grease gets carried into any leakage paths sealing them while the job of real lubrication is delt with by the gear oil. This works nicely in our Meteor and if not overfilled it rarely shows any seepage. Sid 6/18/07
----------

Originally Posted by gavin eisler
I have scanned some of the relevant lub pages. I hope this is of interest. Some of it may be useful.
Thanks very much for scanning and posting those pages. They bring the brands and grades of oils a step forward in modernity, helping the search for current replacements.

Meanwhile Morris Lubricants responded: "With regards to your enquiry for a Burman gearbox, our K400 EP Semi Fluid Grease would be our recommended alternative.". The relevant specs of that grease are an NLGI consistency rating of 00 and worked penetration value of 400-430. Thanks to a link from Shane in Oz these values make it a "semi-fluid" grease, one step softer than "very soft" grade 0 and only one step stiffer than the softest grade 000 which is also described as "semi-fluid."

Given that the specs and description matches well with the required properties it appears to be a good recommendation. But, that's the good news. The bad news is only Morris's range of 'classic oils' has a U.S. distributor. But, the good news is I emailed them anyway and they quickly responded that would be happy to add it to their next order from Morris at the end of May. I'm waiting to hear back how much 3 kg (~1 gal.) will cost me. That should be more than a lifetime supply even if the gearbox leaks like a sieve and I live to be 100.

Addendum: the price will be $51 + shipping, which is in line with the price/lb. of (thicker) lithium-based greases. I ordered it, so that makes one more line I can cross off my to-do list.

Originally Posted by Richard Kal
The rear sprocket on my 1927 Model A is 47T. From memory, your bike is the same.
Thank you very much. That's one more blank I can fill in on the 'general data' chart.
Posted By: robcurrie

Re: Technical questions: 1928 Ariel Model C - 04/15/17 2:56 am

Are you saying they might sponsor MM on the Canonball? :bigt

Rob C
Posted By: Hillbilly bike

Re: Technical questions: 1928 Ariel Model C - 04/24/17 4:18 pm

I was going to recommend John Deere Corn Head grease because it seems to function the same as the mentioned Morris grease....Corn Head grease is about 4 bucks for a 16 ounce grease gun cartridge...However, Corn Head grease is specified for slower moving gears and don't know exactly how this compares to the very expensive Morris lube...
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/24/17 4:39 pm

Originally Posted by Hillbilly bike
I was going to recommend John Deere Corn Head grease...
Maybe because of all the stories this past week on '420 day', when I read your post I wondered why people smoke corn husks, and why they need grease. But, thanks to the web I've now learned there is a farm implement called a 'corn head'. Not having seen a corn head in operation I visualize it slowly munching its way through a corn field so, as you said, the gears may be moving slower than those in an Ariel at 50 mph. But, I have Morris's recommended sem-liquid grease coming to me in a month so this particular problem is under control.

Speaking of things coming to me, the Ariel is in the air right now, due to land at LAX in six hours. Given what I the shipper told me are expected times to clear Customs and then be carried by truck to me the soonest I might have it is Friday, although early next week is more likely.

Trying to clear the deck to be ready for it I decided this weekend to rebuild my BB Gold Star's Magdyno. The bike runs great and a few months ago it successfully didn't strand a visiting Australian on a ~100-mile trip so there was a chance the previous owner had installed proper replacement capacitors. However, making my decision easier to fix something that didn't seem broken was that I found the inside of the Catalina's magneto, from the same guy, was a mess.

Anyway, when I opened the Magdyno I found the original Lucas condenser inside it . Its room temperature resistance was 7.6 megohm at 250 V so it still would (barely) exceed the Mil-Spec requirement at operating temperature (yes, there is a Mil-Spec for magneto condensers). But, the fact Lucas condensers started life at over 100 megohms shows it's well into its death spiral and that the Magdyno definitely was living on borrowed time.

The earth and HT brushes were fine so I treated it to new capacitors and grease, magnetized it, and ran it for 30 minutes at 2000 rpm. I had to quit before I tested how low in rpm it would go but will do that before I reinstall it.

While the bike is on the stand, and before the Ariel shows up, I'm going to completely wire it using LED bulbs and a NiMH battery pack. I bought a Podtronics regulator from John Healy a year ago that I originally had intended to use when I wired this bike, but since then I've been happy not to have any more lead acid batteries in my life. The 8-hour lighting provided by the NiMH packs I've been using is good enough for me and this is what I intend to use on the Ariel as well rather than swap its magneto for a Magdyno.
Posted By: kevin roberts

Re: Technical questions: 1928 Ariel Model C - 04/25/17 10:23 pm

combine with a corn head

[Linked Image]

with a grain head

[Linked Image]

the difference is in the width of the fingers separating the stalks. corn for large grain production is generally planted in fairly wide rows, and these fingers separate the stalks so the combine can thresh the ears and toss out the chopped straw. if the corn is to be cut green for silage, it's planted really close together and then is just chopped up and shot into a truck or a trailer alongside the tractor-- no combine.

small grain, like wheat, rye, or barley is just reeled into the sickle bar and threshed in-masse. no fingers on the small grain header.

my folks in oklahoma didn't use a combine. they would bring a stationary threshing machine out into the field and turn it with a belt drive off the side of the tractor, or pay somebody else to bring in a huge wheeled unit. later on one of the neighbors bought one, and they would hire him to do the work.
Posted By: Hillbilly bike

Re: Technical questions: 1928 Ariel Model C - 04/26/17 11:24 am

The Corn head grease video.....

How it works
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 04/26/17 4:19 pm

Originally Posted by kevin roberts
combine with a corn head...
Although I'm a city boy by inclination, spending time sitting in combines, tractors, balers, etc. in the farm implement display at the Iowa State Fair as a young boy made me want to be a farmer. Luckily, fate took me on a different path because farming is way too much work and economically way too uncertain.

Originally Posted by Hillbilly bike
The Corn head grease video.....
Thanks for posting that link. Who would have thought a video of grease flowing could be so fascinating? In light of this, maybe watching paint dry wouldn't be as bad as we've been lead to believe.

Ariel update: Anyone wanting to import a bike needs a printer and scanner for legal-size paper and software to create pdfs. They also need to make sure the local shipping agent (not just the overseas shipper) has the contact information as well as not to stray too far during the process to avoid delays and costly storage fees.

A few hours before the bike landed on Monday forms were emailed to print, sign, scan into a pdf, and email back allowing the customs house broker to act on my behalf. On Tuesday more forms arrived for me to certify the bike was older than 25 years and met all Federal emissions and safety regulations at the time it was made. Later I got another email from the broker saying they needed the full VIN, rather than the 'Z1234' I had printed on the forms, or else I wouldn't be able to register it with the DMV. I replied that the number stamped on the frame was the full "VIN" that had been used by Ariel 90 years ago. So far, nothing more since clarifying that issue so I don't yet know when it will be on a truck headed toward me. I'm having it delivered to a friend's shop that's closed Sun.-Mon. so if it doesn't get here by Saturday it will be Tuesday (or later) before I see it.

Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/04/17 10:21 pm

My friend dropped the Ariel off at a depot in Dublin on April 10 and it was at the shipper's warehouse in the UK, ~75 miles from Heathrow, the next day. Although its journey was off to a great start, at that point it hit molasses, taking 24 days to get to me despite having been shipped by "air."

Anyway, once it was at their warehouse it took the shipper (Oakbridge Logistics) 9 days to make the crate and then another 5 to get it on an airplane. Although the flight to LAX was quick, and it cleared Customs three days later, inexplicably it then took another 8 days to be delivered it to my house.

Actually, delivering it to my house was another problem since it should have gone to my friend's shop. Luckily, I didn't have any commitments on the afternoon it finally was to be delivered so I planned to be back home today to wait during the 1-5pm delivery window. The agent that Oakbridge had handling the shipping in the U.S. (Air Menzies International) was difficult to extract information from so by the time I discovered someone had screwed up the delivery address I decided it was safer not to try to fix the mistake (the trucking agency in town required any changes to be given to them by the shipping agent, not by me).

Although the delivery window was 1-5pm today, I got a call from the driver at 11:30am saying he needed to deliver it right away. So, I rushed home and arrived just as he did.

Unfortunately, I was taking photos so by the time I realized he didn't know what he was doing he had trapped the wheels of his pallet jack between the truck and the lift gate. The problem was the forks on the pallet jack were about 8" longer than the depth of the lift gate (i.e. making it impossible to use that pallet jack for this job) and despite that he lowered the gate a few inches. He couldn't lower it further because the forks started tilting the box off the gate, he couldn't raise it because the wheels now were in the way, and he couldn't safely drive it somewhere with proper loading equipment because the crate was hanging off the back of the truck. I took control at that point and with a hydraulic jack, load chain, and a couple of pieces of wood (none of which he was equipped with, nor did he even know how to use -- who doesn't know how to release the pressure in an hydraulic jack??) rescued my bike from the clutches of disaster.


All's well that ends well, and luckily I wasn't facing a time constraint, but it would have been faster to send the Ariel to the east coast by steamship (4 days in 1936) and then across the U.S. by locomotive (4 days in 1876). Seriously, some years ago I bought a bike from the factory in Italy, tracked it to the ship in Ligorno, two more stops in the Mediterranean to load and unload cargo, five ports down the East Coast, through the Panama Canal to Long Beach, through Customs, and by ground to me. That took 23 days, 1 day faster than the Ariel came by air.

Although it was boxed well, and eventually got to me in good condition (both very big positives, of course), if I were to do this again I would use a different company.


Attached picture 010delivery01.jpg
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Posted By: johnm

Re: Technical questions: 1928 Ariel Model C - 05/05/17 5:07 am

" if I were to do this again I would use a different company"

Probably a good plan.

Bike looks good although I understand you will completely rebuild it - It may have been assembled by the truck driver cousin ;-)

Posted By: kevin roberts

Re: Technical questions: 1928 Ariel Model C - 05/05/17 10:29 am

interesting hiw much faster stuff was so many years ago, although of course the volume was much less.

wasnt it about twenty years ago that the time it took to drive a car across london had slowed back down to the time it took holmes and watson to do the same in a hansom cab?

is the bike as nice as it looks?
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/05/17 6:29 pm

Originally Posted by kevin Roberts
is the bike as nice as it looks?
In a word, yes. Or, yes!

The bike was restored by someone who it appears was aiming for "original" so it looks very much like a nice, complete 1928 Model C. One difference is the front mudguard is the "Wide and large section, with extra valences" of the Model D (I can't see any differences in the catalog between the C and D rear mudguards). Also, when my taller friend bought it c2010 he had Chaterlea25 make a bracket to move the seat rearward and install different handlebars. I can already tell I like the shape of the handlebars, and the seating position feels fine as well (for the all of 2 min. I sat on it in the driveway), but I'll ride it for a while before I decide whether or not to make a bracket to move the seat forward to its original position.

The one item I spotted that might be a clue to the mechanical aspect of the previous restoration is that the rear sprocket is bolted to the hub and its teeth are as-new. It's not possible to be sure from the parts catalog but it appears the original hub/sprocket assembly was one piece. So, perhaps this assembly came from some later model, or it was machined to accept a replaceable sprocket. Either way, it's an encouraging sign that the mechanical pieces that can't be seen also might have been properly dealt with.

Looking back to a thread I started on the 'General Forum' on December 31, my description of the bike I hoped to find was:

Originally Posted by Magnetoman
...a "late" (i.e. closer to 1929 than to 1919) British bike with large capacity in fairly complete mechanical
but horrible cosmetic condition somewhere in N. America and for a "reasonable" (i.e. low) price because of the missing/decrepit sheet metal.... Since it would be fairly hopeless to restore the desired rolling basket case into anything resembling concours, the price should be low and hence the huge undertaking would be worthwhile to throw myself into over the next 20 months.
The first clause relates to the desired bike's mechanical capabilities while the rest is "merely" financial. On the first, essential, clause I did great. A 1928 Ariel is a large capacity British bike and its design is one of the most modern being produced in England at that time.

On the, um, "irrelevant" financial part I actually did OK as well. The purchase was between friends so I did not overpay. I did squander ~$2.5k to get it here but, even including that, thanks to Brexit and Frexit the dollar is strong and I suspect I could sell it in the U.S. today for about what I have in it so far. Besides, on the subject of squandering money, if I don't fly First Class, my heirs will.

Also, (knock wood) the fact that it is already complete and restored, rather than an incomplete basket case, should cut a large amount of time from that necessary to re-restore it. Even problematic Indian sheet metal isn't made for vintage bikes so making some random fuel tank fit reasonably well on a bare frame would take many hours. So, I've traded money to free up at least some time to do other things over the next 16 months leading up to the Cannonball. Like ride motorcycles. Again, if I don't fly First Class, my heirs will...
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/06/17 1:55 am

I had hoped to take it on its first short ride tomorrow, so this afternoon I checked it over. While I was able to grease the inlet rocker whatever residue is in the the exhaust rocker has solidified and wouldn't budge. The bike has those tapered grease fittings whose name I can't remember at the moment, which limits how much force can be applied to the grease. I now have 1/4-26 Zerk fittings on order. If that doesn't let me displace the residue the rockers will have to come apart. They would anyway as part of my rebuild but I was hoping everything was in good enough shape to put some miles on it before doing any actual work. Oh well...

The forks have grease fittings of a type I've not run across before (center item in the photograph). They're 3/16" OD and also threaded 1/4-26 and I'll substitute Zerk fittings for them as well.





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Posted By: kevin roberts

Re: Technical questions: 1928 Ariel Model C - 05/06/17 2:05 am

i used to work on antique cars that had a lot of screw-type grease cups:

[Linked Image]

might the reservoir that these provide be better for your purposes than just a zerk fitting? i'm thinking on terms of reliability on a long road race.

Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/06/17 3:31 am

Originally Posted by kevin roberts
screw-type grease cups ... might the reservoir that these provide be better for your purposes than just a zerk fitting?
Hmm, interesting idea. Thanks for suggesting it.

The forks have 5 grease points but they only need attention every 500 miles (i.e. every two days) so I think zerks should be fine there. For the rocker shafts the recommended interval is 300-400 miles so a shot every evening (~250 miles) should be as effective as full-time connection to a grease cup. Also, I'll have to remove the rocker cover at every gasoline stop (~100 miles) to oil the cups between the pushrods and rockers so it would be easy enough to give a shot of grease to each rocker shaft fitting at the same time.
Posted By: Hillbilly bike

Re: Technical questions: 1928 Ariel Model C - 05/06/17 11:07 am

Originally Posted by Magnetoman
I had hoped to take it on its first short ride tomorrow, so this afternoon I checked it over. While I was able to grease the inlet rocker whatever residue is in the the exhaust rocker has solidified and wouldn't budge. The bike has those tapered grease fittings whose name I can't remember at the moment, which limits how much force can be applied to the grease. I now have 1/4-26 Zerk fittings on order. If that doesn't let me displace the residue the rockers will have to come apart. They would anyway as part of my rebuild but I was hoping everything was in good enough shape to put some miles on it before doing any actual work. Oh well...






I have had the same problem on many vintage vehicles, old tractors etc...Heat applied to the fitting area carefully with a torch and it'll warm up the shaft or bushing to soften the oil grease.. Hold the heat to about 250-300 F for a few minutes... Then use use a grease gun to try and force in new grease. Works best with Zerks...
The Wright radial aircraft engine used for Lindbergh's solo flight across the Atlantic in the 1920's has grease fittings on the rocker shafts like most engines of it's day...Spring loaded "automatic" grease cups were used for the long trip...Some vintage cars had a series of small tubes leading to the fitting from a central grease pump that could be operated while running on the road..
That's a sharp looking machine.....
Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 05/06/17 12:50 pm

Hi,

Originally Posted by Magnetoman
[Linked Image]

I was taking photos so by the time I realized he didn't know what he was doing

Don't be too hard on him, that's a rookie mistake he won't make again - that could've been a picture of me whistle years ago. Looks like some US trucking company managers are just as big bastards as some British ones - as long as fork-lifts can move a pallet in the depots, they'll take the money and pay the poor sob in the picture a pittance to take the flak from the addressee. mad

The picture two minutes earlier would've told me it was never going to come off in the crate, quicker would've been to climb up in the truck with pry-bar, open the case, unstrap the bike and wheel it on to the tail-lift - I still remember having to do that with a crated ride-on lawnmower! cool

Originally Posted by Magnetoman
forks on the pallet jack were about 8" longer than the depth of the lift gate (i.e. making it impossible to use that pallet jack for this job)

Nope. A more-experienced truck driver would've told the fork-lift driver to load the pallet jack before the crate; then, if you're lucky, the wheels on the tines of the pallet jack can be pushed off the rear edge of tail-lift without everything falling off the tail-lift; when the tail-lift's dropped to the ground, crate and pallet jack can be wheeled off. cool

Regards,
Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 05/06/17 12:51 pm

Btw, bike. :bigt

From another BVC (BritBike Vicarious Cannonballer grin ).
Posted By: Bruce Martin

Re: Technical questions: 1928 Ariel Model C - 05/06/17 12:55 pm

A bit late with this but I use Lubriplate MAG-00 semi-fluid grease in my 1937 Ariel Red Hunter 500's Burman BA gearbox. I did use steam oil for a short time. No problems so far.

Bruce
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/06/17 6:08 pm

Originally Posted by Hillbilly bike
Heat applied to the fitting area carefully with a ...Works best with Zerks...
Good suggestion, thanks. I have a pump for those old British fittings but even holding it in place and whacking the end with a rubber mallet doesn't apply all that much pressure to the grease. I decided to wait until the zercs show up so a modern grease gun can apply some serious pressure to get things moving. If that doesn't work I'll add some of your heat to the mix and only then give up and start disassembling the rocker mechanism.

Originally Posted by Hillbilly bike
The Wright radial aircraft engine used for Lindbergh's solo flight across the Atlantic in the 1920's has grease fittings on the rocker shafts like most engines of it's day...
On the subject of proper grease for engines like Lindbergh's and mine, I came across the following a few days ago:

http://www.jewellamberoil.com/

It sounds ideal for my use, although I'd feel better if it were supplied by a known lubricants company.

Originally Posted by Hillbilly bike
That's a sharp looking machine.....
Thanks. Looking good wasn't part of my search criteria but I'm very pleased with its appearance:

Removing the pillion seat improved its looks by 20%, and if I move the seat forward to its original position that should be good for another 10%. I certainly won't be embarrassed to be seen riding it.

Originally Posted by Stuart
quicker would've been to climb up in the truck with pry-bar, open the case, unstrap the bike and wheel it on to the tail-lift
It's not clear from the photo, but the ends of the crate overlapped the sides, which means the screws had to be removed from the ends before the sides could come off. Because there was no clearance between the walls of the truck removing those screws in place would have been impossible. Brute force to break the wood to gain access would have been the only choice, but what the photo also doesn't show is that 90 min. after it was taken the temperature officially hit 100 oF for the first time this year. All the effort that would have been needed to pry open the box would have been done while working in an oven with no air circulation.

Originally Posted by Stuart
Btw, bike. :bigt
Thanks!

Originally Posted by Bruce Martin
I use Lubriplate MAG-00 semi-fluid grease in my 1937 Ariel Red Hunter 500's Burman BA gearbox.
Thanks. I took a quick look at its specs and it seems fine for the purpose. But a jug of the Morris semi-fluid grease should be showing up in a few weeks so I should be OK for the gearbox.


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Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/08/17 1:28 am

Nothing is easy. I'm sure I'll repeat that sentiment many times in the months to come. It was remarkably difficult to measure the dimension of the timing chain, and I probably should have taken it off the bike to do, but I hate disturbing a master link, especially when I don't have a spare one handy. Anyway, I'll want to pack a spare timing chain for the ride and the one on the bike has dimensions:

pitch 1/2"
roller diameter 0.306"
roller width 1/8"
pin diameter ~0.140" (estimated from the measured swaged end).

If not for the roller width this would be #40 chain (which has either 3/16" or 1/4" width depending on the source). But, it's too narrow to be #40. If anyone knows where I can buy chain with these dimensions I would really appreciate hearing from you.

Update: Cancel my question. I already had searched for quite a while, but a minute after posting this question I found it is "non-standard" #43. I now have 10 ft. of it on order along with a few extra master links.
Posted By: Alan_nc

Re: Technical questions: 1928 Ariel Model C - 05/08/17 8:22 am

And that was probably the cheapest part you will buy for this "journey"
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/08/17 4:34 pm

Originally Posted by Alan_nc
And that was probably the cheapest part you will buy for this "journey"
There's the cost in dollars, and then there's the cost in time. In the end it probably "cost" me an hour to buy that chain (plus the time it will take to cut 35 links from the 10 ft. length once it arrives). And that's for a backup part that, knock wood, I won't even need. Even if everything turns out to be as straightforward as the chain, this Ariel is going to cost a lot of hours before it will be ready for the Cannonball.
Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 05/08/17 5:53 pm

Hi,

Originally Posted by Magnetoman
Nothing is easy.
I already had searched for quite a while,

Ahem ... <koff> ... without at all wishing to appear a smart-arse, I converted your dimensions into standard roller-chain code = 410 (1/2" pitch is 4 x 1/8", roller width is 1 x 1/8"), typed "410 chain" into Google and http://chains.alliedlocke.com/item/precision-roller-chains/non-standard-series-chains/410-43-65-nss was third from the top of the list ... it appears to be a box-stock modern pushbike chain so, if Google and eBay are to be believed, the First World is awash with any length and Teflon-coated farkle you could imagine ...

Originally Posted by Magnetoman
Even if everything turns out to be as straightforward as the chain, this Ariel is going to cost a lot of hours before it will be ready for the Cannonball.

Don't struggle with searches for so long? wink

Regards,
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/08/17 8:06 pm

Originally Posted by Stuart
I converted your dimensions into standard roller-chain code ... it appears to be a box-stock modern pushbike chain
Box-stock, but non-standard chain. The heading on the link you have says:

Item # 410(43)(65), Non-Standard Series Chains

Indeed, I found it the same way you did. But, only after not finding it by googling lists of standard chain. If nothing else, this shows that, as is often the case, once the answer to a problem is known the route to getting to that answer is obvious.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/10/17 12:25 am

Today I hauled the Ariel in for the required physical inspection of the numbers. Tomorrow, barring any unexpected glitches, I'll pick up the title, registration, and license plate.

After strapping the front down in the pickup I wiggled the back to make sure the bike was secure. The forks didn't move but the rest of the bike did. The steering bearings weren't loose enough to 'click' but they definitely were loose. Additional support for my decision to completely rebuild the bike.
Posted By: kevin roberts

Re: Technical questions: 1928 Ariel Model C - 05/10/17 12:32 am

that is a beautiful machine, no doubt about it.

did you manage to scrounge any history of it's past 90 or so years? there have been almost a century of owners, and i always wonder what the stories were.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/10/17 2:31 am

Originally Posted by kevin roberts
that is a beautiful machine,
did you manage to scrounge any history of it's past 90 or so years?
It was despatched from the factory 13 December 1927 to C.J. Rouse Motorcycles, Kettering, England, and it found its way into my friend's garage in Dublin ~83 years later. Between those dates, ¿quien sabe? Actually, I also know the name of the guy who sold it to my friend but I don't know its history with him, or before him.

Someone easily could overlook a Black Ariel amongst brighter, more colorful bikes (as I did for five years in my friend's garage), but once noticed I think it's quite fetching.

Posted By: gREgg-K

Re: Technical questions: 1928 Ariel Model C - 05/10/17 3:43 pm

Originally Posted by Magnetoman
Originally Posted by kevin roberts
that is a beautiful machine,<SNIP>
<SNIP> but once noticed I think it's quite fetching.

Indeed, and I for one am glad that you fetched it!

.. Gregg
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/10/17 5:48 pm

Originally Posted by gREgg-K
Originally Posted by Magnetoman
I think it's quite fetching.
I for one am glad that you fetched it!

And I'm glad it didn't fetch too high of a price.

Update: The Ariel now has a title and registration. I splurged on a classic vehicle plate ($25 one-time fee + $10/year extra), because I figured a bike that has survived 90 years has earned it. Getting it licensed so easily was actually a big relief because I was afraid I'd have to spend endless hours at the DMV since the bike isn't just from out of State, it's from out of Country.

p.s. the tracking number shows the zerc fittings are due to be delivered later today. If that works to clear (and grease) the exhaust rocker I'll try to fire it up this weekend and take it on a tour of the neighborhood.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/15/17 5:32 am

The BS zerc fittings arrived on Thursday, I got the appropriate grease for the rockers on Friday, and yesterday the grease gun arrived. I modified the gun and it nicely solved the issue of getting grease to the inlet rocker arm. I greased all the other points so at that point it only needed fuel.

This morning I took the Ariel and the DocZ rollers out of the garage, but when I added fuel the petcock leaked like the Titanic. It's of a slide type with no obvious way to rebuild it to stop the fuel from leaking out the sides. I have a box full of petcocks, but none have the necessary prehistoric thread to fit so I machined an adapter of sorts. I threaded a piece of 3/4" OD brass to go into the tank and with an OD on the other end to allow a piece of Tygon to connect the tank to the compression fitting on the pipe leading to the carburetor. A small Vise-grip on the Tygon served as the petcock.

Unfortunately, now that fuel was getting into the carburetor it started getting out of the carburetor. I tried swapping an O-ring for the leaking gasket at the base of the Type 6 Amal but without success. I then found a fiber gasket of almost the right size in my drawer of Amal gaskets. However, its OD was maybe 1/32" or 1/64" too large to fit in the carburetor so I had to grind it to size. Unfortunately, that didn't stop the leak, either. Since the gasoline was dripping directly onto the magneto I decided it best not to put the Ariel on the rollers.

At that point I drained the gasoline and put the bike back on the lift to await a gasket kit for the Type 6 Amal. But, before calling it a day I machined another brass adapter to accept a nice brass petcock with a tapered plug. After lapping the valve I assembled it with EZTurn petcock lubricant so all I need now is that carburetor rebuild kit. At least, as far as I know...
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 05/15/17 10:49 am

The old cork pet usually responds to a hot soak in water, The fibre washer on my old carb seems to need a regular nip up to stop it leaking , I dont think they are made of the right stuff to resist the fuel and soften.The tap thread is most likely to be bsp and its all still availiable if you want it.. Gas is not good for old mags , You can probably fix the mag tho-----------!!.
Posted By: gREgg-K

Re: Technical questions: 1928 Ariel Model C - 05/15/17 1:51 pm

MM,

Regarding fuel leakage from the push-pull tap, I'd agree with norton bob ... the cylindrical cork "seal" in the sliding member has probably dried out and shrunk. If it hasn't split, as Bob says, sometimes they can swell up again if soaked in hot water ... and even some times simply after soaking in gas. Last one I had was fine after the petcock spent some quality time in my (heated) ultrasonic cleaner.

If your carb is leaking profusely from the threads at the base of the carb body, I wonder if the fuel level is too high in the float chamber? You may already have checked this but the float may not be clipped into the correct groove in the needle valve/rod, or the actual valve face may need lapping to help it seal better. The float could be stuck, or may even be leaking ... but in any case no point in risking your bike becoming a Molotov cocktail during your first ride!

.. Gregg

Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/15/17 6:40 pm

Originally Posted by norton bob
The old cork pet usually responds to a hot soak in water, The fibre washer on my old carb seems to need a regular nip up to stop it leaking , I dont think they are made of the right stuff to resist the fuel and soften.The tap thread is most likely to be bsp and its all still availiable if you want it.
Originally Posted by gREgg-K
If your carb is leaking profusely from the threads at the base of the carb body, I wonder if the fuel level is too high in the float chamber? You may already have checked this but the float may not be clipped into the correct groove in the needle valve/rod,
Guys, thanks for the responses. Actually, the petcock isn't one of the cylindrical Ewarts types with dried out cork, it has a flat guillotine slide with no remnants of whatever in the past sealed it, so the slide rattles in the housing leaving as much area, if not more, for fuel to leak out onto the bike as it does to pass through to the carburetor.

The hole in the bottom of the fuel tank is 7/16"-20 and no doubt has a Whitworth form, but that's close enough to UNF that the thread formed by a UNF die is a good fit. There is no 20 tpi BSPP thread so whatever the thread is, it's something other than BSPP. A fiber gasket takes care of sealing it to the tank, but I put EZTurn petcock grease on the threads as well in a belt-and-braces approach.

The more difficult problem I had yesterday is the thread on the end of the brass petcock I used is 3/8-28 which makes it a (nominal) 1/8" BSPP with major diameter 0.383", i.e. 0.008" larger than 3/8". Lacking the appropriate tap (which is now on order for the future), but having a lathe, I threaded the brass myself using the petcock as a go/nogo gauge. It happens that I have carbide inserts with the proper Whitworth form but I simply used the 60o threading insert already on the boring bar. I then put the adapter in the mill and made six flats to use to tighten it on the tank. Miraculously, although of arbitrary size, these flats are a perfect fit to my Crescent wrench (although, I've only tested it with one Crescent wrench so far...).

The carburetor might have been fine as received, but my "mistake" was taking it apart to check everything. When I did so I saw that the large gasket that seals the mixing chamber was degraded but I reassembled it anyway with my fingers crossed that there was enough surface area that it would seal despite that. As we know, crossing fingers seldom works when rebuilding bikes and this was no exception. But, I wanted to hear it run, and would be properly rebuilding the carburetor in the future, so I tried it anyway.

The float is clipped on the sole groove in the rod but I haven't yet checked if the valve seals properly or if the level is correct. But, even if the level were too high, if the gasket in question were working properly fuel wouldn't be getting past it to come out the threads at the base of the mixing chamber. But, no matter, next on the to-do list is to properly rebuild the carburetor, make sure the float doesn't leak, check the fuel level, etc. I'll have it off the bike, apart, and ready for the gasket kit when it arrives.


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Posted By: gREgg-K

Re: Technical questions: 1928 Ariel Model C - 05/15/17 7:36 pm

Originally Posted by Magnetoman
<SNIP> Actually, the petcock isn't one of the cylindrical Ewarts types with dried out cork, it has a flat guillotine slide with no remnants of whatever in the past sealed it, so the slide rattles in the housing leaving as much area, if not more, for fuel to leak out onto the bike as it does to pass through to the carburetor.<SNIP>


I should have known, MM ... I had a small bag of NOS corks for that type of tap, and I have an uneasy feeling that I pitched them a few years ago.

Anyhow, those seals should be fairly easy to make by a man of your abilities. The seals are small disks of cork, about 3/32" thick, one above the guillotine and one below. They are trapped in place by a shallow spigot that sticks out of the valve body.

I'll see if by any chance I have any left here.

.. Gregg
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/15/17 9:09 pm

Originally Posted by gREgg-K
I'll see if by any chance I have any left here.
Gregg, thank you very much for offering but I'm going to stick with the all-metal petcock. Besides, cork shouldn't be wasted trying to slow the leaks from gasoline petcocks when a much better use is for sealing wine bottles.
Posted By: gREgg-K

Re: Technical questions: 1928 Ariel Model C - 05/15/17 11:19 pm

You're welcome in any case, MM.

I have to agree with you, that on a run like the Cannonball, the all-metal petcock is going to be a better bet ... not to mention, safer!

.. Gregg
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/16/17 12:10 am

Originally Posted by gREgg-K
the all-metal petcock is going to be a better bet ... not to mention, safer!
A good thing to come from this is the Ariel will be treated to a drip shield. Had gasoline streaming down on the magneto not made the potential danger abundantly clear I might not have thought to add such a shield until the bike went up in flames.


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Posted By: robcurrie

Re: Technical questions: 1928 Ariel Model C - 05/16/17 3:12 am

I would recommend that for the Canonball, you fit a fire extinguisher in a handy position. (It might already be specified in the regulations).

Rob C
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/16/17 3:27 am

Originally Posted by robcurrie
fit a fire extinguisher in a handy position.
I have four fire extinguishers spaced around my garage so it's something I take fairly seriously. Even before the weekend's gasoline spill a fire extinguisher was on my list of items to buy and mount in an easily accessible location on the Ariel. One bike burned to the ground on the last Cannonball.
Posted By: gREgg-K

Re: Technical questions: 1928 Ariel Model C - 05/16/17 10:23 am

Originally Posted by Magnetoman
<SNIP>One bike burned to the ground on the last Cannonball.

True, that bike made a real ash of itself.

..Gregg
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/16/17 5:03 pm

Originally Posted by gREgg-K
True, that bike made a real ash of itself.
A fire extinguisher wouldn't have helped by the time it was to this point, but probably would have a few moments earlier had he had one strapped to the back of his bike where it was quickly accessible:
[Linked Image]
I'd never thought of carrying a fire extinguisher on a bike before, but this incident caught my attention given the age of all the machines. I note, though, that it happened on the first day, and earlier the owner had been quoted as saying the bike was a "work in progress," so if nothing else it points to the importance of proper preparation before showing up for the start.
Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 05/17/17 12:50 pm

Hi,

Missed a few episodes owing to it being swmbo's birthday (if it means anything ... to Applecross over the Pass Of The Cattle for lunch. smile ).

Originally Posted by Magnetoman
The hole in the bottom of the fuel tank is 7/16"-20 and no doubt has a Whitworth form, but that's close enough to UNF that the thread formed by a UNF die is a good fit.

Surprised no-one else mentioned it but 7/16"-20 and "the thread formed by a UNF die is a good fit" almost certainly means it's Cycle. smile

Originally Posted by Magnetoman
the petcock isn't one of the cylindrical Ewarts types
has a flat guillotine slide

Not sure what a "cylindrical Ewarts type" is but, looking at your earlier pictures, 'UK & General Export' unit 350 and 500 Triumphs use what looks/sounds like a similar combined main-'n'-reserve tap - 82-1717:-

[Linked Image]

... one plunger is main, the other reserve, I have at least one with rubber rather than cork seals; if suitable, might be available from someone like Rabers?

Hth.

Regards,
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/17/17 4:23 pm

Originally Posted by Stuart
Surprised no-one else mentioned it but 7/16"-20 and "the thread formed by a UNF die is a good fit" almost certainly means it's Cycle.
Although anything is possible on a 90-year old bike, including that the thread in the tank was retapped, I don't have a CEI die that large. I would have thought Ariel would have used a BSPP originally since the application is for a pipe.
Originally Posted by Stuart
Not sure what a "cylindrical Ewarts type" is...
It's the petcock at the left below.

Originally Posted by Stuart
....but, looking at your earlier pictures, 'UK & General Export' unit 350 and 500 Triumphs use what looks/sounds like a similar combined main-'n'-reserve tap
The photo in the middle below is the guillotine-type petcock that was on it:

Note that once the sealing material above and below the slide has disappeared there is plenty of room for fuel to exit onto the ground from around the slide, which is what mine was doing.
Originally Posted by Stuart
one plunger is main, the other reserve,
An additional constraint this past weekend is I wanted to use the coiled copper pipe that runs between the petcock and the carburetor. Although the pipe looks quite the vintage part it is stiff, and if work-hardening hasn't already reached the point of brittleness I wouldn't risk it on the upcoming run. However, it was faster not to have to find the necessary compression fittings, solder them to short pipes, and replace the coiled Cu with rubber hose along with everything else I was doing to try to get the bike to the point where I could start it. As a result, the petcock + adapter can't be too long or it wouldn't fit with the existing pipe. Those "modern" petcocks of the type in your post and in my box require adapters to mate with the tank and overall are too long.


Aside: I hate how much time Photobucket forces me to waste in order to insert images in my BritBike posts. Uploading the above three photographs reminded me why I haven't started a restoration thread here on this bike. What's needed is the ability to copy/paste images directly into a post since software can easily and automatically resize photographs in a directory to any size needed prior to the copy/paste. I realize the current Britbike software might make such a simple 21st-Century solution impossible, and in any case it would require Morgan to arrange for a huge amount of storage space on his server, but I've about reached my limit of patience for posting photographs.


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Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 05/17/17 5:51 pm

Hi,

Originally Posted by Magnetoman
I hate how much time Photobucket forces me to waste in order to insert images in my BritBike posts. Uploading the above three photographs reminded me why I haven't started a restoration thread here on this bike.

Thanks for the clarification, and apologies that it took so much time when I just linked a picture already on someone's web server ... The upside of posting pictures is not having to write the equivalent "thousand words"? smile

Regards,
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/17/17 6:12 pm

Originally Posted by Stuart
The upside of posting pictures is not having to write the equivalent "thousand words"
I couldn't agree more. That's why it's so frustrating to have to waste so much time to upload pictures here. The word 'waste' is appropriate because in 2017 software exists to make the process so much quicker and easier. Unfortunately, the underlying "engine" on which BritBike is built dates from twenty years ago, when digital cameras only were in the hands of relatively few people, so whether or not the code is flexible enough to be suitably modified remains to be seen. I certainly hope so, and I know Morgan does as well.


Posted By: Tridentman

Re: Technical questions: 1928 Ariel Model C - 05/18/17 11:39 am

I thought that "Premium Membership" of Britbike meant that you can upload photographs directly?
That was one of my motivations for changing to Premium Membership--although I have not had the need to try the direct upload yet.
HTH
Posted By: RPM

Re: Technical questions: 1928 Ariel Model C - 05/18/17 2:02 pm

MM, Have you thought about an auxiliary fuel tank for extra range? We had one on the Norton and plan to install one on all the Cannonball Nortons in 2018. A range of 150 to 175 miles is what we plan to have.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/18/17 4:18 pm

Originally Posted by Tridentman
I thought that "Premium Membership" of Britbike meant that you can upload photographs directly?
It's not as simple as it might seem. The ability to insert "image tags" certainly streamlines some things but is a band-aid for the overall problem, especially when writing something longer than a quick answer to a question,and that requires more than an image or two. Such as a restoration thread. Such threads have to be composed and maintained off-line and cut/copied into BritBike. Also, the loss of a significant number of posts a couple of years ago further highlights the importance of keeping one's own "backup" of such threads including photographs, since they also might be lost if there's another Britbike apocalypse. While "image tags" can speed things up for simple posts, they aren't a solution for more complicated ones.

Originally Posted by RPM
MM, Have you thought about an auxiliary fuel tank for extra range? We had one on the Norton and plan to install one on all the Cannonball Nortons in 2018. A range of 150 to 175 miles is what we plan to have.
Thanks for mentioning this because it's certainly important. At this point I haven't given much thought to range other than doing the following calculations that show the stock tank should put me in the right ballpark. My tank holds 2.4 U.S. gallons and Titch Allen's 1970s review of a 1928 Model C quotes 60 to 70 miles per Imperial gallon. This would mean a range of 120-140 miles. A 1928 test in The Motor Cycle said that at 35 mph on a main road they got 104 miles/Imp. gallon (87 miles/U.S. gal.). This would mean a range of 209 miles.

On average we will cover 4000 miles/15 days = 267 miles/day, which means ~140 each morning and afternoon. Taking Allen's value, as long as we don't take any road where gasoline stations are more than ~100 miles apart, and if I stop for fuel (and to take breaks from the rigid frame) mid-morning and mid-afternoon, the stock tank would be fine. However, I certainly hope to have the bike rebuilt soon enough to have plenty of miles riding it before the start, and to know what fuel consumption it gives the way I ride it. Once I have that data I'll know whether or not I'll have to carry extra fuel.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/19/17 10:29 pm

Over the past few days I completely disassembled the carburetor, cleaned and inspected every passage, and lapped the brass seat in the float bowl. When I tested it earlier today using old fiber washers none of them leaked, the fuel level was right where Chaterlea25 told me it should be, and the level didn't rise with time, i.e. the lapping was good. I also had modified a BSA A10 drip tray with an extension under the float bowl so any leaking fuel would be directed toward the ground rather than toward the magneto's HT connector.

Even though the new carb rebuild kit hasn't arrived yet I couldn't stop myself from installing the carburetor and dragging the bike out of the garage to try to start it. I used my DocZ rollers but it started remarkably easily, oil immediately started dripping in the sight glass as it should, and so I put it in 1st and made three laps of the driveway. Although the laps were slow, they were fast enough to tell me the front brake needs proper linings.

The only comment I could hear my wife make during one of my brief stops was "You're going to ride across the U.S. on that?" Indeed I am, indeed I am.

It left a fair bit of oil on the driveway wherever I stopped so I put it back on the lift to figure out why that's the case before I take it out on the road. Since the patches are blackish it's old oil not the new stuff I put in the tank so it could be a simple as the sump needs to be drained. Although it's called "total loss" the engine actually needs to be drained of the accumulation every 1000 miles.

I'm as happy with this Ariel as I was when I got my first motorcycle when I was 15, i.e. very happy.


p.s. I drained 80 cc of black oil from the sump so that, plus an open-ended pipe under the engine, could explain the splots on the driveway. Fun as it would be to head off through the neighborhood, I'm taking a better-safe-than-sorry approach as I acquaint myself with its pre-historic oiling system since replacement parts wouldn't be easy to find.

p.p.s. I've now been told by another Black Ariel owner that whenever the crankcase is drained that 50 cc needs to be added back. It seems that with these Ariels wet sumping isn't bad, it's important. Clearly, I'll be on a learning curve with its idiosyncrasies for a while.


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Posted By: robcurrie

Re: Technical questions: 1928 Ariel Model C - 05/20/17 12:08 am

I know the feeling. I got my first motorcycle when I was 11. It was a moped that was standing in a garden under a tree for years and I walked past it every day going to school. I begged the owners mother to ask her son if he would part with it and after about a year she stopped me one day and said I could take it. The tires had rotted away and the engine was rusted solid, but I eventually got it running, although I could never afford tires.

Rob C
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/22/17 5:18 pm

Not surprisingly, I suppose, information on oiling characteristics of this 90-year old Ariel has been incomplete and inconsistent, leaving me pretty much on my own to figure out what's normal and what's not.

Yesterday I ran a length of Tygon from the timing case breather tube to a small catch bottle zip tied to the frame so I will be able to see how much oil comes from that source after having drained the crankcase. One possibility that was suggested was that the 80 ml of old oil I drained from the crankcase might have been enough to reach the main bearings, leaking from there into the semi-sealed primary and onto the ground. If that was the source, a few laps of the driveway should result in smaller puddles than on my initial run. If it passes that test I'll make a ~2 mile run in the neighborhood. In steady state the sight glass should show 10-20 drops/minute so with ~40 drops/ml that means in steady state no more than ~5 ml should be collected in a ~10 min. run.

I also wired the bike for a NiMH-powered LED stoplight so it won't take long to attach the age-appropriate taillight/license assembly when it arrives any day now. I have other such assemblies I could use (from the '50s and '60s) but don't want to drill unnecessary holes. With a stop light and license plate, the world opens up.

The final thing I did on it this weekend was to replace the Cu fuel line with clear Tygon along with a fuel filter.
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 05/24/17 6:51 pm

Never ran a total loss bike,but a thought just struck me, back in the day 2 stroke oil did not exist, would it make sense to run it on 2 stroke, it could burn up the oil with little ash, a dash in the fuel and the rest from the pump.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/24/17 9:38 pm

Originally Posted by norton bob
run it on 2 stroke, it could burn up the oil with little ash, a dash in the fuel and the rest from the pump.
Thanks. Low ash oil is a good suggestion and that's what I already have in it and I plan to use on the rally. Although I know people use oil in their fuel, sometimes just to get the smell of Castrol R, its presence lowers the octane. Whether or not this would be an issue with the Ariel depends on its as-yet-unknown compression ratio.
Posted By: robcurrie

Re: Technical questions: 1928 Ariel Model C - 05/25/17 12:56 am

The Mercedes Formula One racing team are suspected of burning engine oil to get more power from their engine. OK, they are running turbochargers (so they were probably injecting oil into the exhaust before the turbo) and rules restrict fuel consumption, but this year there is a new rule restricting oil consumption!

Rob C
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/25/17 2:18 am

Originally Posted by robcurrie
The Mercedes Formula One racing team are suspected of burning engine oil to get more power from their engine. ... this year there is a new rule restricting oil consumption!
Damn, that new rule effectively eliminates my Ariel from competing in Formula One. Oh well, I guess I'll have to be satisfied with the Cannonball.
Posted By: JubeePrince

Re: Technical questions: 1928 Ariel Model C - 05/25/17 10:53 am

Originally Posted by Magnetoman
There's the cost in dollars, and then there's the cost in time. ....this Ariel is going to cost a lot of hours before it will be ready for the Cannonball.


MMan -

Not to mention the hours you're spending here, asking/answering questions and documenting your endeavour. Your willingness to share information and answer questions make you a mensch, IMO. Just about everything I've learned about these old bikes came from sites like this and people like you. Without such resources, I would have probably ruined my bike a long time ago, or at the very least made some really poor decisions that I would have later regretted.

Looking forward to following your journey to a hopefully happy conclusion, whatever your definition of 'happy' may be!

Cheers,

Steve
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/26/17 5:24 am

Originally Posted by JubeePrince
Not to mention the hours you're spending here, asking/answering questions a...
Well, there is that. But, although I wouldn't know how to quantify the balance, in return for spending those hours I've also gained considerably from others on BritBike. Thanks very much for your nice comments.

Today's progress on the Ariel was limited to sending a large pile of cash to Ireland. My friend obviously wasn't too concerned about me being good for the money because it took a few weeks of nagging him before he finally got around to sending his banking information. The amount exceeded my bank's limit for on-line transfers but it only took 5 minutes at the local branch to take care of it. Although the bike was mine when it arrived it didn't feel quite right until I got this final "detail" taken care of.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/27/17 4:59 pm

On the subject of gearing I read that several sets of gears had been available at the time. My gearbox is stamped QL but I didn't know what that meant until this morning. I think I've found the information, although I don't understand the logic of the terminology that Burman used.

The last page of a 1929 Burman spares catalogue gives the internal ratios of the "High Standard," "Low Standard," and "T.T.A." gearing in their 'Q' gearboxes. Presumably, the first is stamped QH and the second is the one I have, QL.

The ratio of the 1st gear ratio to the 3rd gear for each of these is:
High Standard: 2.02 (stamped QH?)
Low standard: 2.79 (stamped QL?)
T.T.A.: 1.60

So, this would make the QH the close ratio (the T.T.A. the super-close ratio) and the QL the wide ratio. Although, I don't see the logic in using the words "high" and "low."

Calculations show that in all three cases Burman picked the three ratios to be evenly spaced, i.e. with the ratio for 2nd midway between that between 1st and 3rd. But, especially with the "Low Standard" (i.e. mine) they must feel like especially large jumps.

For comparison, the "Std" gearbox on pre-unit BSAs has an overall ratio difference of 2.58 between its low and high gears, i.e. roughly the same spread as the 2.79 on my Ariel. So, take that BSA gearbox and make it into a 3-speed with the intermediate ratio falling between the current 2nd and 3rd. The shifts would be from 1st to 2.5th to 4th.

As an example of what this means, when shifting the Ariel into 3rd at 4000 rpm the engine will drop all the way to 2400 rpm. Especially when we hit the Rockies I can imagine plenty of times when 3rd will be too high and 2nd too low.

When riding my 4-speed bikes I've often wished for one more gear. With the Ariel my wish was granted, the wrong way...

Posted By: Alan_nc

Re: Technical questions: 1928 Ariel Model C - 05/27/17 5:50 pm

Is it legal in the event to change sprockets the night before you are riding into mountains? I know this doesn't change the ratio but at least you might have a gear low enough to make it up some of the hills.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/27/17 6:45 pm

Originally Posted by Alan_nc
Is it legal in the event to change sprockets the night before you are riding into mountains?
The short answer is, yes. The long answer is:

It's going to take some thought as to what is the best compromise gearing to use (assuming the necessary engine sprocket is available). As a reminder, the Cannonball's instructions say the motorcycles "need to maintain at least 43-50 mph on straight, flat roads."

The Owners' Guide has a gearing chart showing the rpm at various speeds and gear ratios. The highest rpm shown is 5630 although most entries top out at 5400-5500.

As an example, if based on the above I take 5500 as the true redline for this engine and gear it so it's 4500 rpm at 65 mph to keep well below redline even on a few short segments on Interstates, that means at 50 mph in top gear the engine will be at 3500 rpm. Although that sounds good, if the engine doesn't have the h.p. at that rpm to hold 50 mph climbing a long incline, or to regain that speed if balked by a motorhome, dropping down into 2nd would have the engine above redline at 5600 rpm. Or, the same 3500 rpm could be maintained in 2nd gear if the speed were dropped to 31 mph.

While it seems unlikely (I hope) that the organizers will take us over the Continental Divide on an Interstate where being able to hold at least 50 mph would be important, the above calculation shows why thought has to go into the overall gearing.

Lucky for me, the bike has a bolt-on rear sprocket so changing it will be no more difficult than changing a tire (not that changing a tire is easy or fun...). It has the stock number of 47 teeth and is ~9" in dia. While it couldn't be replaced with a smaller sprocket, one as large as ~10.5"-dia. could fit without causing the chain to interfere with anything, which would have 55 teeth. In the above example at 50 mph on that road in the Rockies the engine would be at 4100 rpm where it would have more hp.

Anyway, I'll certainly be giving more thought to gearing issues as time goes on. Ten miles from my house is the start of a mountain road that climbs to 8000 ft. in 27 miles so I'll be making good use of it to test both gearing and jetting in the months ahead.



Posted By: RPM

Re: Technical questions: 1928 Ariel Model C - 05/29/17 4:22 pm

We changed the motor sprocket on the 1915 Norton. We had 14 to 18 tooth sprockets. Ran the 17 the first day. We changed to the 15 on the second day as the were riding through West Virginia. Changed back to the 17 for a few days. It worked okay but the rider said he would have to downshift sometimes a long uphill. Changed to the 16 and it was perfect until we crossed the Great divide. Changed to the 14 tooth sprocket. Up and over with no problem. Back to the 16 for the rest of the trip.
I never figured out ratios. All by the seat of the pants. No tachometer either.

I did not see any other teams changing gearing.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/29/17 6:18 pm

Originally Posted by RPM
We changed the motor sprocket on the 1915 Norton....
Thanks very much for this information about your gearing experience. It's very helpful.

I haven't taken my primary cover off yet so I don't know how fast/slow it is to get to the engine sprocket. Or, how easy/hard it will be to find replacement ones in different sizes. That's why I discussed the rear sprocket since I could easily machine a generic aftermarket one to fit. Of course, a tooth or two on the engine sprocket makes a much bigger difference than on the rear one.

If only it had the optional 6-speed with fuel injection and electric starter...

Posted By: johnm

Re: Technical questions: 1928 Ariel Model C - 05/30/17 12:30 pm

Having changed the rear sprocket many times for gearing on different circuits - taking the wheel off and on and off and on - I have often been tempted to try a split rear sprocket. But I have never tried it mostly because on a race bike everything is being pushed to the limit and something might break.

But on a 1928 bike would it be worth a try? You would have to machined up a couple and carry two chain lenghts but that's not too difficult.
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 05/30/17 5:39 pm

Although an old bike, its not a veteran, I think you will find it has a good performance and enough gears to cope. I would worry more about its ability to keep cool on a long mountain climb, These bikes were expected to give outstanding fuel economy and usually ran a bit weak to achieve this, ethanol laced fuel seems to make this critical. Modern piston clearances and valve guides may give more trouble than well worn orriginal bits, A phenolithic carb spacer may be usefull.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/30/17 8:00 pm

Originally Posted by norton bob
I think you will find it has a good performance and enough gears to cope.
I hope you're right.
Originally Posted by norton bob
A phenolithic carb spacer may be usefull.
That's a good suggestion. Thanks.
Originally Posted by johnm
a split rear sprocket.
That's another good suggestion. Although the small difference between the diameters makes things tight it looks like that might be a workable solution. It certainly would be easier to change the gearing that way than either removing the wheel to do it, or changing the engine sprocket.

That still leaves the optimum overall gearing to be determined. I have it from three sources, including one who's on Britbike, that a 'QL' gearbox like mine has a big jump from 2nd to 3rd. With standard overall gearing the bike has to be wound out to ~35 mph in 2nd before shifting to 3rd. It then slowly builds up steam until ~40 mph at which point the power starts coming on again. In other words, at 37 mph the engine would be screaming in 2nd but lugging in 3rd. The two obvious places where this 2nd/3rd gap matters are when traveling through towns and when climbing the Rockies.

Absent a 'QW' gearbox showing up I'm stuck with this ~5 mph gap, although it could be moved up or down the speed range by adjusting the overall gearing. The question then becomes, where will positioning this gap be least obnoxious? Any thoughts on this would be greatly appreciated.

If Norton Bob is right that the gearbox ratios will be OK, it still could be worth altering the overall ratio. Using a larger crankshaft sprocket (if ones that fit are available) could move the 2nd/3rd gap up to, say, between 40 and 45. That seems like it would be better for times I'm in traffic (assuming that change doesn't make 1st too high). However, in hilly or mountainous country it seems like having the gap at an even lower speed, like 30-35 (or even 25-30), might be best. Again, thoughts on this would be appreciated.

Note that whatever overall gearing is used, bolting on a 10.5" dia. rear sprocket would drop that overall ratio by ~16%, i.e. would move the gap down by ~ 5mph. Unfortunately, there isn't enough room for a large enough bolt-on sprocket to make more than a ~16% change. This means that using the rear sprocket alone the overall gearing couldn't be set for a gap between 40-45 in the flatlands and changed to 25-30 for the mountains.

Again, the question is, since there will be a 5 mph range where the bike will be sluggish, where would you position that gap if you were me?

I'm tied up today but will try to start putting a few miles on it tomorrow. There's no good substitute for actual experience with it on the road
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 05/30/17 8:25 pm

These old bikes usually have plenty of pull and flywheel , and "dig in" on hills, I know my 36 Rudge is a bit diferent but even with loads of mechanical issues to be sorted it still charges off with vigor and lets me know its closely related to the 1930 bike that did 200miles in 2 hours.My Ariel was a very rough girder 350 field bike bought for £3.50 , Never did a thing to it and it carried me back and forth to the rocker cafe for months at 50mph. No faster as it would otherwise take charge and frighten the life out of me.
Posted By: Villiers

Re: Technical questions: 1928 Ariel Model C - 05/31/17 1:15 am

Hi,
I've been lurking and following the discussion with interest until I just can't help sticking my nose in. I've run bikes with 3-speed Sturmey Archer and 3 speed Albion for a long time and the same issue of compromise gearing arises with all. It's not hills that are the issue, it's long slow inclines just a tad too steep for high but not needing the big drop to middle. I end up plodding up long shallow drags at walking pace rather than have the engine screaming it's head off. I live in Australia which is not renowned for big hills but certainly seems to have its fair share of the long slow inclines I'm moaning about.. .
I would unhesitatingly gear for the long ride across country and let the Rockies take care of themselves. They are but a small proportion of the trip. I think keeping up your average so you get there on time will serve you best.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 05/31/17 8:41 pm

Originally Posted by Villiers
I would unhesitatingly gear for the long ride across country and let the Rockies take care of themselves.
I've now put ~10 miles on it up and down the 2 mile neighborhood street, including a couple of hills and my steep driveway. I've been back for an hour and I still have a huge smile on my face.

Unlike a modern motorcycle where all you have to do is glance in the rear view mirror every once in a while, with the Ariel it feels like there are a hundred things competing for attention all at once. Also, it's one thing to know my neighborhood street is rough, but I didn't truly appreciate just how rough it is until today's ride on a rigid frame bike.

Notes after first lap:

Wire the rear stand up
Add rear view mirror
Add speedometer


Additional note after second lap:

Very securely wire the rear stand up

Despite the rear stand being knocked loose more than once the saddle is quite comfortable and "unbouncy." A firm grip on the handlebars, though, would soon knock bones from their sockets.

I'm now fairly comfortable with its Bronze Age drip feed irrigation system. If I don't turn the knob quite far enough no oil drips in the sight glass. If I turn it not very much further a steady stream develops which from the rider's position looks the same as no oil dripping (unless examined closely, which is impossible to do on a rough road). If I stop for any reason (like to return the rear stand to its seemingly-strong, but too-weak clip yet again) the oil doesn't start dripping again for what seems like forever, but is actually is maybe 5 sec.

Even though it felt like 50 I doubt if I even touched 25 at any time so all I could confirm is that it does have a 3rd gear. However, the engine has plenty of power so I'm now less concerned about optimizing the gearing. I discovered in my 'shop manual' last night that the standard gearing was a 23T engine sprocket, with 21T for 'solo, hilly country' and 19T for 'sidecar'. First gear feels fairly high so I suspect I'll find mine has the 23T. All the better for loping across the Great Plains.

The small catch bottle I put on the end of the breather connected to the timing case didn't collect anything, but this time I had laid out a large piece of cardboard to park it on and it collected quite a bit of oil, all of which is dark, old stuff. This must be coming from the other engine breather whose existence behind the primary cover I have yet to confirm.

As soon as I get a rear view mirror and speedometer installed it will be ready to venture further from the neighborhood. For now I'll hook up a cheap Chinese bicycle speedometer but longer term I'll want a more elegant solution. Making this difficult is the QL gearbox doesn't have a speedometer drive. Speedometer suggestions gratefully appreciated.

p.s. both brakes suck. Relining with modern material and arcing to the drum is a must-do item.
Posted By: Villiers

Re: Technical questions: 1928 Ariel Model C - 06/01/17 1:47 am

Time is of far more importance than speed. How much time do you have to the next check point? Are you on time, behind time or ahead? An old fashioned gentleman's pocket watch mounted on the handlebar is far more useful than a speedo and easier to read than a digital thingie. A second watch in your pocket lets you check the accuracy of the first. Things are even easier with an enduro style trip meter that can be reset back to zero at every check point, Easily driven off the front wheel with a standard vintage accessory speedo drive.

Secondly, did you replace the grease nipples in the front end and grease it properly? Even if you did it will take a good hundred miles for everything to free up nicely whereupon the ride will steadily get smoother but still only to a standard where you will understand why tele forks were such a popular improvement.

Thirdly, there is a natty little channel in the primary chain cover of my '26' Matchless that catches the breather drippings and directs it onto the engine sprocket and chain. You may have something similar. Oil does not necessarily drip straight out of the breather on to the ground.

Fourthly, do not leap into re lining your brakes. Most modern linings are far too hard for these beasties. You will get far better results from very soft linings. They will work very well except possibly for descending the Rockies. It's another compromise. Good brakes for 95% of the trip but possibly hair raising for the 5% you really want them. Then again, if it was easy it'd be no fun would it.
Cheers,.
Posted By: franko

Re: Technical questions: 1928 Ariel Model C - 06/01/17 1:15 pm

Just a thought about the brakes on bikes from this era.
If I remember correctly someone had written and asked Bob Currie (sp) why the front brakes were so poor at stopping on the older bikes.
He answered that it was by design because of the road surface at the time they were built was made of cobble stone, wood block or other such surfaces that became slippery when wet.
The rear brake being stronger was to keep the front end from sliding out with the brake locked up.
A little more information as you decide how to address the issue.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/01/17 4:49 pm

Originally Posted by Villiers
How much time do you have to the next check point?
It's not an event like that. Roughly 125 miles to a lunch stop, and another 125 to the next overnight stop. We just have to get to those two points each day by a given time or sooner with no other checkpoints along the way.

Originally Posted by Villiers
Secondly, did you replace the grease nipples in the front end and grease it properly?
It had unknown-to-me grease fittings when it arrived, but as soon as zerks showed up I greased everything with the closest modern equivalents to what Ariel recommended.

Originally Posted by Villiers
Thirdly, there is a natty little channel in the primary chain cover of my '26' Matchless that catches the breather drippings and directs it onto the engine sprocket and chain. You may have something similar.
The breather tube at the end of which I put a catch bottle is a continuous tube. If anything had come out of it I would have caught it in the bottle. However, hidden under the primary cover is another breather that is intended to oil the chain. And, apparently, the driveway and everything else within a 5 ft. radius.

Originally Posted by Villiers
Fourthly, do not leap into re lining your brakes. Most modern linings are far too hard for these beasties. You will get far better results from very soft linings.
Originally Posted by franko
asked Bob Currie (sp) why the front brakes were so poor ... He answered that it was by design
There's no way I would cross the U.S. with the present brake linings. I've had Michael Morse of Vintage Brake do the brakes on three of my bikes over the past 20 years and I've already arranged a place in his queue to have him reline both of the Ariel's brakes and turn them to the dia. of my drums. Before I send him the backing plates and shoes I'll turn the drums to remove any possible distortion and supply the dimensions to Morse for his work. Take a look at www.vintagebrake.com/info.htm.

I've read and heard contradictory advice about the interaction of the front brake with girder forks, and my own half-vast personal experiences with girder forks totals the ~10 miles I rode yesterday, So, if falls to me to estimate the effects of mechanical forces myself.

One could say the Ariel's forks are triangulated, but the angle of the triangle is so narrow that the fore-aft rigidity can't be much better than if it had telescopic forks made with the same total cross section of steel, i.e. pretty low. So, when clamping on the front brake I can expect the forks to bend backwards by a significant amount. The stronger the clamping action of the brake, the more the legs will bend. This is a particular problem if the drum isn't perfectly round because in that case the braking force will oscillate with each revolution. The combination of an oscillating force and springy legs of steel would make for "interesting" behavior.

Having a really poor front brake would eliminate the lack of rigidity as an issue even for an out-of-round drum, but having dual Brembos even with warped disks would maximize stopping power. The optimum solution for a girder-forked bike lies between those two extremes. Based on my half-vast experience, I believe that solution to be proper modern linings arced to the diameter of drums I will have turned to make as cylindrical as possible.


The Ariel now has a rear view mirror and a bicycle speedometer so it's ready to venture further into the world. Today, though, I plan on spending some quality time with a Catalina.
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/02/17 7:00 am

I found the front brake on my Rudge to be totally useless, so much so that I was sure it was full of grease. however once I had swopped the shoes over so that the thicker one was in the leading position all was well, I now regularly swap shoes around and use a caliper to check which shoe is best. The girder damper needs adjusting to the speed ,so its one more thing to do, tyre pressures are critical and 20 in the front seems to work with Avon speedmaster .,Any more and its too bouncy. All seems far too busy till I reach 60 and slip into top when it turns into a smooth magic flying carpet!!.
Posted By: Villiers

Re: Technical questions: 1928 Ariel Model C - 06/02/17 12:58 pm

In the end I find the effectiveness of the front brake rises and falls on the girder fork set up. No matter how much care I put in to it for it to work effectively the wheel must be firmly on the road and it's all too easy to have it dithering all over the place. The lack of anything approaching modern damping means getting the friction damping and tyre pressure just so to keep the wheel on the road, exactly as Norton Bob says. I think you really begin to appreciate the fine balance needed to have all components give of their best and how much it differs from bike to bike.
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/02/17 5:44 pm

Friction dampers can easily become contaminated with the grease for the links, this ruins there performance. On the Rudge the spring is concealed in a tube and these have been modified to include a hydraulic damper, crafty yes?. Modern sintered linings will wear out hens teeth rare hubs.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/03/17 12:24 am

Originally Posted by norton bob
once I had swopped the shoes over ... all was well
The girder damper needs adjusting to the speed ,so its one more thing to do
Originally Posted by Villiers
In the end I find the effectiveness of the front brake rises and falls on the girder fork set up.
That your braking improved when you simply swapped shoes is why I'll have mine arced to the measured diameter of the drums.

On a more general note, it's easy to dismiss any aspect of performance that's less than desirable as due to it being "a 1928 motorcycle." Certainly there are limitations because of the engineering of that age, but my approach to work on any bike is to try to understand the intrinsic limitations (as opposed to extrinsic ones, such as manufacturing tolerances or defects, wear, lack of proper lubrication, etc.) and then look for solutions that give the best possible performance within those intrinsic limitations.

As an example, compression and rebound damping of any fork, including telescopic, affects performance. Unfortunately, an intrinsic limitation of my 1928 Ariel is tension on the friction discs is set with a nut and lock nut so adjustment on the fly isn't possible. In tests on different roads and speeds I'll have to determine the "best" friction setting and then live with that setting on whatever road surfaces I later encounter. Of course, on the side of the road I could change the damping if I decide it's needed, or possibly swap the lock nuts for a knob. Further, the manual says to "inspect and replace" the friction discs at 4000 miles which tells me I'll likely have to compensate for wear over the course of the 3750-mile Cannonball.

As for other aspects of fork setup, when I take them apart I'll accurately measure them (I have an appropriate surface plate and measuring instruments), remove any small twists or bends (30 ton press), line bore to eliminate any binding of the spindles (mill), properly adjust the headstock bearings and taper roller wheel bearings on assembly and again after a few hundred miles, etc. These efforts should result in a girder fork that will work as well as any fork of this design possibly can.

Originally Posted by norton bob
On the Rudge the spring is concealed in a tube and these have been modified to include a hydraulic damper, crafty yes?.
For better or worse, I'm approaching this as an exercise in experiencing what it's like to ride an original-as-possible 90-year old motorcycle across the country so I'll be sticking with the friction damper.

Of course, I'll be on modern tires and I'll also use LED lights and modern oils and greases. However, even if original 1928 tires in un-degraded condition were available, safety depends too much on tires and brakes for me to insist on being 100% period-correct for items like these. For similar safety reasons I installed a later, larger tail light assembly (Lucas L529) for its greater visibility than the one supplied as an accessory in 1928. I want to experience riding a 1928 motorcycle, not dying on one. Although a Magdyno was an optional accessory in 1928 we won't be riding at night so keeping the stock magneto is my preferred choice and LEDs will allow me to do that.

Approached as a competition I would want every upgrade that's possible to slip by inspection. However, I'm approaching this as an experience riding a 90-year old motorcycle across the U.S. so I only want the upgrades that I feel are prudent to have.

Turning to recent progress, I learned today the semi-liquid grease for the gearbox has been delayed until the end of the month. So, to be sure all is OK until then I added a large dollop of 50W to the grease in the gearbox. No doubt some will ooze out to join the other oil puddles but some should stay in and help with the lubrication. Although the Ariel is ready for its next outing a daughter borrowed the pickup for a horse show so I won't wander too far from home until she returns it on Sunday. This also means I'll spend some more time with the Catalina.

Posted By: Alan_nc

Re: Technical questions: 1928 Ariel Model C - 06/03/17 8:27 pm

Back to brakes for a moment:

Even with turning I would use the old chalk on pads method of making sure the brakes fit the drum. Chalk the pads, spin drum while engaging brakes, check to see where chalk has worn off, sand down clean area - repeat - repeat - repeat...until pad is cleaned evenly.

Makes a big difference.

Just my .02
Posted By: Bruce Martin

Re: Technical questions: 1928 Ariel Model C - 06/03/17 11:38 pm

Originally Posted by Alan_nc
Back to brakes for a moment:

Even with turning I would use the old chalk on pads method of making sure the brakes fit the drum. Chalk the pads, spin drum while engaging brakes, check to see where chalk has worn off, sand down clean area - repeat - repeat - repeat...until pad is cleaned evenly.

Makes a big difference.

Just my .02



Thanks - I'll try this on my '37 Ariel Red Hunter with a very poor front brake despite which I actually ride.

Bruce
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/04/17 3:31 pm

Originally Posted by Alan_nc
Chalk the pads, spin drum while engaging brakes, check to see where chalk has worn off, sand down clean area - repeat - repeat - repeat...until pad is cleaned evenly.
That's a good idea. Thanks for suggesting it. Wait! That would mean additional work for me. That makes it a bad idea...

On the subject of work, when contemplating the bike on the lift it struck me that it doesn't appear possible to remove the rear wheel without either raising the bike further off the ground than possible with the stand, or laying it on its side and working fast before all the fluids leak out of the tank. Maybe looks are deceptive and there actually is enough clearance to get the wheel out of there. It's hard to imagine a design that wouldn't allow this, but stranger things have happened. However, if not, it would be problematic to repair a flat on the side of the road.

I mentioned this to Shane in Oz, who noted that reproduction, hinged BSA M20 mudguards are available. His suggestion triggered a neuron that already should have fired on its own, leading me to the garage where I have two original M20 mudguards, and a box of assorted stays, on the shelf.

Conveniently, an M20 mudguard has the same 6" cross section as the one on the Ariel as well as the same radius. As a result, it appears it would be relatively easy, as these things go, to adapt one of them to fit. However, both M20 mudguards have issues that would have to be dealt with before either could be used. One is rusty, but otherwise complete. The other is missing the hinge and has the two pieces held together with screws. Although I could grind the rivets off and swap the hinge from the other one, there are still cracks that would need repair.

For the moment, at least, I decided the rusty one seems most promising so I bought the largest pan I could find at a "dollar store" and ~1/4 of that mudguard is currently marinating in a molasses/treacle solution. Based on my previous results it should be about a week before I can rotate the mudguard to immerse the next 1/4. And so on. Depending on how it looks when this process is done I may or may not use a rust conversion primer, but at the rate treacle works I have a month to decide on that. Also, I have a month to determine whether or not the wheel can be removed without having to modify the bike.

If nothing else, the process of patching thr M20 mudguard would let me improve my metalworking skills using a component that needs to be functional but doesn't have to be perfect. However, even though it would be largely "camouflaged" by other parts of the bike I still would work to make my repairs as invisible as possible.



p.s. The owner of another Black Ariel responded on the AOMCC website that his is high enough on the rear stand that it indeed is possible for him to extract the wheel. I'll know myself later this month when I remove it to arc the drum and measure it for Vintage Brake to arc the linings when they're installed later this summer.



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Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/05/17 3:18 pm

In the Uk many of the roads have pavements that are raised above the road surface, this helps if you have to remove a wheel as you can put the bike on the pavement and swing the wheel over the road. I also carry (in the pannier) some wood blocks.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/06/17 7:15 pm

Rust never sleeps, but neither does molasses/treacle. I checked the progress of my very rusty M20 mudguard last night, after 2 days + ~4 hours, and the rust was completely gone from the section that had been immersed. However, I wasn't prepared to do anything further with it at that point so I left it immersed overnight and today rinsed that section in water while lightly scrubbing with a Scotchbrite pad to help remove the residue.

I then placed the next ~1/4 of the mudguard into position in the pan for its turn in the solution, which has left the freshly de-rusted metal unprotected in the air. Although it might acquire a thin coating of rust over the next week, I'll be welding the mudguard when this is done and removing primer would take more time than removing any small amount of fresh surface rust.

In addition to checking on the mudguard I ordered a set of 2" stick-on vinyl numbers and letters to put my Cannonball entry number on the "pedestrian slicer." Although it doesn't sound like I accomplished much on the Ariel yesterday, because I didn't, even on days when I don't have any time I'm doing my best to try to at least do something to move forward.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/08/17 4:25 am

I've only discussed the rear tire so far but there's the front tire to consider as well. If the bike were supported at its normal height there is just enough clearance to roll the front tire out from under the mudguard. So, yesterday I fabricated a portable jack for this purpose from 1-1/4" dia. Al and a "foot" for leveling machinery (if only there were reasonably easy way to upload pictures there would be so much to show...).

The 2" vinyl stick-on numbers and letters arrived yesterday and I applied them in the form of my initials followed by my 3-digit Cannonball number. That may not sound like much of an accomplishment but the letters aren't easy to work with so it took quite a while to do a halfway decent job with the layout (it would have taken even longer had I done a fully-decent job...).

Today I made some progress devising an age-appropriate speedometer solution. Details to follow in the weeks to come as the components arrive and I piece them together.

Meanwhile, the mudguard has been back in the molasses since yesterday to de-rust the next section.


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Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/08/17 5:12 am

On my 36 bike the front mudguard stay/stand allows the wheel to be removed if turned to one side, Yours looks similar.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/08/17 6:00 am

Originally Posted by norton bob
On my 36 bike the front mudguard stay/stand allows the wheel to be removed if turned to one side, Yours looks similar.
The lower stay on mine unbolts from the mudguard so if the forward bolts are loosened it would pivot down and support the front end off the ground and allow the tire to be removed. But, only if I am able to lift the front of the bike straight up. I'm sure that's what is intended by the design but, since that is half the weight of the bike, it would mean having to lift ~150 lbs. from an awkward position. The jack I made is to avoid having to (try to) do that.
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/11/17 8:52 pm

My Rudge has a box with bushes and needle rollers , plus a small amount of oil set low in the box. It needs thin oil to splash around but has poor sealing . The answer is to top it up very regularly. They are all different.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/12/17 5:09 pm

Originally Posted by norton bob
It needs thin oil to splash around but has poor sealing . The answer is to top it up very regularly.
That's a good tip. Thanks. The inspection cover on my Burman gearbox is held by four easily dropped nuts and with half the cover obscured by the toolbox. I'll probably machine a new cover that includes a smaller one in the non-obscured area held with a single wingnut to make inspection and topping up easy.

I fabricated an "air cleaner" from fine stainless steel mesh to go over the inlet trumpet. The mesh will keep anything larger than a fat mosquito from being sucked into the engine and might serve as a backfire flash suppressor, which could be helpful since I don' t plan to wear asbestos chaps.

I replaced six grease fittings with Zerks. In addition to the two for the rocker arms that I already replaced there are four on the forks and one each on the hubs. Installing the Zerks actually took quite a while since all of them were 45-deg. fittings and only two ended up pointed a useful direction after being tightened. That meant I had to index them using washers of various thicknesses not unlike adjusting the valves on a Ducati. Luckily I have a good supply of fasteners so I calculated the thicknesses I needed based on the 26 tpi pitch and then went through my 1/4", M6, and fiber washer drawers with calipers to select washers. In the end I decided 90-deg. would be better for a couple of them so those are now on order.

I can't find that I ever received an answer to my question about modern equivalents for the greases listed in the Owners' Manual so I sent requests to three oil companies for their recommendations. I said it would be used for roller bearings up to 1000 rpm and supporting ~ 75 lbs. ea. and as well as described the motion of girder shafts in bushings without mentioning it was for a motorcycle My own reading of the specifications already had led me to lithium-based greases of NLGI consistency grade 1 ("soft"), and the specific example I had written down was Mobilgrease XHP 221. Interestingly, Mobil was the first (and only so far) to respond and their recommendation was XHP 222, which has all the same properties as 221 except it is NLGI 2 ("normal" consistency).

The greases Ariel recommended all have "soft" or "light" in their names which is why I thought XHP 221 was the better choice. That said, for all I know what was a "soft" grease 90 years ago might well be considered "normal" today. Anyway, since I have the attention of someone at Mobil I sent that rationale to him along with a question that, assuming "normal" XHP 222 was "perfect" for a particular application, what would be the downside of using "soft" XHP 221 instead (or vice versa)? I await his response.

The M20 mudguard is presently in the molasses solution to de-rust the final section. Whether or not I'll actually use it depends on what I find about removing the rear tire when I'm ready to start the rebuild, or when I need to send the backing plates to Vintage Brake, whichever comes first. I'll put it aside until then. If I don't need it I'll use a can of etching primer I bought yesterday and put it back on the shelf without taking the time to patch the rust damage.


Question: in England is "flat tank" used interchangeably with "vintage" (i.e. pre-December 1930) for the purposes of entering events? That is, if there were an event for "flat tankers" would a 1928 saddle tank Ariel be unwelcome? I don't have any specific event in mind so this is just a general question about terminology used in England.


p.s. The Mobil guy responded to my question about 1 vs. 2. He pointed out that neither 1 nor 2 is especially soft or hard because both are in the middle of the NLGI range of 000 to 6 so they don't differ by very much in consistency. He said the worst consequence of a softer grease is not staying in place as well on poorly sealed bearings. Not that any bearing on my Ariel could possibly be poorly sealed...

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Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/12/17 6:37 pm

In the Uk there are club runs for girder fork machines , flat tankers, veterans and bikes over 25years old.Pre 1940 etc The term vintage is not very specific and means different things to different people.A flat tanker or an old saddle tank bike could both be vintage , although one be 1915 and the other 1965. Your machine would not be in the running for an award in a flat tanker event. But would be welcome in any old bike rally.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/20/17 3:21 pm

Originally Posted by norton bob
Your machine would not be in the running for an award in a flat tanker event. But would be welcome in any old bike rally.
Thanks for this information. Pre-1940 British bikes are rare enough in the U.S. that if anyone organizing a rally got too picky about dates they would be unlikely to have more than one bike -- if that many -- in any given category.

I was in Russia this past week so I was only able to make a little progress on the Ariel. I'm piecing together the components to install a period-appropriate front wheel speedometer drive. It's not like it's essential to have this but it's the sort of thing that would be a nice touch on this bike (rather than the present $1.99 Chinese bicycle speedometer...).

I have the various pieces on their way to me now and will use the drive with a Chronometric until/unless I run across a period-correct Watford or Bonniksen. I'll have to machine my own drive sprocket to match the ratio as close as possible to that of the speedometer but I have a dividing head so that won't be a big deal.

It looks like the drive sprocket will need ~20 teeth which means jumps of ~5% between adjacent ratios. Since typical Chronometric ratios are in the range ~1450-1650, with luck, I'll find a speedometer in my collection with a ratio that allows me to hit somewhere in the middle of the spacing between gears so ~2% accuracy should be within reach (or, with real luck, even better).

I'll need to machine my own mounting bracket for the Smiths angle drive so if any of you could post a picture of such a bracket (or a web link showing one) I'd appreciate it. It's not like designing a mounting bracket is a big deal but I'd like to make one that looks reasonably similar to an original. Although photos of such brackets may be all over the web I haven't been able to find any.

I returned from this trip to find a note in the door from FedEx saying they had made the third and final attempt to deliver a package containing the headlamp housing. However, I re-entered in their system for another delivery attempt and got confirmation that will happen tomorrow.

Anyway, despite not having been here for a week progress didn't come to a complete halt.

Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/23/17 4:03 pm

Along with preparing the bike I've starting giving some thought to the logistics of the event. Leaving aside the actual two weeks of the Cannonball itself, there's the issue of getting the bike, riding gear, tools and me to the start, and home again from the finish.

One approach would be a crate to hold the bike and everything else (except me). Pulling numbers out of the air for the moment, I'll guess that would cost $600 each way x2 =$1200. Assume $800 for the plane tickets and the total for that approach would be ~$2000. It also would require volunteers near the start and finish who could store the crate for up to a week depending on the shipper's schedule.

To get an estimate for another approach I got on-line quotes for one-way rentals to/from ME and OR of a 12' truck (bigger than needed, but possibly(?) smaller than desired as a support vehicle on the Cannonball) of ~$850 + 670 = ~$1500. Add food and motels for the six 12-hour days on the road that google maps says it will take from the Southwest (~$600) and gas for the 4200 miles (/12 mpg x $2.50/gal. =~$875) and that's ~$3000 total to get the bike, tools, riding gear, etc. from/to home.

Finding a smaller truck, looking for better rental deals, keeping the same truck for the full Continental circumnavigation, etc. might cut that somewhat, but driving still means a grueling 6 days on the road trying to cross the continent W to E and N to S at warp speed. Since the truck would be big enough, another entrant in the Southwest to share the cost and driving for the portion before and after the rally might be an option, but that would entail a gamble on compatibility and would require someone who has other plans for a support vehicle during the rally since once at the start I will be sharing a support vehicle with a European friend.

The issue I'm asking about is how best to handle the transportation before and after the Cannonball. Suggestions from people who have dealt with this, or something similar, in the past would be greatly appreciated. Thanks in advance.
Posted By: kommando

Re: Technical questions: 1928 Ariel Model C - 06/23/17 5:01 pm

Whatever the solution being rested and raring to go on start day must be an advantage, does not matter at the end. So maybe helper gets the bike and equipment there and you fly in, both sharing on the return.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/24/17 12:19 am

Originally Posted by kommando
being rested and raring to go on start day must be an advantage, does not matter at the end.
I half agree. I suspect at the end I'll want to pour my aching body onto an airplane and be transported as quickly as possible to my own bed for a long rest.
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/24/17 10:31 am

Thinking about the long hours riding, a comfy position ,a non slidey seat set far enough back so your legs not spread to much , a light clutch (tennis elbow!) and a throttle with a non slip grip ,a light spring and one of those clips that you just rest your thumb on would help.Also need an erganomic position for knees and ankles and a mirror without the shakes.Tear off visor or at least cleaning spray and microfiber cloth.My visor has a stick on sun strip for riding into glare,a life saver. 50 factor sun creem , a silk neckerchief, Wet wipes , Sudacrem( very usefull if you have to change a nappy)or get an upset tum drinking strange water. .Don't know how you can carry a porta potty!!.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/24/17 1:45 pm

Originally Posted by norton bob
Thinking about the long hours riding, ....
I'm sure I would have thought of all of your suggestions myself. Unfortunately, I only would have thought of them after the rally was underway and it was too late for me to do anything about them. So, keep your excellent suggestions coming.

Although I had originally thought of piecing together a bitza for this event I'm grateful I got a bike that is already complete and running because, with only a little over a year left to go, it is going to be tough enough as it is to get it complete and running.

Yesterday's progress was to machine a pair of stainless fittings needed to mount the headlamp. I can't think of anything remotely equivalent in the mounting systems on later bikes, but there are two "eyes" on the top of the forks where the headlamp brackets attach. If you squint you can just make this out on this and this image on the web. The eyes are about 0.8" in length and the inside is tapered from just under 5/8" at the front to just under 1/2" at the back. A matching taper on the headlamp brackets allows them to be pulled into the eyes using the internal threads of the brackets.

Although the tapers were coated with fairly thick paint I used the shanks of drill bits to measure the starting and ending diameters as best I could from which I calculated the taper as 5.08-deg. I guessed (incorrectly) that it was 5.7-deg (i.e. a taper of 1:10, like on a magneto shaft) and turned this taper into a 5/8" Al rod as a test gauge. In the end I made 5.7, 5, 4.5 and 4-deg. gauges (not in that order), each taking only a couple of minutes, before deciding 5-deg. was the best overall fit in the two slightly different eyes.

After determining the taper I machined the two fittings from 5/8" stainless. I made them 1" long with the taper covering 3/4" of that, a 1/2"-dia. hole 1/2" deep in the front, and tapped 1/4-20 in the back to use to draw the fittings into the eyes when finished. However, I'll probably retap them 3/8-16. The spacing between the eyes is narrower than the later, replica Lucas DU42 headlamp housing I'm using (4" and 6-3/8", respectively) so I'll need to make appropriate bends in some 0.036"-wall, 1/2" OD stainless tubing that I'll then braze into the fittings to complete the brackets.

I spent at least 3 hours yesterday just getting these two fittings measured and made, and there's a lot more to do before the headlamp is finished, which is why I'm grateful the Ariel already is complete. I'm also grateful I have the tools needed to complete the completed bike.

On another note, I realized I should order tires ASAP so I can mount and balance them while I have the wheels off to turn the brake drums, so suggestions for appropriate ones for this ride would be appreciated. For my other British bikes I have been more concerned with either reasonably authentic appearance or good performance on twisty roads (i.e. sticky, but rapid wearing), but for the Ariel I want ones that will have a safe amount of tread left at the end of ~4000 miles of mostly-straight riding and moderate speeds through curves. Not that it ever rains in Oregon, but in case it does, having tread is far more important that period-correct appearance or the brand on the sidewall.

p.s. Cautions about not using spoke tension to correct for alignment, warped rims etc. aside, and recognizing they all won't be the same when finished, what is a reasonable torque value to aim for?



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Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/24/17 3:44 pm

For my 99 and 500Rudge I have avon tyres which although the old 1950--1960's pattern are made with modern rubber and are availiable in the old sizes 19 and 20 inches and not too wide which can be a problem if the bike has only enough room for a 3.50 wide tyre. The modern equivalents all turn out too wide , The old stile tyres also have a much deeper profile ,modern tyres sit the bike about 2" lower wich also affects the gearing. The milage is also good.. Last year I was chasing some Commandos round Brands Hatch and they did not get away from the old 99 on Speedmaster front and SM rear.Don't Know if your bike has rim locks ,I use them as they save the tube being ripped to bits if you pucture at speed..Don't use cheap tubes . Get the Best.
Posted By: Alan_nc

Re: Technical questions: 1928 Ariel Model C - 06/24/17 4:29 pm

Don't know what outer wear you are planning but a couple of thoughts. I had a perfectly good completely black 3/4 length jacket but after a close call went to one of those neon colored jobs. I bought a waist length and have never been happy with it. All waist length jackets seem to bunch up in the front. I don't know if there is a suit that would be comfortable enough to wear in all weather including rain but that sure would be an advantage if you did not have to carry rain gear. The BMW store/magazine has some that are supposed to be all season.....have not tried them but someone that has may chime in with a comment. Like any sport or event I hope you get to do a few semi-long rides just as you plan to do the event. Nothing replaces real life.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/24/17 6:15 pm

Originally Posted by norton bob
The milage is also good... Speedmaster front and SM rear
"Good," as in more than 4000 miles and still with adequate tread?

Not that I will use them, but the bike came with a ribbed 3.25x19 Cheng Shin on the front and a Balum BT 3.50x19 on the rear. I can't find a DOT code on the front but the rear one is ten years old.

Originally Posted by Alan_nc
Don't know what outer wear you are planning but a couple of thoughts....
...an advantage if you did not have to carry rain gear
I've attended the Irish Rally for 15+ years where I learned from experience that a "100% waterproof" label isn't even close to the truth. The Irish Rally covers ~125 miles/day (i.e. half that of the Cannonball) for four days through all kinds of weather (i.e. raining, raining hard, misting, sunny and uncomfortably hot for an hour before raining again, ...) so I have relevant experience with what works for me, and what doesn't. I prefer a layering approach that includes carrying rain gear separately rather than wearing "waterproof" clothing all the time.

Starting two years ago I got fairly serious about having padded gear as part my regular routine when riding. I use a thin, ventilated Bohn jacket when it's too hot to ride in a regular jacket, and use it as an "under-jacket" when it's cooler, as well as Bohn shorts and pants. I typically use Alpinestars padded jeans on day rides. I wore this gear when I rode the Ariel only a short distance in the neighborhood a few weeks ago. It's part of my plan to take "reasonable" precautions to maximize the chances I'll be able to keep riding for as many years as possible. I also have serious leathers, but any safety gear I'm actually wearing is way better than safety gear I'm not. Anyway, I'll be wearing this stuff on the Cannonball.

Originally Posted by Alan_nc
I hope you get to do a few semi-long rides just as you plan to do the event.
That's certainly the hope.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/26/17 4:42 pm

For the two kinked headlamp stays I traced the pattern I needed -- two offset straight lines connected by a third at an angle -- in a wood 2x4, cut it with a band saw, and used a 1/2" ball end mill to make the 1/4"-deep cavity in each needed to bend the 1/2" stainless steel tubing into shape. However, at that point I learned that wood is no match for this stainless tubing and a 30 ton press. So, I repeated the pattern in a 1"x5" piece of aluminum. It required a bit of a lashup to hold everything where it was needed as the press did its job, but the results were great.

I next cut one end of each to length and silver soldered them to the lugs. I had already spent a lot of time on these stays by this point so it was measure thrice, cut once. The tubing was 1/2" OD but to allow for stretch when I flattened the other ends where they bolt to the headlamp I drilled a 5/8" hole near the edge of a piece of scrap Al and cut off the edge leaving half the hole. I used this to press flats in the stays to leave a rounded profile like on factory stays. Of course, I crushed a test piece of tubing first to make sure it gave the result I wanted

Everything went together nicely. The stainless 0.036"-wall tubing is remarkably stiff but the headlamp bucket is a lot of weight at the end of the two tubes that will bounce up and down with the girder. Although this is how the original headlamps were mounted, even if nothing showed signs of distress during test runs it would be risky to count on something not breaking on the Cannonball so vertical brackets attached to the stiffening strap for the mudguard will complete the job. Luckily, these will be easy to make compared with the tapered and kinked horizontal mounting brackets.

I mounted the headlamp and stared at it for a while trying to decide if it would look better with nickel-like polished stainless or if I should paint the stays black. Black won in keeping with the overall black theme of this "Black Ariel."

The wood pattern that failed wasted maybe a half-hour but everything else went smoothly and a professional machinist couldn't have measured and made these stays in much less time than I did. However, if I had to pay a machine shop's hourly charge of ~$100/hr. to make them they'd be ~$3-400 ea.


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Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/28/17 5:06 pm

I decided I should take the time now to make the vertical stays for the headlamp since, as I wrote in my previous post, "these will be easy to make compared with the tapered and kinked horizontal mounting brackets." Unfortunately, that turned out not to be the case. Upon closer inspection what looked like a straight shot between the headlamp and the potential mounting points on the mudguard turned out to have some of the girder in the way. This means the additional brackets will require more time to make than I want to spend on them at the moment.

Meanwhile, 90-deg. zerks arrived to replace incorrect ones sent earlier and I installed two of them where needed so there's now easy access to all zercs with the grease gun. Also, a liter of old fashioned GL1-grade 90W gear oil arrived so all I need is the Morris semi-fluid grease, due any day now, and the Burman will be ready for longer test rides.

I plan to use a semi-fluid grease for the rocker arms that has too low of a viscosity to be constrained by the plunger in a standard grease gun (I know because I tried). So, I machined a replacement plunger from 2-1/4" Al with two O-rings ea. for the piston and the shaft. I also cut an inch or so from the spring to reduce the pressure on the grease because it doesn't need much pressure at all to encourage it to flow. Previously, I had made a similar modification to a mini-grease gun that I'll carry with me in order to lube the rocker arms, valve stems and tips, and pushrod ends at every gasoline stop.

At this point all the additions and modifications are done that were needed to get the bike up to minimal roadworthy standards (i.e. brake light, headlamp, zerks, carb drip shield, bicycle speedometer, etc.) so I think I'll next turn to the wheels. I'll need to turn the drums and accurately measure their diameters so they're ready for Vintage Brake when he's ready for them. I'll also want to install new tubes and tires when the wheels are off so please read the last paragraph of my 24 June post and give me additional recommendations. Thanks.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 06/30/17 12:28 am

Although no single task reached completion today I made lots of incremental progress.

A period-correct Smiths external 90-deg. speedometer gearbox arrived in the mail. I already have the bolt-on accessory sprockets to use with it but I assumed I would have to machine a new gearbox sprocket to get the correct ratio. However, I lucked out because the gearbox has a ratio of 1.5:1 which, ahem, turns out to give a final ratio of ~1600 turns/mile, nicely matching that of most Chronometrics to within the accuracy of the following calculation:

The exact value will depend on the tire that I put on the rear wheel, but no matter what it will have an OD of ~27" so a circumference of ~7.1 ft. and hence it will make ~747 turns/mile. The two sprockets I have are 56T and 17T so the output of the gearbox will be 747/1.5 x 56/17 = 1640 turns/mile, All I need to do now is machine a bracket to hold the gearbox and buy a cable of the right length. Oh, and repair one of the non-functional Chronometrics on the shelf.

I determined that I can almost remove the rear wheel with the bike on its rear wheel stand. It's on a lift so I used a scissors jack to raise the rear high enough to swing the rear stand into position and then I lowered it onto the stand. However, try as I might I couldn't quite get the wheel out from under the mudguard until I used the jack to raise the stand ~1" off the platform.

If there were a second person he could tilt the bike sideways on one of the feet of the rear stand raising the other side by the necessary 1". But, I can't count on someone else being present if/when if I get a flat so I'll machine a pair of 1-1/2" extensions to temporarily attach to the stand if/when they're needed.

To add to the data in my comprehensive "shop manual" the rear of this 1928 Model C uses a pair of SKF 3K-1163X tapered roller bearings of 9/16" ID. The outer races are SKEFKO (i.e. also SKF) 3K-1120N1 of OD 1-3/4" and thickness 0.56" along with a 0.13"-thick spacer between the race and hub. Also, the shoes are 7/8" wide and the drum is 7" dia.

While the front and rear hubs have zerk fittings they empty into huge cavities (i.e. ~1.5"-diax x 5" long) that would have to have a lot of grease pumped into them before it would reach the bearings. The problem is, if that grease gets past one of the bearings it would fling itself straight onto the brake drum. So, on the principle that the tapered roller bearings on a horse trailer don't need repacking after only 4000 miles, instead of pumping the hub full of Ariel's one-size-fits-all general purpose grease, I'll pack them with a high quality, sticky wheel bearing grease and count on that to last the entire Cannonball.

I won't true the rim until after I remove the tire and as far as I can tell 40-50 in.lb. is the torque I should aim for on the spokes. However, before truing the rim I might first make the jig that will be needed to hold the wheel in order to true the brake drum. Ideally truing should come first because it could slightly distort the drum, but the spokes all seem to be around the right tension now so any effect on the drum should be negligible. But, either way, the tire will come off first.

This brings me to tires. From on-line reviews it appears that any Dunlop or Avon in the sizes I need should be good for 8-12,000 miles which means at least half the tread will be left on the tires at the end of the Cannonball. So, absent someone speaking up quickly and telling me why the following are bad choices, I'm about to order a ribbed 3.25-19 Avon Speedmaster Mark II for the front and a 100/90-19 Avon Roadrider for the rear. Also, three Michelin Airstop tubes (the same size tube is used for front and rear), for air and a spare.

Not for the first (or last time) I'll say I'm glad I'm starting with a complete, functional motorcycle because piecing one together from parts in the time available would not be easy. Beyond this, with a modern motorcycle, like a Gold Star, determining the, say, correct torque for something takes a few seconds. The same task on the Ariel requires conducting a research project. Having to do this for just about every task slows things down a lot.


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Posted By: Tridentman

Re: Technical questions: 1928 Ariel Model C - 06/30/17 1:03 am

Hi MMan, Over the last 55 years I have ridden quite a few bikes over tens of thousands of miles fitted with the Avon ribbed Speedmaster front tires. For the bike you are riding in the Cannonball I think that choice is excellent.
I only fit Avon Roadriders to my bikes these days and IMHO they offer a great combination of road holding and durability.
What I cannot speak for is the combination on one bike----but IMHO I think they will be fine.
HTH
Posted By: Richard Kal

Re: Technical questions: 1928 Ariel Model C - 06/30/17 3:53 am

Re preventing grease from the wheel bearings entering the brake drum:

If your bike is the same as for my 1927 Model A, then the original arrangement does not positively seal the bearing(s) grease inside the hub. My machine has a grease slinger (baffle) riveted to the inside of the brake plate which has minimal clearance around the hub.

There is a tapped in (light fit) thin gauge metal retainer that keeps each bearing cone in place, with a minimal clearance between its ID, and the bearing boss. The minimal clearance is designed to reduce grease passing into the hub. I replaced each metal retainer with a 1 3/4" x 1 1/4" x 1/4" lip seal, and made a thin wall bush (light interference fit) of 1 1/4" OD, to press on the bearing boss. This sealed the grease in the hub.

Did the same for both hubs on a 1938 4G.

To improve the braking, I shrunk a thin cast iron liner into the front brake drum (and pinned it), and modified / machined a cast iron drum off an old Norton, to duplicate the rear drum (with 47T sprocket).
HTH,
Richard
Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 06/30/17 12:16 pm

Hi,

Originally Posted by Magnetoman
about to order a ribbed 3.25-19 Avon Speedmaster Mark II for the front and a 100/90-19 Avon Roadrider for the rear.

Just a thought but, if the original front tyre was a 3.25x19, would the rear 19" not have been a 3.50? And 3.50x19 is available in the Avon SM companion range to the Speedmaster fronts? According to Avon's figures, the Roadrider is around 1/2" wider overall than the SM, and British bike makers weren't generous with space between tyres and non-rotating parts ...

Regards,
Posted By: kommando

Re: Technical questions: 1928 Ariel Model C - 06/30/17 2:41 pm

Rear SM is designed for long life, nickname Skidmaster, had one on my first ever bike and it lasted 2 weeks before changing to roadrunner. They may have changed to a modern compound but I will never buy one to find out.
Posted By: Tridentman

Re: Technical questions: 1928 Ariel Model C - 06/30/17 5:34 pm

Named Skidmaster with good reason iIME!
Actually I bought one only last year---for the rear wheel of my Ural sidecar outfit.
Avon make a sidecar tire but the Skidmaster is available in a wider section so is the "recommended" tire for sidecar use.
I was surprised having received it how square section that tire is.
Thinking of it on a solo would give me the Henie-jeebies!
Posted By: norton bob

Re: Technical questions: 1928 Ariel Model C - 06/30/17 7:26 pm

I would agree there are newer much more grippy tyre designs with softer rubber and usually thinner treads and that the SM rear is dated. The tread looks a bit square but is of a different construction to later stuff. Following a bike cornering under power and on its footrests with CORRECTLY pressured tyres, the deep tyre walls can be seen to flex and allow the tread to spread out. I think the bad name is from when 30/40 year old tyres (which often look fine) are pressed into action or are fitted to bikes with greater bhp than the design was made for.The tyre is very tough and can survive much abuse and does not puncture easily. Not used the combination you suggest.The smaller tube usually stretches to fit both sizes ,don't think it works the other way round.
Posted By: gavin eisler

Re: Technical questions: 1928 Ariel Model C - 06/30/17 9:35 pm

I know riding gear is a very personal issue, but I will chuck in my tuppence worth if it helps out MM in some way.
Riding around in Scotland means an inevitable soaking, what sort of works for me is leather bottoms , textile suit top, armour at knees and elbows. The knee armour helps stop the wind getting through and its useful for paying roadside penance, The leather trouser bottoms get a rub with Neats foot oil now and again, thus treated they will shrug off a small shower , but when the heavens open up I get out the one piece rain suit, suitably oversized to make it easy to climb into, you still get wet, but mostly from body vapor condensation, I pack a spare pair of gloves so I can put a dry pair on when the first get soaked, i have tried waxed cotton over mitts for hellish weather but found them too cumbersome.

I can recommend Forma boots as waterproof warm and comfortable, next best thing to wellies in the rain. No zips or squeaks and do a good job of damping out vibration.

When it gets hot, its silk boxers and leather bottoms, textile top with liner removed and pockets open for ventilation, a helmet with vents also helps.
For a multi thousand mile run you must be comfortable, I use raw sheepskin with the wool on as a saddle sore prevention, 1/2 a hide thrown over the seat will give you an authentic rufty tufty look, you will look stupid with this at first but a day later you will be feeling pretty smug.
This has also been backed up with roll mat foam for further arse bone comfort , usually around the 800 mile mark. most camping stores stock these so comfort should be available en route.

Take a few pairs of cyclist shorts with you , the ones with gel for the arse bones, also the thin merino tops which cyclist favour are very low bulk high comfort if you need an extra layer.

At some point you will end up hating the riding position, or maybe not , maybe it fits perfectly, but any way of stretching knees out safely should be considered, leaving the pillion footrests fitted gives a welcome change of position on some bikes.
I would also seriously consider in helmet entertainment , I find long straight roads tedious and get bad earworm.

Sounds like you are getting the beast licked into shape , more power to your elbow.
Again probably teaching granny to suck eggs here,so apologies if you already know, when repacking bearings with grease they should not be filled full,, 2/3rds is correct , more causes overheating and grease spew.

i like your choice of rubber, as far as I am concerned SM rears are only really meant for sidecars, the road rider rear should be fun in the twisties, getting the pressure right will be interesting, the original numbers wont work with new tyres, my BSA used to be 18 f and 22 psi R. now 26 front and 32 rear with modern rubber, approx 50 % higher than the book.
Posted By: kevin roberts

Re: Technical questions: 1928 Ariel Model C - 06/30/17 11:06 pm

riding gear? go with the classic look . . .

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Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 07/01/17 4:26 am

Hi,

Originally Posted by kommando
Rear SM is designed for long life,

Originally Posted by Tridentman
Named Skidmaster with good reason

Originally Posted by norton bob
I would agree there are newer much more grippy tyre designs with softer rubber

SM rear (or Speedmaster front) would not be my choice either, but none of us are planning US coast-to-coast in a fortnight, without any time to go hunting a new tyre if one wears out quicker than hoped. Plus one of MM's stipulations/observations was, "I want ones that will have a safe amount of tread left at the end of ~4000 miles of mostly-straight riding and moderate speeds through curves. Not that it ever rains in Oregon, but in case it does, having tread is far more important that period-correct appearance or the brand on the sidewall."

True, a 90-year-old bike won't produce tyre-shredding power but, as I experienced only recently, just rolling along and only braking can also wear a tyre faster than hoped. frown

If not SM, Dunlop K70?

Regards,
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 07/01/17 3:45 pm

Originally Posted by Richard Kal
I replaced each metal retainer with a 1 3/4" x 1 1/4" x 1/4" lip seal, and made a thin wall bush (light interference fit) of 1 1/4" OD, to press on the bearing boss.
That's an excellent suggestion. Thanks! Looking at the hub in light of your post it is clear what to do to implement this improvement. The seals are now on order but won't be here until Wednesday because of the 4th of July holiday. But, there's no shortage of things to do on the Ariel so it won't cause a delay.

Originally Posted by Richard Kal
To improve the braking, I shrunk a thin cast iron liner into the front brake drum (and pinned it), and modified / machined a cast iron drum off an old Norton, to duplicate the rear drum (with 47T sprocket).
On the subject of brakes, the Ariel is only 300 lbs. so even after adding a fully-equipped rider it means its brakes only have to stop 85% of a Gold Star's laden weight. Since the shoes are 7/8" wide x 7" dia. vs. the 1-1/8" x 8" of a Gold Star they should have ~70% the braking power for the same force on the brake lever, all else being equal. Given the "Stopping Factor" of 70%/85% = ~0.8 the brakes should be reasonably good if they have proper linings and unglazed drums. Unless the coefficient of friction of the drum is significantly worse than that of a Gold Star's, that is. However, you seem to imply that the material Ariel used for the drums doesn't work very well. Did you try modern brake linings before you decided to make your brake drum modifications?

Originally Posted by gavin eisler
I will chuck in my tuppence worth if it helps out MM in some way.
Believe me, suggestions like the ones in your post are greatly appreciated and have been added to an ever-growing list in my shop manual. I'll be concentrating on the bike for some months but, when I start to see the light at the end of that tunnel, that list of suggestions like yours will be organized, consolidated, and make their way to my Amazon.com shopping cart.

Originally Posted by Stuart
According to Avon's figures, the Roadrider is around 1/2" wider overall than the SM, and British bike makers weren't generous with space between tyres and non-rotating parts
Thank you very much for saving me from possibly making an expensive mistake. But damn you for forcing me to spend more time actually thinking about this in order to know what I'm doing instead of acting on impulse.

Unfortunately, since tenths of an inch could matter, and I didn't take careful measurements of the minimum gap with the current Barum 3.50-19 tire, I had to wrestle it back into place. Until I did that all I knew for sure is that tire is 3.35" at the widest and doesn't rub. However, once back in place I measured a minimum of 0.8" on either side so a tire could be a wide as 3.35+1.6= 4.9" and still spin under the mudguard without rubbing. Unfortunately, getting it under the mudguard becomes rapidly more difficult as the tire width goes up so narrower is better for fixing flats on the road.

If I stick with Avon, in contention are the Roadrider Universal (the front/rear location-specific Roadrider isn't made in 19") and the SM (kommando's, TM's, norton bob's and Stuart's cautions duly noted). If I move to Dunlop there's the K70 in a classic tread plus whatever of their modern tires are equivalent to the Roadrider.

The Roadrider Universal is available as a 3.25-19 which Avon says is 3.9" wide, and as a 100/90-19 they say is 4.3" wide. However, I have a 100/90-19 Roadrider on the back of my BB Gold Star and it measures 4.1" (on a WM2 rim, the same as the Ariel's) so I can't count on Avon's measurements precisely matching mine.

As for the SM, Avon's site says "Modern rubber compounds deliver enhanced durability and performance." Unfortunately, in this context "performance" probably means longevity not traction (further, it is only S speed rated at 112 mph so I would have to watch the Ariel's throttle carefully...). But, to list what I found, Avon gives 3.7" as the width of a 3.50-19 SM, which is 0.2" narrower than a 3.25-19 Roadrider. However, this isn't necessarily inconsistent since the 3.50 SM has a larger diameter (771.2 revs/mile) than the 3.25 Roadrider (797.9 revs/mile) so the aspect ratio is different.

The Dunlop K70 in 3.50-19 is listed as 3.78" wide, approximately the same as the Avon SM in the same size.

Anyway, my measurements show that all of the above tires would fit. However, the SM is eliminated because of the anti-recommendations, and I'd have to think more about it to consider the K70 and other Dunlops, so it comes down to deciding between the two sizes of the Roadrider at either 3.9" (Avon's claim) or 4.1" (my measurement) wide. Again, while wider might be better on the road, it's worse if there's a flat because of the increased difficulty in getting it out from under the mudguard.

Given a modern tread pattern on the back there's no reason to have a classic pattern on the front so a 3.25 Roadrider up front seems best.

Since I still needed to true the rim and turn the drum it wouldn't hold up anything to sit on this decision for another day or two to give time for opinions to pour in. That said, there's a lot to be said for crossing things off my very long to-do list. So, while taking a break for lunch yesterday I placed an order for a 3.25 Roadrider for the front, a 100/90 Roadrider for the rear, and three Michelin tubes.

If on-line reviews of these tires are anywhere close to correct, half the tread should still be on them at the end of 4000 miles. However, I have a year to decide if I should bring a spare anyway. Luckily, a 3.25 could be used on the back as well as on the front, so maybe having just one such spare would be adequately over-cautious.

After getting the tires ordered I, ahem, turned to the rear drum. After having devised two complicated ways of turning it I tried something simple first, since I always could make it complicated if necessary. The rear axle has a flat at one end to aid in tightening the various nuts and tensioning the bearings so I used that to clamp the wheel, complete with tire, in the vise on my mill. I have the mill itself adjusted to be accurately horizontal which, unlike a lathe, isn't something usually needed on a mill. But, for a job like this it speeded things up. Any way, after mounting the wheel and adjusting it to be precisely horizontal I rotated it slowly by hand and used the sides of a 5/8" carbide end mill to skim the surface. I took a number of light passes until at 0.008" the drum was round.

Given the ~14" lever arm of the tire a 9/16" axle bends by a few thou. with fairly small up/down pressure on the tire when turning it which, if the pressure were uniform for an entire rotation, would result in the drum being a cone (albeit, with the outer edge only a few thou. larger dia. than the inner). However, by being conscious of this as well as applying the turning motion with my hands at 90-deg. to the mill this "coning" effect was negligible (to try to be clearer, if the carbide mill was at x=0, y=3.5" and my hands were at x=+/-14", y=0")

Finally, I measured the dia. of the drum to be 7.034" which is a number Vintage Brake will use to arc the new shoes later this summer. At that point the rear brake should work as well as its design limitations allow.



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Posted By: Stuart

Re: Technical questions: 1928 Ariel Model C - 07/01/17 5:15 pm

Hi,

Originally Posted by Magnetoman
The Roadrider Universal is available as a 3.25-19 which Avon says is 3.9" wide, and as a 100/90-19 they say is 4.3" wide. However, I have a 100/90-19 Roadrider on the back of my BB Gold Star and it measures 4.1" (on a WM2 rim, the same as the Ariel's)

Yes ... my information from Avon is the "width" and "dia" should be the measurements on the "rec rim" - WM4 equivalent for a 100/90, WM3-equivalent for the 3.25-19 Roadrider and 3.50-19 SM.

Hth.

Regards,
Posted By: Shane in Oz

Re: Technical questions: 1928 Ariel Model C - 07/01/17 9:58 pm

Originally Posted by Magnetoman
Given a modern tread pattern on the back there's no reason to have a classic pattern on the front so a 3.25 Roadrider up front seems best.

I have been told that girder forked machines steer much better with ribbed front tyres, but don't have any direct experience.
Posted By: franko

Re: Technical questions: 1928 Ariel Model C - 07/02/17 2:34 am

I haven't any experience with them, but they might have a style of tire you are looking for.
https://www.cokertire.com/tires/styles/motorcycle-bike.html#shop_size_motorcycle=11171
Has anyone used their product and have an opinion?
Posted By: gavin eisler

Re: Technical questions: 1928 Ariel Model C - 07/02/17 2:00 pm

You may find that a deflated tyre fits under the mudguard.
I carry one of these CO2 tyre inflators and a couple of spare cartridges for times when no pump is available.
https://www.tyreinflators.co.uk/
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 07/02/17 4:43 pm

Originally Posted by Shane in Oz
I have been told that girder forked machines steer much better with ribbed front tyres,
Originally Posted by franko
I haven't any experience with them, but they might have a style of tire you are looking for.
Thanks for the recommendations, but that ship has sailed:
Originally Posted by Magnetoman
while taking a break for lunch yesterday I placed an order for a 3.25 Roadrider for the front, a 100/90 Roadrider for the rear, and three Michelin tubes.

Originally Posted by gavin eisler
I carry one of these CO2 tyre inflators and a couple of spare cartridges
I carry those CO2 inflators in the kits of my modern bikes (they have much smaller kits because there's much less that can be done), but only because the tires are so huge that using a hand pump would be out of the question. For a smaller tire they're also certainly much more convenient but if anything goes wrong, or you and your riding companions suffer more than one flat, you only have a couple of chances to fill the tire before you're out of CO2. For that reason I prefer a small double-acting bicycle pump.

I continue to make progress. What was until very recently a complete, running motorcycle is now in an ever-increasing number of pieces around the garage...

I remembered to find a BSA side stand in my hoard of parts to place near the machine as a reminder to fabricate a bracket to attach it. I'm sure that more than once on the ride I'll be grateful I have a sidestand rather than always having to wrestle it up onto its rear stand even for brief stops.

The rear of the bike is on its rear stand so I jacked the front up to remove that wheel as well in order to turn its drum the same way I had done the rear drum. The front drum required me to skim 5 thou. to get it round. It had been gouged by a rivet sometime in the past but I stopped removing metal when the drum was round leaving a residual trace of the gouge around ~1/3 of the circumference. I'd rather leave the extra metal everywhere else than make the last traces of the gouge disappear since it represents only a tiny fraction of the surface area. Its final diameter ended up only 0.002" from that of the rear drum, i.e. 7.036".

After truing the front drum I removed the tires from both. Doing so reminded me -- twice -- why I hate changing tires. I'm definitely going to upgrade my kit for this trip from the pair of 8-1/2" tire irons that fit in my normal toolbag, but mostly I'm going to pray that I don't get a flat.

I admit in the back of my mind I was considering the possibility of using one of the current tires as a backup on the rally since they have all their tread and are "only" ten years old. But, I checked the DOT codes again against what they should look like and found they weren't made in 2007. They were made in 1997.

I use the same jig for truing rims as for balancing them, but the Ariel's wheel was too wide to fit in it so I had to pause to make a 1.5" spacer for the jig. However, when I finally got the wheel on the jig I didn't even bother measuring the wobble or the out-of-round because both were negligible (no more than 1/16"). The same was the case for the front wheel. I only checked the torque on a couple of random spokes but they were ~40-50 in.lbs. as my research said they should be. I'll 'ping' all of them to make sure there are no outliers but all indications are that whoever built those wheels did a good job (although he installed crappy tires).

I can't balance the wheels until the new tires arrive next week so the bike is suspended above the lift by the rear stand in the back and a 2x4 and 4x4 near the front of the engine. Since the girder is now free of its wheel that's probably going to be next.

There's play in the steering head so the builder didn't do as good a job with it as he did truing the wheels. Also, the front axle doesn't turn freely so I'll have to research in my bearing manuals the correct torque for the nuts. Once the forks are done all that will remain is the engine. And gearbox. And clutch. And magneto ...

Obviously, my original plan to put quite a few miles on it before beginning the restoration has fallen apart. As some general once said, "No battle plan survives contact with the enemy." It makes no sense to reinstall the wheels, then tear them apart again in six weeks when Vintage Brake is ready for the backing plates. And, the weather is too hot to ride other than very early in the morning. Anyway, I'm already up to my knees in quicksand so it's too late to turn back now.


Attached picture IMG_5411.JPG
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 07/03/17 4:39 pm

The deconstruction continues. Yesterday I stripped everything off the forks, but stopped before trying to disassemble it. Given the number of cables I'll probably never get them properly routed and hooked up to the correct levers again. The reason I paused at this point was because springs can store some serious energy, and the one in these forks is big enough to merit contemplation before trying to remove it. So, last night I read all the material I'd collected in the 'forks' chapter of my shop manual. Although none of it deals specifically with the spring in 1928 Ariel forks I now have a plan to safely remove it. However, if there aren't any posts after this one, my plan didn't work and my body is impaled on the garage ceiling...

I looked up the proper tension for the wheel bearings. Timken says no special tools are required for this "but assembler's skill and judgment are necessary." The ideal float/preload for a taper roller bearing is 0" +/-0.002", achieved by tightening the nut until "a slight bind is felt," and then backing it off by the necessary amount. Since the axles are 20 tpi this means backing the nut off by 1/4 of a flat.

Yesterday I also placed a ~$100 order for mostly tire-related items including upgraded tire changing tools to have on hand when the new tires arrive, as well as to have along for the ride. The pair of 8-1/2" levers I have in my normal toolbag certainly have earned their keep over the years but the 11" levers I ordered will make the work that much easier. Although they won't fit in the toolbag they will in the panniers that I'll be adding. Also, I used the opportunity to buy another pair of 8-1/2" levers to split between my toolbags here and in Ireland so I'll have three in each. Having a third lever is something I've wished for when changing tires, but then forgotten to do anything about. This time I remembered.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 07/04/17 4:46 pm

My worry about the spring turned out to be unwarranted. I devised a spring compressor from scrap steel that happened to have holes in just the right places and two lengths of all-thread but as soon as I started compressing the spring the fork legs started rising. This told me the spring isn't under compression when the wheel is off the ground (or is missing). I then removed the forks, losing only four of the 1/4" balls in doing so, and put it on a surface plate to check for bends or twists. Everything checked out so I didn't have to deal with bending anything back into shape. Also, the races are in excellent condition.

I took a lot of photos to make sure I would be able to see where every nut and washer went if I forgot, marked the L and R legs and lower link with tape, and then proceeded to disassemble the spindles individually, clean them and their bores, lubricate, and reassemble. One spindle had a small amount of galling on a small portion that I dealt with using a jeweler's file. Nothing was bent or out of spec (assuming I actually had specs to check them against) so I reassembled each link and checked that it rotated smoothly through its entire range before moving on to the next one.

As for what constitutes out of spec I consulted 'The World's Best 1928 Black Ariel Shop Manual' (TM pending), which has grown to ~560 pages. The way the spindles are made it is possible to fully tighten them and thus lock the link solid, which clearly isn't desired. Here none other than Roy Bacon has the answer: "fork-link adjustment will be correct when [the thrust washers] have no side-play, but at least one on each spindle can still be turned." This is consistent with the few other recommendations that basically say to tighten until stiffness is felt and then back off a little.

No one gives a numerical spec for the fit of the spindles in their bushings, instead mentioning a "sliding" or "running" fit, not a "rattling" fit. While the terms "sliding" and "running" are used by machinists to describe different classes of fit the descriptions in my 'shop manual' were not written by or for machinists. Anyway, all spindles fit nicely in the bushings without play when dry and turn smoothly without binding with my choice of Mobilgrease XHP222.

On the subject of spindles, their ODs are not Imperial. Two of them measure a bit over 0.506", another is a bit over 0.520", and I forgot to measure the fourth before I installed it. These dimensions don't correspond to any reasonable fraction in the Imperial world. While a spindle could be easily turned to any desired diameter to match a hole, a bushing has to be sized using either a reamer or a boring head. The former is (relatively) cheap, easy and accurate, but is limited to the reamer sizes available. A 12.9 mm reamer would make a hole 0.5079", from which we can safely infer that's what was used when reconditioning these links for the 0.506" spindles. The bushes for the 0.520" spindle would have been sized using a 13.3 mm reamer (0.5236"). From this I suspect the original spindles started life at 9/16" (0.563") but I can't find that information.

Update: I've been told that the original spindles were 1/2". If this information is correct it means the ones currently in the bike are replacements, not originals that were modified. They are fairly complex (hex head, shaft with two grooves for grease, threads, and reduced diameter tip with hole for cotter pin) so the four of them took a fair amount of time to machine from scratch. Or, perhaps(?) they started life as 9/16" spindles that were modified by machining, which still would have taken some time.

In both cases the bushes would be 0.0015-0.002" larger than the spindles (which I measured with a micrometer and have rounded off the readings here). According to Machinery's Handbook, for a 1/2" shaft this clearance corresponds to a class of fit of RC4, RC5 or RC6:

RC4 (clearance 0.5-2.0 thou.). Close Running Fit. Intended for moderate journal pressures and where accurate play and minimum play is desired.

RC5 (clearance 1.2-2.9 thou.) and RC6 (clearance 1.2-3.8 thou.): Medium Running Fits. Intended for higher running speeds or heavy journal pressures, or both.

As can be seen from how he correctly sized the spindles and bushes for the intended use, whoever rebuilt the forks did a very good job on most aspects. However, a few things definitely needed attention so it's good I took them apart. It also gave me a practical understanding of how the various components of this fork interact, which can only come from hands-on experience.

The former rebuilder left paint on the surfaces for the three dampers (i.e. steering damper plus two for the up-down motion), some of which had worn away by the friction. However, the slick paint largely negated the action of the friction surfaces so I scraped most of it away and then eliminated the rest with a Scotchbrite pad on a die grinder.

When the bike had been together I was puzzled by how the steering damper worked, or didn't work, because when the knob was fully tight there still was daylight between the friction material and the clamping surfaces. When I had it apart I found the reason. I can't easily describe it, but there's a home-made piece of brass ("trunnion" in the Ariel parts manual) at the end of the damper rod ("tie rod") that is constrained from turning by the fact a spindle passes through a slot in it. Anyway, the diameter was slightly too large for the ID of the steering tube so it jammed before pulling up tight enough to compress the friction material. Part of the reason was the inside of the steering tube was rusted and had collected junk at the bottom, reducing the effective ID. I turned the brass piece down by ~0.01" and it now works great. I also polished the inside of the steering tube as well as the damper rod also was quite rusted.

I couldn't find my stock of cotter pins for the ends of the spindles so I ordered a batch from Amazon.com for delivery Wednesday hoping that would cause the hidden pins to reveal themselves, but that plan hasn't worked as yet. I also ordered a batch of 1/4" balls to replace the ones I dropped on the floor and to give me some extras to drop as well. I did this even though I probably have extra ones with my BSA parts, but had I not ordered them I'm sure I would have regretted it. I can't finish assembling the forks until those items arrive. However, that will give me time to think about a design "feature" that doesn't provide anything to stop grease pumped into the zerk on the lower link from finding its way out by getting onto the friction disks for up-down damping. I'll see if a modification involving an O-ring or two might solve this.

Although it needs the cotter pins as insurance the forks are together and adjusted right now. They are very smooth, much smoother than when I started, and I discovered and dealt with several issues that would have caused functional issues, so I'm really happy with how they turned out. They now should again work as good (or bad) as they did the day they left the factory.

As far as documentation goes, this is a Star Trek rebuild ("boldly going where no man has gone before."). The lack of technical information is actually making this rebuild more enjoyable. Thus far, at least. Being forced to research runout specs for bearings used in similar applications, determine appropriate modern lubricants, rebuild my first-ever girder fork without even an exploded diagram as a guide, etc. all are making this an interesting journey. For me, that is, and thus far, at least...


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Posted By: No Name Man

Re: Technical questions: 1928 Ariel Model C - 07/05/17 1:57 pm

Interesting for us as well...pardon my speaking for others. I am really enjoying your account.

Bill E
Posted By: Alan_nc

Re: Technical questions: 1928 Ariel Model C - 07/05/17 5:22 pm

I agree.....I read every one of the posts. Wish I could go on the ride.
Posted By: Magnetoman

Re: Technical questions: 1928 Ariel Model C - 07/06/17 2:27 am

Originally Posted by No Name Man
Interesting for us as well...
Originally Posted by Alan_nc
I agree...
Thanks, guys. As long as people are reading it, I'll keep posting.

It's almost certainly too optimistic, but still not completely hopeless, to have the Ariel ready by October. If that happens I'll use it on a ~1000-mile "singles" ride through West Texas which, if nothing else, will tell me how ill-prepared the bike and I are for the Cannonball. Accompanying me on this ride will be the guy who got me into this Cannonball mess in the first place, but who later partially acquitted himself by selling me the Ariel, but who I'm sure I'll curse many times before the Cannonball is over. Present plans are to use two of my Gold Stars for the ride. If by some miracle I get the Ariel ready in time I'll still bring one of the Gold Stars as backup (our group will be followed by a breakdown truck for the week).

I made several small steps forward since my last post:

I had started thinking of appropriate panniers for the ride, to carry wet-weather gear, industrial strength tire changing tools, etc. I'd spent some time searching the web and had found some black faux leather bags that looked like they would do. However, I then remembered the Chase-Harper saddlebags I bought years ago to use with my Trident that were stored on a top shelf in the garage. They've probably upgraded the design in the ~20 years since I bought them (their current CHR Sport Tour seems equivalent) but the ones I have are perfect for my needs so that's now crossed off the list.

I found the "missing" stock of cotter pins but couldn't find any 1/4" balls so reinstalling the forks couldn't happen until after they arrived today. Or until after I magnaflux them (see below).

I packaged the brake backing plates and shipped them to Vintage Brake. I insured them for $1000 but god help me if they get lost in transit either way because replacement brakes for 1928 Ariels don't exactly grow on trees. My note to him requests he reline them using the material he feels has the best first stop capability in wet or dry, with fade resistance of much less concern. I won't be racing anyone, and even coming down on the other side of the Rockies I'll have 500 cc of compression to help keep things in check, so I'm not too worried about brake fade.

Unlike on our "modern" bikes the axles stay with the wheels. Since this means the axle would be buried in dirt or asphalt when changing a tire I drilled a hole in a short piece of 4x4 to use to keep that from happening.

The 4x4, like many other things, is something I wouldn't necessarily remember when packing a year from now so all such "special tools" go on a shelf. Where I use something other than a "common" tool, but I don't want to put it on that shelf just yet, I make a note of the tool on a list I keep on the shelf. For example, if play develops in the headstock I'll need a rather large 3/4W spanner. The wheels need large but thin open end spanners to adjust the preload (1/2W for the front wheel and 9/16W for the rear). I wouldn't want to forget to pack them, but all of them are larger and heavier than the "usual" range of spanners so I wouldn't want to bring any additional extra-large, extra-heavy spanners in sizes that aren't needed.

It might seem I'm obsessed with changing flat tires, if only because I am obsessed, but I ordered a few more tire-changing tools.

I used a gauge to determine the sprocket I installed on the rear wheel to drive a speedometer is Module 9, 14-1/2 deg. pressure angle. I made a note of this in case I need to buy a cutter to fabricate a different driven gear to match the ratio of whatever speedometer I end up using.

The previous rebuilder had a rather crude home-made piece at the bottom of the steering damper mechanism so I fabricated a nicer hand-made replacement

Finally, off-line my Aussie conscience pointed out that it's not unknown for girder fork tubes to crack at the lugs, suggesting I consider having them magnafluxed. Given that Ariel's 1927 frames cracked it's not like I hadn't thought about this. However, the relevant information to weigh includes:

-- all the tubes enter their lugs straight on, except for the bottom tubes at the lower link, which are bent where they enter the lugs thus spreading out the stress (although he then pointed out that under braking or hitting potholes there is some amount of bending stress where it enters the lug so it's still an area of increased stress).

-- closely inspecting the paint at the lugs under magnification shows no sign of any crack.

-- there was rust inside the steering tube, which is a concern since that means the lugs or tubes could have rusted to some unknown extent had portions of them been paintless over the past 90 years. But, other than that, I found no signs of rust damage anywhere else (recognizing that thick primer and paint could disguise it).

-- although cracking of the 1927 frames is mentioned in by various writers nowhere did I find any comments about defects in their girders.

None of the above is nearly as definitive as magnafluxing, of course but, as I wrote my Aussie friend yesterday, it was enough for me to roll the dice on the forks as-is.

However, since writing that yesterday I realized I could easily magnaflux them myself using the magnet I built for remagnetizing magnetos, and without disassembling them, as long as I was willing to sacrifice the paint around the lugs (which I am). I already have fluorescent penetrant that is supposed to be good for this absent a magnetic field, but I ordered two types of magnetic powder.



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Posted By: Lannis

Re: Technical questions: 1928 Ariel Model C - 07/07/17 2:30 am

I'm reading it all, too, very interesting it is .... Been meaning to ask, since you're concerned about changing flat tires, whether you'd consider putting "Slime" in the tubes? Stuff's very effective; it's a mess in a tubeless tire, but there's no downside in a tubed tire, it'll cut your chances of a tire deflation due to a puncture down to almost nothing. Of course, if you cut one wide open on a piece of quartz or a metal strip in the road, it won't help, but it'll keep a piece of wire or a drywall screw (and I'll bet there are 10 million drywall screws, fallen off of construction trucks, on the highways of the US) from stopping you out on the road. You'd be able to examine your tires at night and spot the bright green goo surrounding the offending bit of metal ....

Lannis
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/07/17 6:16 pm

-- I slightly altered the title of the thread to better reflect its current content --

Originally Posted by Lannis
I'm reading it all, too, very interesting it is .... whether you'd consider putting "Slime" in the tubes?
Thanks for your comment. As for Slime, the experiences I had have left me with a bad impression of tire sealants. As you said, it's a real mess in tubeless tires. A nail in a tubeless tire usually causes it to deflate slowly, and perhaps a sealant might causes it to deflate even slower. But, that just means a little longer before you notice the problem and have to take the tire in for repair. At which point the shop will yell at you for making it a mess for them to repair, plus it will have destroyed the expensive pressure sensor as well. The one time I was asked to fix a flat in a motorcycle tube that had sealant in it the stuff had made such a mess of the outside of the tube that I couldn't clean it properly to patch it. Other people may have had better experiences with the stuff than me but I don't use it.

If anyone is interested, the tire tools in my Moose 'Rear Fender Pack" tool kits here and in Ireland are:

(3) 8-1/2" Motion Pro tire irons (previously two ea. but I've now added a third)
Patch kit: grit cloth, (4) packets alcohol wipes, 1.5 mL vial isopropyl, glue, large patches, stitcher, and glue
Key for unscrewing valve inserts & tap/die for fixing threads
(4) Schraeder valve inserts
Blackburn 'Shorty' tire pump
Pencil-type tire pressure gauge

This kit has served me well, allowing me to repair at least four punctures that I can recall over the past 15 years. I replace the glue and alcohol wipes annually as a precaution since even a tiny hole would allow them to slowly dry out and there's no real way to check for that without opening them. I use the alcohol to make the area on the tube surgically clean prior to applying the glue and patch. Personal experience and observation of failed repairs made by others tells me this is an essential step in making a repair that is permanent.

I'll have the above kit on the bike on the Cannonball but will add to the panniers:

Spare Michelin tube that fits both tires
2x4 wood block with hole for axle
11" Motion Pro tire tire iron
Motion Pro 'Bead Pro' bead breaker 2-piece set, 16"
(4) Motion Pro 'Bead Buddy II"
Small container of tire mounting paste with brush
SKS 'Airbuster' CO2 filler
(5) 25 g CO2 cartridges

In an earlier post I said I don't use CO2 cartridges in my toolkit (although I do have them in the much smaller tubeless kits of my modern bikes), but since I'll have space in the panniers I spent a half-hour researching units before settling on the SKS 'Airbuster'. I found that although most such units get mostly-high ratings, their negative ratings almost always say the pin for puncturing the cartridges failed after a few uses. That eliminates any such unit from consideration since there's no point having a tool if it can't be relied on to work when it's needed. As an aside, it's interesting how many 5 star ratings of various units were followed by the comment that they hadn't actually used the item yet but it looks like it should work great.

The above will give me a total of six tire irons which I recognize is excessive but, hey, nothing exceeds like excess. But, that's not all. I also ordered a 'Baja No Pinch Tire Tool' that hasn't arrived yet. I'll have to modify its mounting system to work with the Ariel's axles but if it does work as it appears to it will be along as well. Of course, fingers crossed, I very much hope that none of it these tire tools will be needed.

While it might seem I've lost the plot with tire tools (and maybe I have...), there's a reason for it. Repairing a flat on the side of the road is the most tiring job I'm likely to encounter en route from one stop to the next so, if it happens, anything that makes it faster, easier, and less prone to error (i.e. pinching the tube) is well worth it to me.

Thanks to all the orders I placed over the past few days activity suddenly picked up in the Receiving Department. The major delivery yesterday included the two tires, but the tubes aren't due until later today.

After I mount the tires and balance the wheels, and since I can't magnaflux the forks until early next week when the magnetic powder arrives, I'll probably wire the bike next. I'll leave extra lengths of the negative, earth, and taillight wires dangling at the front to be ready to attach inside the headlamp bucket when the forks are back on. I'll use the same circuit diagram with NiMH batteries -- the Ariel has a magneto, not a magdyno -- that was in my 'rewiring' thread in the 'projects' forum until Photobucket ate it.
Posted By: Tridentman

Re: 1928 Ariel Model C - 07/07/17 7:08 pm

My mobile puncture repair kit is remarkably similar to yours, MMan---except for less tire irons---I find it much easier to use three than two as you have observed.
The only thing I have in my kit in addition to the items in yours is a small tin of Johnsons Baby Powder.
After the puncture has been repaired and the adhesive set I sprinkle a little powder over the repaired area --this prevents the possibility of a small spot of adhesive bonding to the inside of the tire and potentially tearing away the patch due to movement between the tube and tire.
An old tip given to me by my motorcycling mentor in the 1960s.
Does it work?--well--I have never had a repeat puncture at the site of a patch.
Would I have done if I had not used powder? Don't know but I guess that is what is called insurance.
Just a thought.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/07/17 7:47 pm

Originally Posted by Tridentman
a small tin of Johnsons Baby Powder.
I install new tubes with baby powder to minimize abrasion, but rub the excess glue at a patch with dirt (which isn't always available), so that's an excellent suggestion. A 1 oz. travel size container of baby powder now will join my supplemental Cannonball kit.

A decade ago Mike Jackson (of NVT) had a flat at the Irish Rally. I repaired it for him using my surgical procedure, which he thought "interesting" because he said he'd never seen anyone take so much care, but which held through the end of the rally. I assumed Mike thought my procedure was overkill but he was just being nice because I was doing him a favor. The next morning the then-writer of the workshop column in Classic Bike commented in passing that modern tubes used a different rubber to which patches didn't stick very well. Although he was wrong, I thought he had said this because he had seen me repairing the tube in the parking lot. However, later that day I learned he had patched Jackson's tube twice the previous day but both of his patches had failed. Mike hadn't outed him to me for his bad patches.
Posted By: Stuart

Re: 1928 Ariel Model C - 07/08/17 3:28 am

Hi,

Originally Posted by Magnetoman
As for Slime, the experiences I had have left me with a bad impression of tire sealants.

+1. When my first T160 was new, I put Slime or something similar in the tubes. No punctures and, apart from being cussed by tyre fitters who'd tried to balance the wheels, no problems.

Two years later, I moved to London to make my fortune as a dispatch rider. I put tyre sealant in the tyres of my work bike. London roads probably have as much variety of debris as US roads, just concentrated into a smaller area. I can honestly say that, in nine years of dispatching and commuting in London on that bike, I never got a puncture from "a piece of wire or a drywall screw", but plenty from other debris that let the sealant out of the tube into the tyre. frown After having to replace a couple of otherwise perfectly-good tyres because they were contaminated with sealant, I stopped putting it in the tubes because it was costing more than it was saving.

Three years ago, bought a car that has a bottle of sealant instead of a spare wheel/tyre. First puncture (in a ****** snowstorm with son-'n'-heir waiting after being dropped off by the school bus facepalm ), I put the sealant into the tyre. About as much use as a chocolate fireguard. Drove the car slowly to the nearest garage (less than two miles away). Garage couldn't fix the puncture 'cos the tyre was contaminated with sealant. Taxi ride home, new tyre. mad Now I just have breakdown insurance that includes transporting the car with a puncture to the nearest garage that can fix it. cool

Curiously, the weirdest non-puncture I had working in London was a six-inch nail into the rear tread and out through the sidewall, but missed the tube. crazy

Originally Posted by Tridentman
The only thing I have in my kit in addition to the items in yours is a small tin of Johnsons Baby Powder.
After the puncture has been repaired and the adhesive set I sprinkle a little powder over the repaired area --this prevents the possibility of a small spot of adhesive bonding to the inside of the tire and potentially tearing away the patch due to movement between the tube and tire.

When I was youthfully-limited to pushbikes, I remember puncture repair kits containing "French chalk" for that; the last such kit I bought for fixing the kids' pushbikes has a lump of chalk and a minature grater ...

Mind, the baby powder will probably better soothe those ... uh ... tender areas after many days riding ... than "French chalk" ,,. whistle

Regards,
Posted By: kevin roberts

Re: 1928 Ariel Model C - 07/09/17 12:10 am

has anybody suggested taking one of these along?

[Linked Image]

these cheap little magnetic parts trays have become essential to me. i buy the little tiny ones and clip them to whatever i'm working on to hold the nuts and bolts. i have lots of them, stuck to toolboxes, to machines i'm working with slowly, and even holding the fasteners for assemblies i've taken apart and chucked into a not-now box.

if you're going to be messing with this old machine in inconvenient places, one or two of these just stuck to the metal somewhere on the bike will help keep you from losing some irreplaceable CEI screw into the weeds.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/09/17 12:55 am

Originally Posted by kevin roberts
these cheap little magnetic parts trays
That's a very good suggestion. Thanks.

I didn't have much time yesterday, and much of it was spent consolidating my gains (organizing the new items that had arrived, cleaning up work spaces, putting away tools, updating lists in my shop manual, etc.). In case it's not obvious, I'm approaching this project methodically and documentation is an essential part of it. Viewed as an R&D project, while rebuilding the Ariel certainly is a major part of the project, the actual "deliverable" is a running bike that rides into Portland, OR a little over a year from now. A methodical approach maximizes the chances that will happen with a minimum of drama along the way ("Damn, if only I had remembered to bring that spanner for the headstock...").

The tubes didn't arrive as I had expected so I checked and they're actually due on Tuesday. However, the front tire of my BB Gold Star has a very slow leak so two months ago I bought a replacement tube for it. I've been avoiding dealing with it ever since then, because I hate changing tires, so that tube along with a new rubber rim band, went in the rear wheel, but not without a fight. Which reminds me, add gloves to the list of tire tools in my previous post. I carry them in my toolkit but list them separately.

Anyway, crawling around on the floor just isn't a gentlemanly thing to do so I fabricated an Al tripod stand that supports the wheels ~14" off the ground. This makes the job much easier. All that's required is a TIG welder, He-Ar mix (because the Al pieces were too thick for Ar alone with a 200 A welder), lathe, mill with dividing head, and a good stock of raw materials. The stand is strong, light and breaks down into four pieces that fit into the length of the panniers I'll be using.

The front rim had some rusty patches in it so I hit them with a wire brush, applied an etching primer, and sprayed gloss black to provide a nicer surface for the tube to lay against. That paint will have plenty of time to dry before the tubes arrive on Tuesday.

Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/10/17 1:01 am

Someone wrote to me off line wondering why I was revealing useful information to my competition. It is interesting that at least two other Cannonball participants are on Britbike but both have been quite silent about their preparations. Perhaps they already know everything in my posts, or maybe they know it to be incorrect (in which case, I wish they would point out any errors), or maybe they are too busy to share information.

I don't look my riding in the Cannonball as a competition with anyone else. It's something I'm doing to experience for myself. I'm going to do everything I can to finish without losing any points but, again, not to "win," but to have accomplished that for myself on a bike as close to 1928 specs as is reasonable for the roads of 2018. If others in the Cannonball get something useful from what I've written, that's great. If they "beat" me because they lose fewer points thanks to something picked up from this thread, that's fine as well.

Turning back to the Ariel, when I had the rear wheel alone on the rollers a few weeks ago it was quite heavy in one location so I wasn't surprised to find the same when the tire was installed. My rollers have a sensitivity of 1.0 g-cm so at the ~20 cm radius where I attached the weights (i.e. the end of the spokes) that corresponds to being able to detect an imbalance of ~0.05 g (although I settled for getting to within 0.5 g). Luckily, I have a sheet of 1/8" Pb because it took 87.0 g (3 oz.) to balance the wheel. I wrapped two ~1"x3" lengths of the Pb around two adjacent spokes and, although I'm sure it would have held by itself, safety wired it as well.

Since I was obsessing with tires I machined a pair of extensions to clamp on the ends of the rear stand to raise the bike by 1-1/2" to make it easier to remove the wheel from under the mudguard. The tubing is oval so machining these took longer than just drilling a couple of holes.
Posted By: RPM

Re: 1928 Ariel Model C - 07/10/17 2:53 am

I think your doing a good job preparing your bike. If I can help in any way please let me know. It is a contest so the racer comes out in me and I want to win. Jack Wilson would have been disappointed if I approached any other way. Any reason to ride the Cannonball is a good reason if you ask me.
The only thing I see i would do different is I would not do is carry a tire patch kit. I would carry a spare tube and change it. Saves time if you have to repair a flat.

Started on the 1923 and 1924 Nortons
I have two sets of wheels at Buchanan's right now having spokes made and Sun Alloy rims punched to fit stock hubs. No clincher tires for us. We will lace, fit brake pulley and true them in house. Also fit modern bearings in hubs. We will run Bridgestone 21" tires front and rear.
I have both motors apart. New pistons on order. Once I get pistons and weigh them the crankshafts will go out to Alpha Bearing for rebuilding. One set cams out to Web Cams for repair. Both motors need valves, guides and springs. Need to repair a few broken fins. All in all not many surprises so far.
We are making exhaust pipes that will be quick detach to help with getting rear wheel out. Otherwise it would be a struggle to remove rear wheel with the pipe in the way.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/10/17 7:13 pm

Originally Posted by RPM
It is a contest so the racer comes out in me and I want to win.
That's perfectly understandable, and I suspected as much in your case. My professional background is different, with collaboration an essential part of the "competition." You definitely can tell the "winners" from the "losers" in my profession, but the "scoring" is quite different.

Originally Posted by RPM
The only thing I see i would do different is I would not do is carry a tire patch kit. I would carry a spare tube and change it. Saves time if you have to repair a flat.
But, what do you do if you get two flats before you get back to base? Or your tire iron slips and you puncture the new one?

My approach to tire repair was strongly affected by an experience a Britbike lurker and I had twenty years ago when we set off on a four day ride on four dual-sport bikes that Honda loaned us because of something we were involved with (come to think of it, my Cannonball partner joined us on that ride as well). Honda knew our plan was to stick to fire trails as much as possible so they supplied the bikes with full knobbies. Unfortunately, it turns out that such tires are perfectly designed for the knobs to flip nails to be vertical in order to puncture the tires between the knobs. We got a lot of practice changing tubes on that ride. A bike would wobble to a stop with a flat, one person would tilt the bike on the sidestand, another would unbolt the tire, and another would remove and replace the tube.

Anyway, we rapidly went through tubes on that ride, and only made the full planned circuit because we managed to arrange a resupply mission. My conclusion from that experience is one needs to be prepared to patch tubes and inflate them more than once (hence, a bicycle pump, not CO2, in my "permanent" tool kit). I'll have a spare tube in the panniers, but also a patch kit.
Posted By: RPM

Re: 1928 Ariel Model C - 07/11/17 1:14 pm

Changing tubes on a 18" knobby is a task for sure. Changing tubes on a 21" modern tire with sun rims is much easier. I do not use tire irons when installing tires unless it is absolutely necessary. A good rubber hammer will not pinch the tube. The first 10 years I worked at Big D we did not have a tire machine. We had a wooden box with the tire tools in it. The box was the correct size so the rim lay on box. I was taught to remove the tire with tire irons but you could only use a rubber hammer and your hands to install the tires. This works fine for most tires on vintage bikes.
I removed a tube once that had one patch on the outside of the tube and 13 on the inside where they had pinched the tube. It was holding air! I keep it hanging up in the shop for years.
Most tire trouble I saw on the trip was from using cheap tubes and Non DOT tires. We will buy the best available.
We plan to have a large support trailer with tons of spares and tools. If you need anything on the trip just ask and it is yours.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/11/17 5:46 pm

Originally Posted by RPM
I removed a tube once that had one patch on the outside of the tube and 13 on the inside where they had pinched the tube. It was holding air! I keep it hanging up in the shop for years.
A friend has a "Wall of Shame" in his shop where he places items removed from customers' bikes that are unbelievable. For example, someone came into his shop to have some non-tire work done and my friend saw the rear tire was so worn that the cord was showing in the center. When he pointed this out, the customer already was aware of it but told him he was riding leaned over to use up the remaining good part of the tire.

Originally Posted by RPM
We plan to have a large support trailer with tons of spares and tools. If you need anything on the trip just ask and it is yours.
I sincerely appreciate that offer. And I sincerely hope I won't need to take advantage of it! In the same vein, since electrical issues of one kind or another are the most common kind of failure I'll come with an extensive array of specialized diagnostic and repair tools and supplies. If you have a problem, just ask. But, with ~100 bikes potentially having electrical issues, and with electricity being such a mystery to most motorcyclists, please don't let this capability be widely known because the demand could be overwhelming, ending up with a lot of people pissed with me because I selfishly decided I needed to eat and sleep instead of helping them.

This brings another story to mind. Some years ago at the Irish Rally someone's magneto gave out with symptoms that told me it was the condenser. Since I carried the necessary tools and supplies with me I offered to fix it for him. He said he was horrible with mechanics so another guy offered to help me remove the magneto from the Triumph (which did not have the aftermarket long bolt that made removing it relatively easy). So, there we were, up to our elbows in dirt and grease in the parking lot when the guy walked out of the hotel with his girlfriend and told us he had promised to take her into town for dinner that evening, and besides he couldn't be of any help to us anyway, so thanks very much for fixing it for him. And off they went. Unbelievable.

Originally Posted by RPM
Most tire trouble I saw on the trip was from using cheap tubes and Non DOT tires. We will buy the best available.
After installing the rear tire a few days ago, and even though I was sure (or pretty sure...) I hadn't pinched the tube, I filled it to running pressure and set it aside to check to be sure. The next day it was down by 2 psi. Oh, oh. I then filled it to 50 psi to speed up the effect, but this time I put the valve cap on it. The next day it was down by only the width of the needle, which probably was just air that escaped when checking the pressure. Day 3 I reduced it to operating pressure and left the cap off. This morning it hadn't dropped.

The moral of this story is that even with a new, brand-name (Michelin) tube, you can't count on the Schrader valve core consistently sealing. And, even if it doesn't leak, each time you check the pressure or fill it the valve is moved from its seat, giving it a chance not to reseat perfectly. So, on order are a set of valve caps with rubber seals in them that will go on all my bikes to serve as a secondary seal.

Also, given the slow leak on the front tire of my BB Gold Star, for which I bought the tube a month ago that ended up being used for the Ariel, I have to wonder if the cause might be its valve core (the bike came to me with this tire/tube so I don't know its history). After I refilled the Gold Star's tire to start a test on it the valve leaked so badly I could hear it hissing(!). Bumping the valve caused the hissing to stop. So, I replaced that valve core with one from my tool kit and started a long-term test of the pressure. I also ordered a set of name-brand Schrader valve cores to replace the unknown-brand ones I carry in my tool kit. These are 10 cent items, showing that the devil truly is in the details...

A few items arrived yesterday, including the 'Baja No Pinch' tire tool. The tool comes with a 20 mm shaft that attaches with a 1.5 mm thread, designed to be dropped into a wheel where the axle normally goes. Since the Ariel's axles stay with the wheels I machined a ~1"-long hollow shaft as a replacement and drilled it to slip over the 9/16" axles. Since 9/16" =~14 mm it means the hollow shaft has substantial walls ~1/16" thick. When the tubes arrive I'll try this tool instead of tire irons to see if it makes the job easier and less prone to error. If it does, it's money well spent. If it doesn't, it's ~$100 down the, ahem, tubes.

Previously I made a portable jack to help lift the front wheel off the ground, if needed. It's similar in design to a machinist's jack, and yesterday I made an add-on extension to increase its lift.

Vintage Brake confirmed the backing plates arrived safely yesterday, and later today the tubes are due as well as the magnetic powder for magnafluxing the forks. So, progress continues.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/12/17 4:01 pm

Who you callin' a magnafluxer, buster?

The dry and aerosol magnetic powders arrived yesterday so it was time to magnaflux. I had just finished taping the tubes, leaving the castings exposed for paint removal, when I decided to see what I could see with the paint still on. I adjusted the pole pieces of my magnet to almost touch the castings, sprayed the first one with the Goodson MFA-16 magnetic fluorescent aerosol, cranked the field up to max., and then inspected the casting with a UV lamp. Damned if it didn't show features in the casting that, once I now knew where to look, could barely be seen in the paint. For example, a ~1/8" circle on the front of two of the castings showed up brilliantly.

The MFA-16 has magnetic particles in suspension in a very thin, oily liquid that allows the particles to flow along the field lines to become concentrated wherever there are discontinuities in the field caused by casting marks. Or cracks. The particles show up bright green under UV. Detection would be sensitive to smaller features without the paint, but my magnet is more powerful than the ones used commercially so the reduction in sensitivity compared with a commercial shop working on bare metal isn't much. In any case, the result was a double-plus: my magnafluxing setup works great, and there aren't any hints of cracks in the forks.

I'm glad my Aussie conscience suggested I magnaflux the forks. As a result, I now know that it is easy for me to do this test myself, and since I now have the necessary supplies there's no obstacle to doing it whenever it could be useful. If I ever want/need to magnaflux something that doesn't fit in the gap of my magnet it will be easy enough for me to wind my own portable yoke than I can power with the largest of my DC power supplies.

However, perhaps best of all, when RPM and I are side-by-side on the Cannonball Start line a year from now and he tries to psych me out by saying "If I were you, I'd be worried about a crack causing your forks to break when we throw our bikes into Turn One," I'll just yell 'magnafluxer!,' nail the throttle, and see who blinks first when we get to that turn...

I haven't figured out a solution short of machining O-ring grooves to keep grease from reaching the fork dampers. It's not like machining O-ring grooves is difficult, but they would weaken the spindle to some extent right where the shear force is maximum so I want to think about this some more before doing something irreversible. However, since the forks don't have to be off the bike to deal with that issue they are now adjusted, greased, and installed on the bike.

When I came in from the garage yesterday I'd added a very useful diagnostic tool to my arsenal, made some real progress with the Ariel, and the granddaughters had just been dropped off for dinner at their favorite Mexican restaurant followed by a sleepover. Life is good.


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Posted By: RPM

Re: 1928 Ariel Model C - 07/13/17 12:42 pm

MM, I too will be a magnafluxer. We were worried about the forks on the 1915 Norton last year. Some big bumps along the route. Going to order all the stuff from Goodson and check all the forks.

You can have the first turn. This is not a sprint race. I am happy to tuck in behind you and study your lines. Learn your strengths and weaknesses. Then make my move when you least expect it. That is if the old side valve Norton can keep up with that modern fancy Ariel.
Posted By: edunham

Re: 1928 Ariel Model C - 07/13/17 1:55 pm

I find the most important parts of my toolkit for such events (the only one remotely comparable that I do regularly is the East Coast Moto Giro), is my cell phone, a couple of cigars and a flask, for when the problem is either beyond my capability to repair beside the road or my repairs have been unsuccessful.

Ed from NJ
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/14/17 12:53 am

Originally Posted by edunham
the most important parts of my toolkit ... is my cell phone,
Even if a phone + credit card tool kit didn't go against my self-reliant approach to motorcycle repair, a phone isn't even a possible substitute for spanners on the Cannonball for anyone hoping for full points. Points are awarded for miles covered without outside assistance, and all winners in previous years have received full points (ties are broken by age of bike + rider).

I already had the forks back on the bike, and now the mudguard, headlamp, handlebars, and controls are back on the forks (it's interesting how much work is compressed into an innocent half-sentence description).

I installed the front tire using the modified Baja No Pinch tool and as a result it has earned a place in my supplemental tool kit. I worked slowly and carefully with it and it took 20 min total to install the tire. Even though I could have done it in half that time had I been hurrying, I realize this still gives RPM a lead going into Turn Two. This means I'll have to hope the Ariel's OHV advantage will let me get by him on the straight before Turn Three.

I confess that in my haste to see how the Baja tool worked I forgot to check the direction of rotation of the tire before installing it. Although mathematically there should be a 50/50 chance of getting it right, we all know the actual odds are close to 0. Despite that, when I remembered to check I found it was on the correct way(!). It took 99.5 g to balance the tire, again achieved using 1/8" Pb sheet.

When I started looking into making modifications to install seals for the wheel bearing grease fix suggested by Richard Kal in an earlier post I discovered seals already in place. This means I only have to deal with the rear wheel, which doesn't have seals.

Posted By: Tridentman

Re: 1928 Ariel Model C - 07/14/17 1:04 am

Comin out on the right side of a theoretical 50/50 is a good omen, MMan.
Must be down to the chickens I have been sacrificing for you.
Posted By: No Name Man

Re: 1928 Ariel Model C - 07/14/17 4:25 pm

My two cents on the Slime issue: I have seen it work very effectively for a semi-long term on other's and my own tires. For my own, it has only been on a new tube which I had just pinched. The feeling of hearing a newly installed tire going hisssss is extremely deflating. I seem to manage to pinch about half of em. Can't say this is a recommendation, just an observation. So far no second leaks on ones I did but the front off a Victor which I had bought was completely green inside. Harder to remove than paint.

Bill E
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/15/17 1:48 am

Originally Posted by Tridentman
Must be down to the chickens I have been sacrificing for you.
I appreciate it, so please keep it up. You've also saved me money. I hadn't had time to follow up on it yet but I located an M.D. in Haiti who sells specially processed chicken entrails ("Which doctor?," you might ask...). I was going to buy a batch, puree it, and use it as tire bead lubricant to keep from pinching tubes.

Originally Posted by No Name Man
My two cents on the Slime issue: ... Harder to remove than paint.
One of the reasons I won't use it.

Originally Posted by No Name Man
The feeling of hearing a newly installed tire going hisssss is extremely deflating. I seem to manage to pinch about half of em.
I have just one word for you: Baja No Pinch Tire Tool. And plastics. So, make that two words.
Posted By: Tridentman

Re: 1928 Ariel Model C - 07/15/17 1:58 pm

Eggsaxctly---Johnsons Baby Powder is sooooo---- expensive these days---
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/17/17 9:18 pm

Having the chicken entrails and baby powder situation under control, it's time to turn to other riding matters.

I realized a birthday is coming up in a month so this would be a good time to create a "gift registry" for motorcycle clothing. So, I've been looking through catalogs trying to decide what to ask my family for. It looks like the most expensive item will be a one-piece Goretex riding suit but I still have to decide on a brand. They're expensive enough that I might have to miss Christmas as well so I'd like to get this right and not be cursing my choice in the rain. Suggestions (based on personal experience)?

All black would, ahem, suit the 'Black Ariel' quite nicely, but I'm afraid there's no choice but to go for something more visible than black.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/20/17 3:51 pm

I had to be away from the Ariel for five days to attend a reception in California, but this gave time for a half-dozen items to arrive.

I was impressed enough by how Magnafluxing had put my mind at ease with the girder forks that I did some more reading about the process. Without going into the details, DC inspection (as I had done with my large electromagnet) is best for detecting sub-surface defects, but AC is best for surface cracks. Basically, a DC field penetrates the entire object so the resulting magnetic field pattern on the surface, where the magnetic particles sit, is an average of whatever flaws or voids are present throughout the volume below. Because of this averaging the sensitivity of DC testing to surface cracks is reduced. In contrast, because the skin depth of a 60 Hz AC field is only ~2 mm the pattern of particles from surface cracks isn't "blurred" by whatever is going on deeper in the specimen so they appear with higher contrast with AC than with DC.

I had decided to make my own portable yoke to allow me to make 'in situ' measurements but just before leaving for this latest trip I came across an older, AC-only, fixed-leg yoke on eBay that I was able to buy with a low enough 'best offer' that fabricating my own made no sense. A large box of mail was waiting on the front doorstep when we returned last night, one package containing the yoke. The Magnaflux site says if an AC yoke is working properly it should be able to pick up a ~10 lb. steel bar and mine certainly does that. Also, since it will be easy enough to make, today I ordered a $7 rectifier to make an electrical adapter box -- 110V AC in, 110V DC out -- to "instantly" switch between AC and DC operation whenever I want.

The field has to be applied perpendicular to cracks in order to detect them. Since this yoke has non-adjustable legs I'll have to machine a pair of pole pieces to allow it to provide a transverse field to tubing, but making those pieces along with adapters to clamp them to the yoke shouldn't be too time consuming.

This yoke should be quite useful for testing a number of things since I won't have to disassemble pieces in order to Magnaflux them. In the case of the Ariel, as soon as I have those pole pieces made I'll check all the lugs on the frame.


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Posted By: RPM

Re: 1928 Ariel Model C - 07/20/17 10:49 pm

Since I am not smart enough to make my own magnet I am buying a kit from Goodson. It cost 800 dollars but we are doing 4 maybe 5 bikes so cost gets easier to bear. I am thinking of getting Goodson kit FCD-HP-KIT . Could not post a link but I think that will work if we remove all the paint. What do you think MM? Of course I have magnet envy.
New pistons from JP pistons arrived. Using alloy ones from a CS1 1929. It uses the 5/8" wrist pin like the earlier SV Nortons. A little higher compression but should be fine. I was happy to see they sent them with 3 compression rings and no oil control ring like later bikes. Not enough oil in the old motors to need oil control ring. Cranks off to Alpha.
Sent a magnetos off to someone new. Got my fingers crossed. My trusted magneto and dynamo guy passed away just a few weeks ago. Mick Hall at FTW did a great job every time for many years. Good guy I will miss his good work
The 1915 Norton we ran last time has been repainted after repairs.Need full gearbox rebuild but I did find a spare gear set for a 1915 Strumey Archer gearbox on ebay. Going to go over it real good. It let us down last year. Going to put small drum brake on front. It has no front brakes to speak of. Annoying on inclines as rear brake and compression release is enough.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/21/17 4:44 pm

Originally Posted by RPM
I am buying a kit from Goodson. It cost 800 dollars but we are doing 4 maybe 5 bikes so cost gets easier to bear.
The total price of the two kinds of powder I bought from Goodson was low enough that I decided it wasn't worth the time it would have taken to search for less expensive suppliers. However, it might be worth a few minutes for you to investigate other companies that sell magnetic yokes. The one Goodson sells certainly would work, but their kit is just the yoke, a UV light, and two kinds of magnetic power and sells for $900.

Used, but guaranteed to work, Magnaflux yokes sell on eBay for under $300 and a UV light is less than $50, so with new bottles of powder you could put together a kit just like Goodson's for not much more than one-third the price. Although it makes sense that Goodson supplies a 100 W lamp since they cater to car people, for what it's worth, although I have much more powerful UV lights the 18 W I used provided plenty of illumination. If I magnetized a V-8 block and wanted to inspect the entire surface without moving the light a more powerful one located further away would be a benefit.

Originally Posted by RPM
New pistons from JP pistons arrived.
Need full gearbox rebuild ... Going to go over it real good. It let us down last year.
Sent a magnetos off to someone new.
You're ahead of me on the engine, gearbox and magneto. Fingers crossed I don't find too much amiss, or unobtainable parts needed, when I get into them.

Turning to the Ariel, the threaded portion of one end of the rear axle was bent by ~0.02" so I marked the high spot, clamped the straight section in V-blocks, and used my 30T press to bring it back to within a few thou. of straight. I also used a small jeweler's file to eliminate a few burrs and polished the axle, allowing the bearings to be pushed on with less resistance than before.

The front wheel bearings have a larger ID than the rear ones and use stepped spacers to match the ID of the bearing to the OD of the axle as well as to provide a surface for the grease seals. The rear wheel bearings have the same ID as the OD of the axle so to install grease seals I machined two short pieces (0.36"-long) of 1.250" OD brass to be press fits over the 1.106" OD projections on the inner races of the bearings. After greasing the bearings and adjusting the tension I put the rear wheel aside with the front one to await return of the backing plates.

I started work on an Al piece to clamp Fe bars in place on my Magnaflux yoke to provide transverse fields to sections of the frame. This shouldn't take long but, of course, already has taken a lot longer than it should take.


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/23/17 4:33 pm

I had to deal with a few minor roof leaks and a clogged inlet to a water harvesting tank which kept me from making much progress on the Ariel itself. However, I did complete the machining of the add-on pole pieces for my Magnaflux yoke. The yoke has 1"x1" legs but the closest magnet iron I had on the shelf was 2"x2". Other than the additional weight larger would be perfectly fine since that would mean the Fe would remain even further from saturation, although it still needed to have smaller faces to concentrate the field lines where they meet the parts to be tested. Ideally the new poles would be laminated like the yoke itself to reduce eddy current losses from the AC yoke but this shouldn't have too much of an effect on performance.

I used a Portaband saw to slice ~45-deg. chunks from one end of each piece leading to 1"x1" faces (offset from the centers of the 2"x2"; the top of the 1"x1" faces are even with the top of the 2"x2" Fe but the bottoms are at the centers of the Fe). I did this because sawing removes material much faster than machining. After making the crude cuts I finished the pole faces with the Fe pieces mounted at 45-deg. in the mill then tapped the bottoms to clamp to the Al holder that in turn clamps to the yoke.

With the yoke modifications now complete I can adjust the gap of the pole pieces and apply transverse magnetic fields to any piece of frame tubing (or headstock) I want.

My younger daughter responded with the designer-approved colors I'm allowed to have for my one-piece rain suit. She also said I have to replace my blue helmet with grey or black because "no more blue! you're over 60!" Hey, I prefer bright "Hockney-esque" colors, but I learned decades ago to slavishly obey whatever style instructions she issued.

Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/25/17 1:23 am

For no good reason I decided to weigh and record the major components as I get to them, as well as the final bike (which is listed at 300 lbs.). The rear wheel including new tire and tube but without the brake backing plate is 33.1 lbs. The front wheel is 25.8 lbs. I normally have the scale on the jib crane that swings over the lathe and mill but I moved it to the engine hoist to make sure I don't forget to measure the engine and gearbox when I lift them out of the frame.

Well, six or so weeks after I began to circle the beast, it's time to go for the heart. With the wheels off, the bike has been balanced on wood blocks under the engine with tie downs keeping it from falling over. Since it wasn't incredibly solid in this configuration I (temporarily) installed the front wheel, jacked the bike up to remove the blocks, and lowered it onto the front wheel and rear stand. Next I removed the carburetor, gearshift assembly, and fuel/oil tank so the engine is now almost ready to be removed (I still have to disconnect the magneto's advance cable and the valve lifter cable).

A year or two ago I fabricated a "universal" 'C'-shaped engine lifting jig that bolts to the head and lets me position the lifting point directly over the center of gravity of an engine and above the top tube of a frame so that I can use my engine hoist to make removal and installation nearly effortless. Just three additional holes and two spacers and the jig will be ready for the Ariel's head. However, the rocker box has to come off first because there isn't sufficient clearance to remove the engine while it is still in place.

Once the engine is out of the frame I'll be able to trace the engine plates in order to fabricate a stand to hold it on the bench to make working on it easier. As soon as I get the engine apart I'll know how much trouble I might be in for replacement parts.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/26/17 4:56 pm

I've been making quite a bit of progress, at least as measured by the number of parts laying on the garage floor rather than bolted to the bike.

In my last post I said I planned to remove the rocker box and then use my lifting jig to remove the engine with the head still on. I hadn't realized how easy it would be to remove the head. For the record, the order for approaching this part of the rebuild is:

-- remove complete exhaust system as a single piece
-- turn engine until both valves are closed
-- unscrew tappets a few turns to make sure all tension is released
-- unbolt tappet box. It's held by two long bolts on the right side (through the head and into the block) and a very short bolt in the center. The two long bolts have to be removed but the short bolt can't be because the frame tube is in the way. The center bolt has to be withdrawn as far as possible and held in that position as the right side of the tappet box is lifted off the pushrod tubes and then slipped sideways out of the frame. Of course, it will be easy to forget to insert this bolt the first when it comes time to rebuild the bike so I expect to do a "trial" installation without the bolt before remembering to do it correctly.
-- Only two short bolts on the left side remain holding the head in place. There's no reason to leave the head on at this point so once these are removed the head lifts off. There is no head gasket. The complete head weighs 12.6 lbs. and with the rocker box the total is 17.2 lbs.

Measured with calipers the bore at the top of the cylinder is 82.7 mm whereas the stock bore is 81.8 mm. Although I'll make a more accurate measurement once the engine is apart on the bench it's pretty clear it's overbored by 1 mm/0.040". However, the top of the piston has lots of nicks in it from bashing something around that dropped in. Whether the damage is fatal, or there are other issues with the piston, won't be known until I take the cylinder off. The Ariel uses a piston with a rather large 1" gudgeon pin so it's unlikely I'll be able to find a suitable replacement on Amazon.com.

Whatever I tried to take off next in order to remove the engine, something else needed to be taken off first. But, before that could come off, something else... This process finally lead me to the rear brake pedal as the keystone to the rest of the disassembly. Unfortunately, it didn't want to come off its shaft and the shape of the pedal and small clearance to the primary cover didn't provide anywhere for a 2-jaw puller to grab. So, I machined a 2"x3" piece of 1/4" steel in the shape of a 'C' to slip between the pedal and the primary case, tapped two 1/4-28 holes in it, and used it with a bolt-type puller to extract the pedal. I assumed the shaft was splined or keyed but it's a simple taper.

The primary cover came off next. Overall, most fasteners on the bike are British, but there are enough metric, A/F, and "other" randomly tossed in to keep it interesting. For example, the nut for the magneto sprocket is 5/8" A/F and, although both bolts holding the magneto started life as BSW, the flats of one of them had been filed down so only an adjustable spanner fits it now.

Only after I had carefully measured the 1/2" pitch of the primary chain and counted the number of teeth on the main engine sprocket (23T) twice did I notice '1/2-23' stamped on it. Oh well, you know what they say, measure twice, confirm once.

The drive chain seems to be new and is marked 'JWIS Germany', which is a good sign, but the master link is no-name. A chain is only as strong as its weakest link. However, the primary chain, also JWIS, is quite worn with 11" sideways deflection over its 40" length. Of course, since this chain was hidden from view by the primary cover the only way I would have known its poor condition was to remove that cover. This is another example showing why I'm completely rebuilding this bike. Even if a primary chain didn't cause any damage when it broke I'd rather not be disassembling the primary case on the side of the road or in a motel parking lot at night to install a new one (assuming I had a new one to install...).

The master link on the magneto chain is marked 'The Coventry' but the chain itself is no-name and also is quite worn with 6-1/2" deflection in 18". Luckily, there is plenty of clearance for X-ring chains for both the primary and main drive chains, which is what I will use for both (80 links for the former, and 95 for the latter).

Since I now know all the sprockets I can calculate the expected performance in high gear when the gearbox ratio is 1:1. A table of speed vs. rpm in an Ariel booklet goes to a maximum of ~5400 rpm so taking that as redline and using Avon's figure of 789.6 turns/mile for the circumference of the rear tire and:

engine 23T
clutch 44T
gearbox 19T
rear wheel 47T

5400 revs/min. x (23T/44T) x (19T/47T) x 1 mile/789.6 turns x 60 min./hr. = 86.7 mph

The highest speed mentioned in Cannonball literature is the ability to maintain 50 mph on straight flat roads, which would be less than 60% of redline with the present gearing. This means the present gearing should be fine for crossing the Midwest. There's even some reserve speed if needed for short stretches on Interstates. Dropped down into 2nd the ratio changes by 1.6 so 50 mph becomes 30 mph. This means the present gearing should be fine for climbing the Rockies as well.

I removed the magneto (6.4 lbs.) leaving just the gearbox (with clutch) and engine to be removed from the frame. However, I can't predict which of those will be removed first because the system of mounting plates is complicated enough that it's difficult to know in advance.

I have a good supply of old photographic developer trays and cookie sheets in a variety of sizes so each major component gets its own tray and sub-assemblies get their own smaller containers to sit within those trays. Once everything within every container and tray has been refurbished the components will get joined back together, nothing will be forgotten and nothing left over, and all will be perfect. Yeh, sure, nothing cann gggo wwwroooongggg .....


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Posted By: KevinN

Re: 1928 Ariel Model C - 07/27/17 11:18 am

Great thread MagMan. Thanks for taking the time to share. I'm looking forward to seeing some pictures!


Kevin, #97
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/27/17 5:42 pm

Originally Posted by KevinN
I'm looking forward to seeing some pictures!
Kevin,

Thanks very much. I'm also looking forward to seeing some pictures...

I've been documenting everything I do with plenty of photographs (if, for no other reason, to help me put it all back together...). But, to incorporate them in this thread, what I need is a "permanent" replacement for Photobucket so I don't spend all the time it takes to edit, resize, upload, and link to photos at some new hosting site, only to have that site change its policy or go out of business. Google Images is probably as close to "permanent" as I could hope for, but as far as I can tell from reading their instructions it would be a headache to use them as a host. That said, I haven't spent much time on that problem as yet, instead spending my time working on the Ariel.

My posts here are always a few days behind where I actually am but, as a teaser, the engine is on my workbench.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/28/17 3:12 am

Even on days when I don't have time to do anything on the Ariel, I try to do something. Yesterday's something was machining a socket to use for accurately adjusting the clutch once I reassemble it. I described the principle behind it in detail in a thread on rebuilding a BSA 6-spring clutch that was better before it was gutted of images by the Photobucket apocalypse.

Anyway, based on measurements of the gearbox housing I started with a 13/16" A/F socket, opened it up slightly with a 7/8" drill, then machined a slot over ~1/4 of its surface of the appropriate shape to clear the clutch arm and housing. With this modified socket I can measure the torque required to move the end of the clutch arm 0.5" just as I had done with the BSA clutches.

From what I've read the Burman clutch has a reputation as being light, and my measurement showed this to be the case with my clutch as it came to me. I didn't test the bike very thoroughly or hard before getting caught up in the rebuild but I didn't notice any sign of the clutch slipping so the adjustment is reasonably good right now. Although I don't know yet what the internals of the gearbox look like, the external arm is about the same length as that of the BSA (2-1/2" vs. 3-1/4", so 77% of the leverage) and the lift of the clutch plates looks to be about the same (to be accurately measured later), which means the internal leverage must be about the same as well. This means the torque as I measure it this way is proportional to the relative pull required at the handlebars for the two gearboxes. For the BSA the torque required to move the end of the arm 0.5" is ~11 ft.lbs. but for the Burman it's only 4 ft.lbs.

There are ~4 threads showing on each of the clutch nuts so there is plenty of adjustment possible to increase the pressure if needed. Also, the pressure plate doesn't lift perfectly evenly now so there's room for improvement. But, having measured and made note of the current settings will make it much easier later to get the clutch operating to the limits of its capabilities after I rebuild it.


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/29/17 3:29 am

Removing the front engine mounting plates was just a matter of removing four studs. Plus supporting the engine with a jack because it serves as a stressed member of the frame so otherwise the lower portion of the frame would sag and make the studs very difficult to remove. Once the four studs were removed two heavy engine plates, covered by two "cosmetic" sheet metal pieces, came off to leave a 6" gap between the frame downtube and the two smaller diameter frame rails under the engine. However, the rear engine mount was a real problem.

The rear mount is semi-circular and comes around the top enough to block the engine from being lifted straight up. It's also welded into a single piece that closely straddles the frame so it can't be easily moved although, when unbolted, it can be moved back just a little which isn't enough to free the engine from the clutches of the frame. Plus, the magneto platform is part of the welded assembly and it extends under the timing chest (it bolts to the timing chest) so the assembly can't be pulled straight up because the engine blocks it. That is, the engine can't move upward because part of the rear mount is in the way, and the rear mount can't move upward because part of the engine is in the way. Sigh...

Before completely removing the front mounts I had attached the engine hoist and put enough upward force on the engine to balance the weight. The solution to removing the engine was to push it as far forward in the frame as it would go where it was then (barely) possible to tilt it just enough to allow the magneto platform to clear. Once clear of the timing chest the rear mount assembly could be wiggled upward and out of the frame. At some point in doing this a spacer I hadn't noticed before dropped out -- I hope I can find where it goes before it all goes back together and I discover the spacer has to be installed before it all goes back together. With the rear mount out of the way I moved the engine back to the center of the open space but it still had to be rotated maybe 5-deg. CCW to escape the frame.

I can't see there would have been any way I could have removed the engine without my lifting jig and engine hoist. It's not just that these made it easier, which they did, they made it possible. I can't see how two people could have done it, either, at least without a lot of collateral damage to paint and engine surfaces. However, having gotten the engine out of the frame, I'm now afraid it may require divine intervention to get it back in since it's like one of those metal puzzles whose two pieces only can be separated if you know how to cleverly maneuver them in just the right way.

As removed the engine weighed 56.4 lbs. so with the head and rocker assembly the total weight of this Ariel engine is 73.6 lbs.

Prudence would have had me wait to remove the cylinder until I had made a stand to firmly hold the engine, but what does Prudence know about motorcycles, anyway? So, at the risk of doing something stupid and having the top-heavy engine crash to the floor, I worried the cylinder off (weight 10.8 lbs.) to expose the piston.

The piston is a "modern" one with split skirt and 13/16" gudgeon pin rather than the original 1" as well as having two compression and one oil control ring. There are a lot of marks on the top where it had bounced something around while running earlier in its life but I can make out '040' and the letters 'D2' above it. Also, 'Front'. So, as my calipers had indicated a few days ago, the cylinder has been bored 0.040" over.

When I take the piston off I hope I find a proper engineering solution was used to reduce the small end rather than just a piece of brass. Even better, I hope I find it has a "modern" rod with a 13/16" small end. Not that 60-over pistons for later Ariels are all that cheap and common. And then there's the issue of balance factor. But, for now, I couldn't feel any up/down motion of the connecting rod, which ends this post on a promising note.



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Posted By: KevinN

Re: 1928 Ariel Model C - 07/29/17 3:40 pm

Good progress on the engine MagMan.

I use SmugMug for hosting my photos. I've been using it for a long time, so I don't know how it compares to other services. I will say that I find photo sharing on forums is easy to do from SmugMug, using either my desk/laptop or my iPad.


Kevin
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/29/17 4:36 pm

Originally Posted by KevinN
I use SmugMug for hosting my photos.
Kevin,

Since your photos hadn't disappeared with Photobucket I already had right clicked on one of them to see who you used as a host. I did this for others as well.

My concern with SmugMug, and others, is their long-term viability/stability. I can think of at least three large photo hosting services for professional photographers -- which is SmugMug's background -- that shut down in recent years, and there well may have been others. A huge amount of my time was lost as a result of Photobucket's change in policy and I want to minimize the chances of that happening again.

According to Wikipedia SmugMug is still owned by the father/son team who founded it 15 years ago and all they have to do is decide it's time to cash out for things to change. Hoping for "permanence" on the web is futile, but I'd like good odds of at least a decade before committing time to a new site.

Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/30/17 5:30 pm

I woke up Friday to an email from Michael Morse of Vintage Brake saying my front and rear brakes are done and ready to ship back to me. Fantastic! I can't say enough good things about MM/VB, who I've had do the brakes on four bikes that I can think of over the past 20 years. All have performance approaching that of disc brakes.

When I sent the backing plates to him I described the bike and how I would use it and he decided on VB3000 compound, about which his site says "High friction compound with consistent feel and performance at all duty levels and rotational speeds, for off road and street use." I hope I don't find myself testing the Ariel's off road performance... It goes on to say "Good first stop capability and with excellent water dispersal." That is, it works well without having to be warmed up, and works well in the wet. Both are what I want. Although the description doesn't mention fade resistance, which isn't important for the Ariel, apparently it's not bad at all. It's just that he has other compounds that are better where that matters, like racing. In addition to bonding the compound and arcing the shoes to the dimension of the drums he replaced two rusty springs.

He asked me what wheel bearing grease I would be using (Sta-Lube High Temp Disc Brake Grease). He said he used to paint the shoes he relined and knew the temperature where it discolored, and some shoes that came back to him at the end of a racing season that weren't discolored by heat had signs of grease splattered around despite the claimed drop temperature of the grease being higher. As a result, he recommends Extreme Temperature grease since it has a drop temperature of 500 oF. I then checked and the Sta-Lube has a drop temperature of 450 oF. However, I discovered I have a can of Mobil 1 Synthetic Grease, also recommended for wheel bearings, and it has a drop temperature of 550 oF. Anyway, even though it's almost certainly not necessary for the way the Ariel will be used, I'm going to take the time to thoroughly clean out the Sta-Lube and replace it with Mobil 1.

Michael has now shipped the brakes back to me but I'll be in a state of anxiety for the next few days until they arrive, hoping that UPS doesn't misdirect or lose them. I've already checked and Amazon doesn't sell 1928 Ariel backing plates so to lose them would be a serious setback.

I've now removed the piston so I can see what's underneath. It's a Hepolite (Heplex) 10793, with other markings 3160AM, 413 and AF3. A pdf on the Draganfly web site lists this as a 6.3:1 piston for 1935-58 Ariel VG/VF/VH Red Hunters. The total weight with rings and wristpin is 466.5 grams.

The casting on the rod is A6/247, the number in the parts manual, not 'Carillo', so it's the original rod. The ID of the small end is 1-3/16" so a thin bushing would have been used to reduce that to the 1" OD of the original wrist pin. Instead, a fat bushing of reddish brown color, consistent with it being a bearing bronze, reduces the small end to 13/16".

The hunt is on for a replacement piston and a spare, assuming the engine will need decoking on the "day of rest" halfway through the Cannonball. If it does need decoking it will be a lot easier to swap pistons (assuming the OD of the replacement is close enough to that of the original). Note to self: bring hone to break the glaze.


Posted By: Lannis

Re: 1928 Ariel Model C - 07/30/17 6:37 pm

Originally Posted by Magnetoman
I woke up Friday to an email from Michael Morse of Vintage Brake saying my front and rear brakes are done and ready to ship back to me. Fantastic! I can't say enough good things about MM/VB, who I've had do the brakes on four bikes that I can think of over the past 20 years. All have performance approaching that of disc brakes.


My experience with Vintage Brake has been the same. Only thing is, you need to time your brake work with the racing and summer schedule; he stays booked up solid during that time, but will tell you as accurately as he can just when he will be able to get to yours. Don't look for next-week turnaround!!

Lannis
Posted By: chaterlea25

Re: 1928 Ariel Model C - 07/30/17 10:09 pm

Hi MM,
In my experience decoking is not necessary after say 2000 miles (half way)
With modern oils and a piston with an oil ring or even without one I have found that when set up properly vintage bikes in general
do not coke up to any degree that is detrimental to performance
When rebuilt I'm confident that the Ariel's engine would do the event several times over without surgery
Selecting material for the valve guides and some decent quality valves will enhance the reliability
Keeping road dirt away from the valve/ guide area will help a lot

John
Posted By: kevin roberts

Re: 1928 Ariel Model C - 07/30/17 10:53 pm

magneto, time for some pictures of where you're at. dunno where you want to store them, but i for one want to see that ariel again.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/31/17 6:40 pm

Originally Posted by kevin roberts
some pictures of where you're at. dunno where you want to store them
Pictures of the entire rebuild await uploading from my computer once that problem is solved by Morgan or someone else.

Originally Posted by chaterlea25
Selecting material for the valve guides and some decent quality valves will enhance the reliability
Keeping road dirt away from the valve/ guide area will help a lot
I should be getting to the valves and springs before much longer. Unfortunately, I don't see any obvious way to enclose (or semi-enclose) the valve/guide area without degrading air flow to the cooling fins of the iron head. But, maybe once I start work on it I'll see a way to avoid dirt without affecting cooling.

Originally Posted by chaterlea25
In my experience decoking is not necessary after say 2000 miles (half way)
This is welcome news. It will save a lot of money (for a second piston) and time (taking off the head at the halfway point and discovering the 2nd head isn't needed). But, a new poster to this thread (KevinN) rode an old inlet-over-exhaust Harley in the previous Cannonball and wrote elsewhere that he decoked it every few days. KevinN, if you're still following this thread, was the decoking you did essential, or incidental to other work? Was the carbon buildup primarily around the exhaust port, which might be hotter than mine(?) because of the flathead design of that part of the head? RPM, did you have to decoke your Nortons?

On the subject of the piston, I've now made measurements of it and of the bore. I carefully calibrated my tenths-reading 3"-4" micrometer before starting, and used that micrometer to zero the bore gauge with its own tenths-reading dial, so the absolute and relative values of both are accurate to ~0.0001" (a tenth of a thou.) I'll just give representative data because I measured the piston and bore at the top, middle, and bottom and front-to-back as well as side-to-side so there is a lot of data.

For the piston clearance an old Hepolite sheet recommended 1 thou./in., for ~3 thou. total. For a Gold Star BSA recommended 2.5-4.5 thou. total for touring models and 4-6 thou for competition. Measured just above the bottom of the skirt from front-to-back the clearance of my Ariel's piston is 5.1 thou. when at the top of the cylinder and 4.4 thou. at the bottom. Side-to-side clearance is quite a bit more at 14 thou.

As for the rings, an old Ariel manual recommends 6-8 thou. end gap. Other recommendations are 3 or 4 thou./in. which would be 9-12 thou. What I found was the top compression ring was gapped at 22, the bottom at 25, and the oil ring at 26 thou.

The cylinder is round to within 0.2 thou. at the top and 0.3 thou. at the bottom. The cylinder tapers by ~0.7-0.8 thou. from top to bottom. Although vertical lines run from top to bottom around the entire circumference of the cylinder wall it feels glass-smooth to the touch. Either the rings were fully bedded in or it wasn't properly honed to begin with. I have to wonder if the vertical lines are due to the cylinder not having been thoroughly cleaned of abrasive after honing.

All in all, the piston and bore (but not the rings) are within reasonable spec, all things considered. From this data it seems the cylinder either was bored specifically for this 40-over piston, or it had been previously bored for a 40-over piston and the present one happened to fit "good enough". However, the piston is quite scuffed (i.e. vertical scratch lines), especially on the front and back faces but also to some extent near the bottom of the skirt on the sides as well, and nicked all over the top from bouncing something like a piece of broken piston ring. Unlike the lines on the cylinder wall, which are more like stains than scratches, the scratches on the piston are quite rough.

OK, from the above I can tell the previous rebuilder installed a very worn 40-over piston using too-wide ring gaps in a cylinder that had been bored to reasonable, although not precision, tolerance. If I had another 40-over piston on the shelf, which I don't, I could hit the cylinder with John Healy's favorite 180-grit hone and see if the clearance was OK-ish enough to use that piston. But, I don't have another piston of any size so it seems the only reasonable thing to do is look for a suitable 60-over piston and bore the cylinder to match.

One possibility to look for as a replacement is a similar "later" Ariel piston, although in 60-over. Although they don't have it in 6:1, Draganfly shows "excellent" stock levels for their 60-over 7.5:1 pistons for later Ariels, which are of an unspecified aftermarket brand. Everything I've found about aftermarket Ariel pistons says all of them are very heavy. So, one issue would be how much material I could remove from the skirt without weakening it, to minimize work on the flywheel to rebalance it to the best-guess balance factor. Similarly, how much I could remove from the crown to reduce the CR without weakening it. Or, would the iron head be able to deal with the extra heat generated by the higher compression? Comments and suggestions encouraged. Chaterlea25? Others?

While pondering the piston I got started making a torque plate from a piece of 6"-dia. x 3/4" steel. I've made quite a bit of progress with it but there is still a lot of metal to be removed to make the necessary ~3.5"-dia hole. Yes, I know, a torque plate might be overdoing things, but there's no reason not to the best job possible even if the improvement might be minimal.



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Posted By: chaterlea25

Re: 1928 Ariel Model C - 07/31/17 10:28 pm

Hi MM,
Original Ariel bore size is 81.8mm, but you did not give us the actual bore size now?
Is it more than 81.8 + 0.040in an by how much

Since the Ariel engine is not through bolted (as far as I know) I do not see the point of a torque plate? or am I missing something?

It might be worth contacting this ebay seller to see if he has any other bigger Ariel pistons
http://www.ebay.co.uk/itm/Ariel-500-Piston-Rings-set-VG-VH-Red-Hunter-030-NOS-New-Old-Stocked-VHB-VHA-/232420791779?hash=item361d5bd5e3:g:t50AAOSwpP9Y6FeP

I believe Draganfly's pistons are made by JP which have mixed reviews ????
There's quite a long discussion on Ariel pistons on the owners club forum
Our friend Paddy's Ariel is running quite happily with its capacity boosted to 545cc using a BSA 85mm piston
I did not measure the compression ratio but its easy to start on the kickstart ,
It does feel a bit viby though?
Some Years ago it was popular to fit Ford pistons ??
I will ask Paddy to bring along the old +060 piston removed from his engine when you are here in a couple of weeks

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 07/31/17 11:37 pm

Originally Posted by chaterlea25
Original Ariel bore size is 81.8mm, but you did not give us the actual bore size now?
Is it more than 81.8 + 0.040in an by how much
Oops, sorry if what I wrote was incomplete. As you say, the original bore size was 81.8mm/3.2205". Ignoring deviations from round the largest bore is at the top (measured front-to-rear) at 3.2607"/82.82mm, i.e. 2 ten thousanths larger than +0.040". The smallest bore is at the bottom (side-to-side) at 3.2597".

Have to run. More later...
Posted By: RPM

Re: 1928 Ariel Model C - 07/31/17 11:37 pm

We have done nearly 4k miles on the 1915 without removing top end. We do try and run really good gas as much as possible.
The piston clearances sound fine to me. Rework the piston you have and hone, new rings.
The Norton has cast steel piston that we welded we found a crack when we first got it. It is round and not elliptical. We run Total seal rings. Total seal recommended not running an oil control ring on a total lose system. The Norton uses four 1/16" rings in two 1/4" grooves. Has been working well.
JP pistons has mixed reviews? I just bought two so we will find out.
Torque plate is a waste of time.

Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/01/17 1:40 am

Originally Posted by RPM
We have done nearly 4k miles on the 1915 without removing top end.
The piston clearances sound fine to me. Rework the piston you have and hone, new rings.
That confirms what chaterlea25 wrote so I won't look for a 2nd piston. Thanks to both of you!

I'm hoping for a better option than the worn current piston. But, it remains an option.

Originally Posted by chaterlea25
Since the Ariel engine is not through bolted (as far as I know) I do not see the point of a torque plate? or am I missing something?
Originally Posted by RPM
Torque plate is a waste of time.
Even though there aren't through bolts, just the 4 bolts holding the head will distort it to some extent. "To what extent?," you ask. Since I'm far enough into making the torque plate I'll finish it. I'll then measure the out of round at the top of the cylinder with and without the plate torqued down and report the results (even if they show I wasted my time making it).

Originally Posted by chaterlea25
It might be worth contacting this ebay seller...
No luck.

Originally Posted by chaterlea25
I believe Draganfly's pistons are made by JP which have mixed reviews ????
There's quite a long discussion on Ariel pistons on the owners club forum
I've read that thread and the relevant parts of it already are included in my "shop manual." That said, I didn't find the information there very useful, and much of it sounds like people just repeating what they think they remember having heard.

Gold Star pistons are mentioned, but when I measured mine I found the crown significantly higher than on the Ariel (1.30" GS vs. 1.20" Ariel from the center of the gudgeon pin to the land). This could be dealt with by making an offset reducing bushing for the small end but the fact no one mentions it indicates to me that the people writing those GS posts are repeating hearsay. Further, a GS piston has a much higher crown to give it the higher CR so something would have to be done about that to bring it down. Also, no one mentions having measured the balance factor, again indicating to me that the technical information might not be entirely reliable. In this context, complaints there about JP pistons may or may not have basis in fact.

Originally Posted by chaterlea25
Our friend Paddy's Ariel is running quite happily with its capacity boosted to 545cc using a BSA 85mm piston
Do you know if Paddy installed it himself (i.e. will know first hand the engineering issues to be dealt with), or did he have someone else install it for him?

Originally Posted by chaterlea25
I will ask Paddy to bring along the old +060 piston removed from his engine when you are here in a couple of weeks
Excellent. Thanks.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/01/17 5:21 pm

Update: Plan B (or C) would be to reuse the current, worn piston. RPM mentioned in an earlier post that he bought rings for his old Nortons from Total Seal so I contacted them. Unfortunately, they can't supply the necessary rings so, unless another supplier is located, this would mean to use that piston would require reusing the old rings having gaps that are too large.

To move forward I've ordered a +60 aftermarket piston from Draganfly as my new Plan B. As for Plan A, well, there still isn't a Plan A...
Posted By: gREgg-K

Re: 1928 Ariel Model C - 08/01/17 7:00 pm

MM, if could you post the key dimensions of your piston, I'll see if I have anything suitable here. The following dimensions will be helpful:
- Skirt length from gudgeon pin center to bottom of skirt
- compression height, from gudgeon pin center to top of piston (excluding any crown ... I assume it's flat anyhow, correct?).
- gudgeon pin diameter

I'm thinking I may have something for an easy overbore to 84mm, and rings would be much easier to source.

... Gregg
Posted By: chaterlea25

Re: 1928 Ariel Model C - 08/01/17 10:13 pm

Hi MM,
The piston fitted to Paddy's bike is a long rod B33 and is flat topped compression height is the same as Ariel
There's a company in UK who supply only piston rings in every possible size
I will dig out their details

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/01/17 10:57 pm

Originally Posted by gREgg-K
MM, if could you post the key dimensions of your piston, I'll see if I have anything suitable here.
Thanks very much for your offer to do this. Going only by the bore an early Matchless (82.5mm) and a Vincent (84mm) are two close possibilities, but whether or not either would work depends on the critical dimension from the gudgeon pin to the crown and I haven't spent enough time yet to locate that information. A number of modern bikes also have 83mm and 84mm bores, but the same issue applies to them as well. Interestingly, pistons for modern bikes have crowns that are rather flat, like the Ariel's, because engineers learned hemispherical combustion chambers with high domed pistons aren't the way to achieve good combustion.

The less important dimension from the bottom of the Ariel's skirt to the center of the wrist pin of is 1.63", and the important dimension from there to the top of the piston is 1.19". The outer ~1/2" of the piston is flat but then gently rises by 0.25" to a small dome. The CR is 6.3:1 but the original piston was 6.0 so would have been even flatter. I haven't yet measured the volume of the combustion chamber but once I do it would be possible to estimate the height of the dome, if any, on the original piston.

Originally Posted by chaterlea25
The piston fitted to Paddy's bike is a long rod B33 and is flat topped compression height is the same as Ariel
There's a company in UK who supply only piston rings in every possible size
I will dig out their details
In light of this I'll go through all 17 BSA singles pistons I have in a box and see if any of them are for the older engine. All I made note of was their OD. Thanks very much for this information. Pistons -- and rings -- for pre-'53 BSAs should grow on trees, relatively speaking, compared with those for Ariels. However, it would be great if a company supplied rings for my current Ariel piston because that would make it a viable option, which it currently isn't thanks to, if nothing else, the too-large end gaps.

This afternoon I'm working in the house so I don't miss the UPS delivery of the Ariel's brakes (signature required), but I'm anxious to get out to the garage and go through that box of pistons.

Posted By: Tridentman

Re: 1928 Ariel Model C - 08/01/17 11:33 pm

Hi MMan---just let me throw something into the pot ref piston ring end gaps.
My first job out of university in the 1960s was working as a development engineer at the Associated Engineering Group R&D Center just outside Coventry in UK.
Associated Engineering was of course AE and the group included at that time Hepworth and Grandage (Hepolite pistons), Wellworthy (pistons--mainly for diesel engines). Glacier Metal Bearings, Coventry Radiator and Presswork (radiators and heat exchangers) among a whole range of engineering companies.
On a personal note after working on projects such as plasma metal spraying to reclaim worn turbine blades on aircraft engines and electrochemical machining I moved onto heat exchanger research and development (which in itself later included developing the oil cooler for the Triumph/BSA triples).
However for a long time I shared an office with a development engineer working on pistons and rings.
He spent much of his time doing finite element analysis on piston design and then running real life tests to validate his conclusions.
However at one stage he was asked by Hepolite to do some work to quantify the effects of piston ring end gaps.
Tests were carried out on a single cylinder research engine which was about 400cc.
Rings were tested with various ring end gaps and the effects on engine output and oil blowby were measured.
The results were quite surprising.
There were no measurable differences in output or blowby with ring end gaps varying from the normally quoted figures up to 1/8".
No tests were done at ring end gaps of over 1/8" as the test planning considered that 1/8" would be ridiculously high.

And the moral of the story is?------
If I were you I would not worry too much about ring ends gap per se--as long as other aspects of the rings and pistons are good.
HTH
Posted By: gavin eisler

Re: 1928 Ariel Model C - 08/01/17 11:41 pm

I dont think the ring gaps are too large, its not new but it will run OK like this if you cant get a new piston, I would be more worried about the ring to land clearance , i.e the "tightness " of the ring in its piston groove , if this zone wears the rings don't function well.
I also think the 5 thou piston to barrel clearance will be fine, its not ideal but its not terrible either, looser is better than too tight, especially on these old iron motors with constant loss oiling. the bore is a little worn top to bottom but not severe, if the motor ran with no real air filter that may account for the marks on the bore.
In your position, if a suitable replacement wasnt available and if the rings are not walloping about in their grooves I would be happy to refit these parts after tarting up the piston.

Posted By: gREgg-K

Re: 1928 Ariel Model C - 08/02/17 1:26 am

I had some time tonight, so I made some measurements on the piston I was thinking of. Here are the numbers I came up with:

- Center of gudgeon pin to crown (flat top). I believe this is what Hepolite calls the "Compression Height", - it is 1.6"
- Overall height of piston, from the crown to the bottom of the skirt - 3.4"
- Gudgeon pin diameter - 0.750"
- nominal bore diameter - 84mm
- Rings - 3 x plain rings - 0.065" thick x 0.157" deep

Hope this is of some help,
.. Gregg
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/02/17 1:44 am

Originally Posted by Tridentman
If I were you I would not worry too much about ring ends gap per se--as long as other aspects of the rings and pistons are good.
Originally Posted by gavin eisler
if a suitable replacement wasnt available and if the rings are not walloping about in their grooves I would be happy to refit these parts after tarting up the piston.
Hmm, this is valuable information to add to the decision tree. Thanks, guys. I've thought of reusing rings as like reusing condoms; something you don't do. But, both of you are saying you would do it, even if there's a large gap. With rings, that is.

I can get a 0.002", but not a 0.003", feeler gauge into both compression grooves along with the rings and can almost get a 0.003" into the oil groove so that aspect of the piston is pretty good.

Originally Posted by gREgg-K
- Center of gudgeon pin to crown (flat top). ... is 1.6"

Thanks very much for looking but 1.6" vs. 1.19" clearly won't work. Do you know what bike the piston is from? Knowing that would let me eliminate it from future searches.

A huge weight was just lifted -- UPS dropped off the brakes. All the components of the bike are back under one roof.
Posted By: gavin eisler

Re: 1928 Ariel Model C - 08/02/17 8:58 am

I have a B44 piston ( omega brand) to hand, pin centre to flat rim is a shade under an inch, the dome to rim is about 1/2 " , sadly they are 79 mm, but if sleeving is possible these might be use-able, pin diam is a nominal 3/4 ". Triumph twin 80 mm pistons also have a fairly short pin to crown height .i dont have one to hand but they fit my long stroke A65 / A10 crank motor without needing taller barrels ( indeed they are so much shorter than stock A65 pistons that the barrels had to be shortened). Again both these options would mean sleeving, i dont know if this is viable for your barrel,
personally , I would delay any boring / sleeving works until absolutely necessary, ( if it isnae broken, dinnae fix it). Ariel barrels were famously seasoned in the raw cast form for a year or two, to let the castings mature, yours must be perfectly "ripe " by now.
Posted By: Tribsauk

Re: 1928 Ariel Model C - 08/02/17 10:14 am

http://www.fwthornton.co.uk/8.html

This company helped when I needed a set of rings for a early BSA M21.. If you need ring specs for Ariel pistons I have old Hepolite ring books with info .. Dave
Posted By: gREgg-K

Re: 1928 Ariel Model C - 08/02/17 1:44 pm

Originally Posted by Magnetoman
<SNIP>
Originally Posted by gREgg-K
- Center of gudgeon pin to crown (flat top). ... is 1.6"

Thanks very much for looking but 1.6" vs. 1.19" clearly won't work. Do you know what bike the piston is from? Knowing that would let me eliminate it from future searches.
<SNIP>

Wow, that 1.19" compression height is certainly odd for such a large piston, and clearly this piston's 1.6" compression height won't do.

I should have mentioned that the piston originated from a 1930's 500cc Royal Enfield model J.

Good luck,
... Gregg
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/02/17 3:09 pm

Originally Posted by gavin eisler
Again both these options would mean sleeving, i dont know if this is viable for your barrel, ...
personally , I would delay any boring / sleeving works until absolutely necessary,
Thanks very much for checking those pistons. I'm not a fan of sleeving so if that were my only other choice I would rather take my chances on the aftermarket +40 piston now on its way to me from Draganfly (FWIW they also have sleeves to bring the barrel back to stock bore).

I don't remember the precise exchange, but one of the Apollo 13 astronauts was asked what someone should do if faced with their ship having a malfunction that would be fatal in ten minutes. He said something like they should spend nine minutes analyzing the possible solutions, then spend the last minute implementing the best one. That's my plan with the piston. After gathering all the information on possible substitutes, sourcing replacement rings (if available) for my current piston, buying an aftermarket +40 piston, etc. I'll decide what seems like the best solution given the options at hand.

Originally Posted by Tribsauk
http://www.fwthornton.co.uk/8.html
This company helped when I needed a set of rings for a early BSA M21.
Thanks very much -- enquiry just sent to them asking about +30 rings.

Update: I quickly heard back from them that they have modern rings from JP in stock for £40.45, so re-ringing the current piston is a viable option.

Originally Posted by gREgg-K
Wow, that 1.19" compression height is certainly odd for such a large piston
That dimension seems to be all over the place, not just for old piston designs but for modern ones as well.
Posted By: kommando

Re: 1928 Ariel Model C - 08/02/17 4:42 pm

I would be wary of JP rings, there are reports of them never bedding in and when I met up with a set on a Matchless piston and tried to use my fingers to spread them enough to remove them they drew blood they were so stiff and had to revert to the proper tool, never had to do that before on any rings.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/02/17 5:05 pm

Originally Posted by kommando
I would be wary of JP rings, there are reports of them never bedding in
Unfortunately, thus far they are the only port in this storm. Also, if the Draganfly piston turns out to be JP, the rings that come with it also will be JP.

John Healy has emphasized the importance of grit for the rings. He doesn't get reports of bedding problems from shops that use coarse 150-180 grit hones, and he does get reports from those who ignore his warning and use the finer grit that's appropriate for modern rings.
Posted By: kommando

Re: 1928 Ariel Model C - 08/02/17 6:30 pm

I know John's warnings but they are referring to cast iron rings needing a surface to wear against so they seal, these are the rings I am used to and if honed correctly will bed in quickly with a dry installation. The JP rings were stiffer by a significant amount, the bike they came out of had seized as it was driven off the driveway because JP had not machined the ring relief area, we were trying to get the rings off to mount the piston on a lathe to machine the relief.

For non Britbike JP experience

https://forum.bmwbike.com/read.php?10,1426,1428

Quote
and piston rings are so hard that very aggressive hone is required. Bedding in takes about 3000 miles if at all.
Posted By: Tridentman

Re: 1928 Ariel Model C - 08/02/17 6:36 pm

Hi Kommando,
The BMW reference was over 16 years ago.
Was your personal experience very recent?
Posted By: norton bob

Re: 1928 Ariel Model C - 08/02/17 8:22 pm

If the fitted piston was running well, not burning oil ,not noisy ,then I would not dream of changing it. The ring gap is unimportant if there is good compression. Too much clearance in the ring grooves would be something to consider but this is a relatively low stressed motor and ring problems not usual. My 500 36 Rudge has a Gold Star piston and they are routinely set up with 8 thou clearance to avoid seizure !!. and usually don't fit an oil ring. They run up to 90 plus mph on the road. Piston clips I would change, Brass end pads (if fitted) I would drill to stop expansion pushing the pads out. Do you have time to run in a recon bore?.
Posted By: Alan_nc

Re: 1928 Ariel Model C - 08/02/17 8:59 pm

Bob's comment on the piston clips is a good one. I think most of us have had a piston clip come out the exhaust port at one time or another in our lives.....sure makes a mess on it's way out.
Posted By: kommando

Re: 1928 Ariel Model C - 08/03/17 9:35 am

TM, about 5 or 6 years ago but at B50.org the issue has come up more recently but easily fixed with alternative rings, that may not be an option in MM's case.
Posted By: Tridentman

Re: 1928 Ariel Model C - 08/03/17 11:49 am

Thanks for response, K.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/03/17 2:59 pm

Guys,

All your piston, clearance, circlip, etc. suggestions duly noted and will be factored into my final decision on how to proceed once I've explored all options that I can think of. Thanks.

The latest news is JP can supply the rings for my old piston but say that at the stock depth of 0.112" they won't have much tension and ask if I can deepen the grooves to take 0.140" rings. I don't yet know what material they're made with, but the low tension seems counter to the experience kommando described from several years ago.

Update: I somehow overlooked it before, but I learned this morning that a few years ago the Ariel Owners Motor Cycle Club (AOMCC), of which I'm a member, had commissioned Omega to make pistons. I emailed the person handling these spares, got a quick response, and just now ordered a complete 7.5:1 piston. So, I now have two different aftermarket pistons on their way to me from England. I may hold off on ordering rings for my current, worn Hepolite. Unless I'm running short of time, in the interests of science I'll toss all three in the oven to accurately measure their thermal expansion since unverified statements/speculations on the subject are to be found.

There's more to a healthy piston and cylinder than being gluten-free and having the correct bore and clearance. I cleaned the base of the cylinder and set it on a surface plate using Brown & Sharpe Ultra-Precision Parallels (accurate to 0.0002") to support it on its base rather than the protruding spigot. Since the base bolts to the crankcase this ensures the bore is perfectly perpendicular to the base and hence to the crankshaft. Or, so it should be. In the case of the Ariel the first problem was the base rocked on the parallels indicating it isn't perfectly flat. A 0.011" feeler gauge at the low corner stopped the rocking.

Next I set my Brown & Sharpe cylindrical square (accurate to 0.0001") inside and pushed it against the cylinder in different locations. In the worst location the cylindrical square made contact with the cylinder at the bottom but I could slip a 0.013" feeler gauge between it and the cylinder at the top, which means the cylinder bore is not perpendicular to the base (if it were perpendicular, the cylindrical square would be in full contact with the cylinder wall no matter the location). Although the tilt is all or mostly in the fore-aft direction rather than side-to-side, even if entirely fore-aft this it still would be an issue since I'm trying to rebuild the engine as well as is possible.

I then thoroughly cleaned the protruding top flange (that seals to the head, the same way as with a Gold Star) of carbon and set the cylinder upside-down on the surface plate and found 0.005" tilt in the fore-aft direction. Since this is likely how it would have been held if bored on a table-type machine (in which case the tilt would have been 0 with respect to that flange; unless the spindle of the machine wasn't perpendicular to the table -- there are so many places where things can go slightly wrong if assumptions, rather than careful calibrations, are made...) it indicates to me that a separate boring bar probably had been used. I then mounted an indicator on a height gauge and ran it around the very rough mounting surface of the base to look at the warping in different locations. However, I didn't do this carefully since, no matter what, I already knew I would have to skim that face to make it flat and perpendicular to the bore.

Note that these measurements don't indicate how far the cylinder currently is from perpendicular to the crankshaft axis since to know that also requires determining the relationship of the top face of the crankcase to the axis of the crankshaft, which I can't measure until after disassembling the bottom end. However, I do know there is a ~0.005" step between the two case halves, which is another related problem to address as part of "blueprinting" this engine.

I can deal with rectifying the cylinder independent of the bottom end. I'll (somehow) accurately mount the cylinder upside down on the mill with the cylinder itself perfectly (or as close to it as my instruments can make it) parallel to the spindle axis. Or, if my final solution will be to overbore it for a +40 piston, and since it's already close, I'll just mount it directly on the top flange and then skim the bottom so both are parallel to each other and will be perpendicular to the cylinder after boring. At that point it will be ready for boring using either the top or bottom flange for mounting. Even if I reuse the current piston, having the bore precisely perpendicular to the crankshaft is better than not.

I didn't want the engine tottering on the bench any longer so I made a stand from an 11" piece of 2"x2" Al 'U' channel with vertical Al arms and bolted to a 7" piece of 2"x6" lumber to give it a wider base. It's a lot more stable now, as well as easy to move around on the work bench.

I also finished hogging out the ~3" hole in the steel for the to-be torque plate. In all ~6 cu.in. of steel had to be machined away to create this hole so it took some time. I still have to finish the ID to size and drill the four holes for the mounting bolts.

As I wrote in a previous post, when done I'll measure the distortion near the top of the cylinder to 0.0001" before and after clamping down with the torque plate and report my findings so people will know whether they should do this themselves, or if I foolishly just wasted several hours of my life machining something that makes little or no difference. The four head bolts are 3/8"-20 and a BSA A65 manual lists 30 ft.lbs. for head bolts of this size so that's what I'll use.

2nd Update: I've now finished the torque plate and used it through four torque/untorque cycles, each time measuring the bore along the bolt-to-bolt axis as well as the axis midway between bolts using a Mitutoyo bore gauge with 0.0001" indicator. I made the measurements at the estimated distance to the top ring when at TDC. Before reporting the results (which might or might not be 0), here's your chance to go on record predicting whether or not I wasted my time making this torque plate. My steel plate is 6" dia. x 3/4" thick with a 3.6" ID hole in it. I torque the bolts to 30 ft. lbs., approaching that value in steps on each bolt. It mounts to the top surface of the muff, not against the top of the protruding cylinder liner. Whoever comes closest to predicting the correct result to the nearest 0.0001" without going over (and 0 certainly is a possible prediction) will win a prize of something to be determined later. In the case of ties for the correct answer, whoever posts first wins. (The one person who've I've already told the result is disqualified, as are all other dodgy Aussies who might have learned it from him).


Attached picture IMG_5580.JPG
Attached picture IMG_5579.JPG
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/04/17 7:02 pm

Since some of you might not have seen the "2nd Update" I added to my previous post, and since none of you have yet responded to it despite ~100 views of this thread since it was posted, I'll repeat it here and then add some new information:
Originally Posted by Magnetoman
2nd Update: I've now finished the torque plate and used it through four torque/untorque cycles, each time measuring the bore along the bolt-to-bolt axis as well as the axis midway between bolts using a Mitutoyo bore gauge with 0.0001" indicator. I made the measurements at the estimated distance to the top ring when at TDC. Before reporting the results (which might or might not be 0), here's your chance to go on record predicting whether or not I wasted my time making this torque plate. My steel plate is 6" dia. x 3/4" thick with a 3.6" ID hole in it. I torque the bolts to 30 ft. lbs., approaching that value in steps on each bolt. It mounts to the top surface of the muff, not against the top of the protruding cylinder liner. Whoever comes closest to predicting the correct result to the nearest 0.0001" without going over (and 0 certainly is a possible prediction) will win a prize of something to be determined later. In the case of ties for the correct answer, whoever posts first wins. (The one person who've I've already told the result is disqualified, as are all other dodgy Aussies who might have learned it from him).

To test if clamping down directly on the protruding sleeve might have a different effect than clamping on the muff I used a 4-1/2" blank of 5/8" steel. Since the DRO was still turned on, and the hole coordinates noted, I put a piece of that steel in the mill and cut the four slots in the edges needed to clear the bolts. I then used my torque plate to clamp this new one to the protruding flange of the cylinder itself, simulating even closer what happens when the head is attached, and measured the possible distortion from the other end of the cylinder to see if it was the same (which might have been 0) or different than the torque plate alone.

Some of you are going to have to be brave enough to answer the question posed in my "2nd Update" if you want me to post the results. Otherwise, they'll be my secret. So, does a torque plate make a difference, or not, with this cylinder? By extension, whether or not it has an effect with this cylinder has implications for Gold Star and other similar cylinders.
Posted By: robcurrie

Re: 1928 Ariel Model C - 08/05/17 3:53 am

I predict that the bore will be smaller by .001" on the axis through the bolts. I also predict that when riding the 'bike across America, you would not notice it laughing

When I got my '62 AJS, I tore down the engine and took it to a friend that used to build our racing and rally car engines (he was also and old Brit biker in his youth). The engine had its original pistons that had the grooves enlarged to take metric rings, and the barrels had corrosion patches. We decided to go with a hone and I managed to find rings to fit from a BMW. I thought I might have to put up with a bit of piston slap and some smoking, but after five years of hard riding it doesn't smoke at all. A riding buddy has a Matchless with the same engine and fitted new pistons and had it nipping up until he took an extra 2 thou' more than the reccomended clearance, now it smokes.
Moral of the story is worn original beats modern wrong spec.

Rob C
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/05/17 3:41 pm

I finished the torque plate by countersinking with a 15/16" drill so the bolt heads would sit below the surface and there would be clearance for a 3/8BS socket to tighten them with a torque wrench.

The front and rear brake assemblies are nearly identical in design and each weighs 3.2 lbs.

I know I'm not alone in hating to backtrack, but yesterday I bit the bullet, disassembled the rear wheel axle and bearings, thoroughly cleaned all the "High Temp" grease from it (450 oF drop point), replaced it with Mobil 1 synthetic grease (550 oF), and reassembled. But, this time with the freshly refurbished brake backing plate. Also, I wasn't happy with the press fit of the oil seals so this time I carefully degreased the surfaces and used Yamabond as an additional aid to keep them in place. I snugged the bearings but then lightly tapped one end of the axle with a soft mallet, which resulted in some clearance developing that I removed by slightly tightening the nut. I repeated this process several times, alternating ends of the axle, until no further clearance appeared, at which point the bearings were fully seated.

There aren't all that many nuts, washers and spacers in the assembly, but more than enough to have been a nightmare had I not photographed it as I disassembled it. I pulled the photos for the wheel disassembly into Word for printing and they're now in the 'shop manual'.

p.s. Four months after this thread was started it now has the most views in this forum, passing a thread that started eight years ago. Who knew so many people were interested in reading about an old Ariel?...

Posted By: gavin eisler

Re: 1928 Ariel Model C - 08/05/17 5:27 pm

i am up for a guess, going for the torque plate closing the bore 2 tenths.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/05/17 6:05 pm

Originally Posted by robcurrie
I predict that the bore will be smaller by .001" on the axis through the bolts.
Originally Posted by gavin eisler
i am up for a guess, going for the torque plate closing the bore 2 tenths.
Well, after a few hundred views of the question, it looks like I'm going to have to count the above as an overwhelming response. Rob is closer, but Gavin wins according to the rules of the competition.

The answer to whether or not a torque plate has any effect, when it is bolted to the top surface of the muff with 30 ft.lbs it squishes the cylinder in by 0.0007" on the bolt-to-bolt axis and squishes it out by 0.0001" on the axis midway between the bolts. Applying the pressure directly to the protruding cylinder with a modified version of the pressure plate increases these two figures to 0.0009" and 0.0002" respectively. However, although the resolution of the bore gauge is +/-0.0001" I can't distinguish between these results within experimental resolution and repeatability. So, the effect is ~0.0008".

As Rob wrote, it's an old engine design and probably would work OK even with huge clearances, large amounts of wear, significant out-of-round, etc. However, since the piston clearance is ~0.005" this distortion is a ~15-20% effect, and it occurs near TDC where the combustion pressure is highest. Since I have the torque plate I'll certainly use it when doing the final honing to size. Also, based on these results, if I ever find myself needing to bore another Gold Star cylinder I'll definitely fabricate a torque plate for it as well.

What motivated me to make this plate in the first place was that for some years I've wondered if torque plates actually had a significant effect, or if they were mostly smoke and mirrors "knowingly" repeated by people without ever having actually checked. This was the first time since I started wondering about this that I was at a point where a cylinder would be bored.

Note that if anyone wants to question the results they'll have to make their own torque plate repeat the measurements on a 1928 Ariel cylinder. As for the winning prize... hmm, I hadn't thought that far ahead.
Posted By: gavin eisler

Re: 1928 Ariel Model C - 08/05/17 6:40 pm

No prize required, good game. Glad it was worthwhile. Great thread. Maybe recheck the measurements at running temps next.!
Posted By: robcurrie

Re: 1928 Ariel Model C - 08/05/17 7:52 pm

Well done Gavin. The only time we have ever used a torque plate was for reboring a 4 cylinder VW Golf (Rabbit in USA) engine for racing. The 'head is held down by stretch bolts torqued to 40nm then 60nm then 90 degree finally another 90 degree, so there is some serious force applied to the cylinder block over a non uniform area compared to a single cylinder with symmetrical bolts.

Rob C

Oh.... and the plate was 2 inches thick
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/06/17 3:37 am

Originally Posted by gavin eisler
Great thread.
Thanks very much. I'm applying everything I know, or think I know, about engines, bearings, machining, crack testing, etc. to this rebuild and not cutting corners even where it might not have any significant consequence. At the same time as dealing with a myriad of details, some at the level of 0.0001", I'm trying not to overlook the big items as well.

Originally Posted by gavin eisler
Maybe recheck the measurements at running temps next.!
Your '!' may mean you weren't serious, but I am. It happens that the cylinder will nicely fit in the oven I have in the garage that I will use for thermal expansion measurements on the pistons.

Frustratingly, today was a two steps forward, one step back day.

I put the cylinder aside until the pistons arrive and returned to the wheels. I'd already dealt with replacing the grease in the rear wheel with Mobil 1 Synthetic Grease so the only thing remaining to do with it was to put the complete assembly back on the bike. For the record, the total weight with tire, tube, and brake plate with new shoes is 36.2 lbs. Lifting the rear end quite high with the engine hoist I somehow managed to get the tire under the mudguard and back on the bike. Jeez, I sure hope I don't get a flat on this ride. But, it was progress.

I then raised the front of the bike, inserted some wood blocks under the frame to hold it at that height, and removed the front wheel. I had installed it, minus the brake, simply to support the front end (the rear was held up by the bike's stand). One it was off I thoroughly degreased the bearings and inside of the hub with MEK and acetone and repacked it with Mobil 1 grease. Everything went back together without issue, this time with the brake plate and again with Yamabond to help the seals stay in place, and I got the assembly back on the bike without extraordinary effort. Unfortunately, only at that point did I notice what I should have seen before, that the bead wasn't seated fully on the rim over ~20% of its circumference. After a number of attempts with a tire spoon, tire lube, ratcheting tie-down strap, and overpressure I could see no improvement and called it a day. Maybe it will fix itself overnight...

Since the bead has had a month to fix itself I'm not betting anything will change overnight. Trying to see the bright side, tomorrow I'll try a hot air gun to soften the rubber and if/when that doesn't work I'll wrestle the wheel off the bike again and get valuable practice using my tire changing tools in the hopes removing and replacing it -- without puncturing the tube, s'il vous plait! -- magically results in the bead seating all the way around. But, I don't want to practice with my tire changing tools(!), I just want the tire to be seated so I can be done with the wheels. Sigh...

Posted By: gavin eisler

Re: 1928 Ariel Model C - 08/06/17 11:43 am

Getting beads seated can be a PIA, I find the smoother the rim seat and the more lubed the rubber is then the better it goes, tyre fitters soap is best , at a push I have used Vaseline/ petroleum jelly in the past. Last time i re fitted rubber on my deep flange Borranis i spent an extra hour cleaning the rim / bead seat with scotchbrite back to shiny Alloy, the rubber seated with no real grief. It was much easier to refit .The old trick of deflating the tyre and bouncing it around sometimes works, re-inflate / deflate bounce, re-inflate, repeat till happy ( or disappointed).

I was semi joking about the up to temp measurements, a tricky job, made even trickier by the thermal gradient along the barrel when in service, the top end being bolted to a very hot thing and the bottom being bolted to a fairly warm thing when its running. My BSA has case temps around 55 c and head temps around 230 C when measured after a run.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/06/17 4:23 pm

Originally Posted by gavin eisler
Getting beads seated can be a PIA, ... repeat till happy ( or disappointed).
Indeed. I hate tires. Plan A this morning (once I steel myself for the task) will be to mark the "bad" section of tire and rim with tape in case I need the information for developing Plans B, C, ..., and try to lever it off the edge of the rim all the way around the wheel while it's still mounted on the bike. If I succeed in doing that I'll then squish it with the ratcheting tie down strap, slather it with plenty of tire soap, and hit it with a blast of air. Should that not work... well, let's not contemplate that just yet.

Originally Posted by gavin eisler
I was semi joking about the up to temp measurements, a tricky job, made even trickier by the thermal gradient along the barrel when in service,
I don't know how to predict what to expect, but the fact the torque plate only distorts the top inch or so of the cylinder is why uniform heating seems like a reasonable approach to seeing how it behaves. That is, my premise for trying this is if the top of the cylinder "doesn't care" what is going on more than an inch away then whether there is a gradient and the base is at 200 oC rather than 20 oC won't matter. Again, this indifference to temperature gradient is an operating premise, not a demonstrated fact.

Since I can't predict the result I can't tell you what I'll do with the information until I see it. It's easy enough to make the measurement, not even requiring me to remove the cylinder from the oven if I locate it with the top facing the door. At 100 oC the bore should increase by ~0.003" which is well within the range of the dial gauge. I'll set it to 0 at room temperature, let the cylinder cook for a few hours to get up to temperature, then open the oven and quickly measure the bore along the two axes before the tip of the bore gauge knows what hit it. That temperature should be high enough to tell me what might be happening under operating conditions, but not so high my bore gauge will be at risk.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/06/17 9:28 pm

The bead didn't seat itself overnight, and Plan A didn't work either. So, I got more practice with my expanded tire changing tool kit. I still hate changing tires but it's now significantly faster and easier.

I had marked the problem region of the rim and tire with tape and when I examined the rim I found what I had previously ignored as irrelevant. That is, the previous restorer had applied a heavy coat of paint to the rim while it was hanging from something and some of it ran to the low point and dried into fairly large "glops." There were glops elsewhere as well but, whether it's coincidental or not remains to be seen, the low point with the largest collection of large glops was where the tire refused to seat.

I mounted the rim on the mill with a steel brush in the chuck and, supplemented by another in a hand drill, I spent a half-hour smoothing the sides that the bead has to ride up as well as the flat surfaces where it is to sit. I then cleaned the inside of the rim surface, took it outside, mounted it in a drill press chuck, and hit it with a thin coat of etching primer as I spun it. I applied just enough primer to make the patches of bare metal disappear. Following directions I waited 30 min. and then hit it with a thin coat of gloss black enamel.

I won't know if this makes any difference at all until tomorrow because the directions say it takes 24 hours for the enamel to fully dry. I want to be sure there's a smooth low friction surface without any residual stickiness before re-mounting the tire so I'm not going to rush this. Fingers crossed that this was the problem and it is now fixed.
Posted By: kevin roberts

Re: 1928 Ariel Model C - 08/07/17 12:00 am

i use P80 and overpressure to seat the beads on my stuff. it's not failed me yet, but yours may be a unique enough situation to merit special attention.

this stuff is incredibly expensive-- usually twenty TEN bucks for 10ml. but i was looking for a picture to illustrate this post and found an entire quart of the stuff for sale on eBay for US$19.99. i bought it immediately.

so it sometimes comes up as a bargain.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/07/17 4:05 am

Originally Posted by kevin roberts
i use P80 ...
I'd never heard of the stuff before but it sounds quite useful. It comes in varieties with drying time from 20 min. to 2 hrs. Any of them sound like they'd be fine in the garage, but the 20 min. version seems best for the road. Which variety do you use?
Posted By: johnm

Re: 1928 Ariel Model C - 08/07/17 5:05 am

The 90/90 Avon race tyres are incredible difficult to get the bead to sit. I use over 50 psi. The Speedmaster style race tyre on the front of the KTT is also damn near impossible. I wont say what pressure my friends used but it was considerable more than 50 psi. Personally I'd find a way to sit behind a concrete wall while I did it !!!
Posted By: RPM

Re: 1928 Ariel Model C - 08/07/17 12:09 pm

Heating the cylinder in an oven will allow it to heat up evenly and expand accordingly. Going down the road at full operating temperature the cylinder will be hotter in some parts and cooler in others making the bore not so round in more than one place. It is the nature of the beast. I still say torque plate was a waste of time.

P80 is a great tool. I buy it from Coventry Spares and did not know they had different drying time formulas. The one I have seems to work every time I use it . I will see if it has a part number on bottle.

Avon race tires can be hell getting to bead up. We use the 130/650/18 rears and put well over 75 PSI ( or more ) in to get them to bead up. In the summer we would put the tire outside in the sun for a few hours before installing. I also remove the valve stem core when airing up stubborn tires to let the air in more quickly.

I got three big boxes back from Buchanan's on Friday so now I can figure out the wheel bearings to use. I am looking at some tapered roller bearing kits that are made for older flat tank bikes to replace the loose balls or just getting sealed ball bearings. The sealed bearings will need some spacers made and would be a little cheaper. The spokes are a little bigger than the old ones. I have to carefully drill out the special bolts that mount the brake pulley to each rear wheel.

Hope to get the 1915 back on the lift this week and rebuild gearbox. We want to take it to Davenport Swap meet at the end of the month.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/07/17 5:58 pm

Guys, guys, why didn't someone mention the problem of seating Avon tires when I was discussing the possible choices for this trip and before I bought them? Although I can quickly and easily fill tires to high pressure with my compressor in the garage, it will be a different story on the side of the road with a bicycle pump.

However, leaving tires and torque plates aside for the moment, let's turn to compression plates. At least two people have suggested this possibility for reducing the CR of a 7.5:1 piston to something more iron-engine friendly. I realized I may have been too quick to dismiss the suggestion because of its effect on rocker geometry since the adjusters are at the pushrod end of the rockers not at the valve end as they are on BSA and Triumph twin and triple heads.

I haven't yet measured the volume of the combustion chamber, but if I take 7.5:1 at face value as being accurate for the stock piston it means the volume of the head is 66.57 cc. Although 0.060" doesn't sound like much it increases the swept volume to 518 cc, in turn increasing the compression ratio to 7.78:1.

To decrease the compression of my 518 cc engine with a +60 nominal "7.5:1" piston to, say, 6.5:1 would require increasing the combustion chamber by 13.12 cc. This could be achieved with a compression plate of thickness 0.095" (2.41 mm).

After re-examining the rocker box it may be possible there is this much adjustment in the screws, in which case the geometry at the tip of the valves would remain unchanged. So, I shouldn't have been so quick to dismiss the suggestions of a compression plate. However, I'll have to do a test re-fitting of the cylinder, head, and rocker to see if there actually is that much available adjustment. If there isn't sufficient adjustment neither longer pushrods nor longer screws is an easy alternative because of their construction with mating hardened balls and cups.
Posted By: Alan_nc

Re: 1928 Ariel Model C - 08/07/17 8:52 pm

Tires/Wheels:

Coming in from way in left field here. Any chance of a second set of wheels with tires already mounted? And....following the left field thoughts....I know you are trying to be 'period' but Metzeler & Michelin both make tube type road tires in the size you need.
Posted By: Tridentman

Re: 1928 Ariel Model C - 08/08/17 2:52 am

Getting the tire bead to be concentric with the rim-----
I always use talcum powder on both the inside of the rim and the tire bead.
Pump up to about 70 psig and in 90% of the cases they are concentric.
The other 10%?--deflate, bump the tire on the ground several times rotating the wheel as you do it and then try again.
I have never had to bump the wheel more than once.
Number of tires fitted to wheels over 55 years of riding?
Hundreds---particularly when young and couldn't afford new tubes-- so had punctures 3 or 4 times a week.
HTH
Posted By: johnm

Re: 1928 Ariel Model C - 08/08/17 9:25 am

" Guys, guys, why didn't someone mention the problem of seating Avon tires when I was discussing the possible choices for this trip and before I bought them? Although I can quickly and easily fill tires to high pressure with my compressor in the garage, it will be a different story on the side of the road with a bicycle pump. "

I think you will be fine. Once they have gone on once things are much easier. And you would be pretty unlucky to get a puncture anyway unless the roads in the US have gone down hill a long way since I was last there.

And its the Avon race tyres that were the issue. Street tyres have never been a problem for me.
Posted By: RPM

Re: 1928 Ariel Model C - 08/08/17 12:32 pm

Yes Avon race tires can be tough to bead up. The street tires you are using do not seem to be very much trouble around here.

I would not run a compression plate just yet. If you check the compression ratio with fluid I think it will be lower than 7.78-1 or even 7.5-1. It seems to always be lower than what the piston manufacturers state.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/08/17 5:58 pm

Originally Posted by Alan_nc
Any chance of a second set of wheels with tires already mounted?
Even if it were possible to find a second set of wheels for a 1928 Ariel, having them wouldn't address the issue that worries me, of fixing a flat on the side of the road. Once back to the motel each day I can try to dragoon other people into helping me with the current wheels using all the tools they have at their disposal. On the road, I'm on my own.

Originally Posted by Tridentman
Getting the tire bead to be concentric with the rim...
I lubed, I strapped, I bumped, I overpressured, I seriously overpressured, I swore. Nothing worked. But, the last thing I did was to remove the tire and smooth the very rough surfaces that could have been the cause of too much sliding resistance for the bead.

Originally Posted by johnm
I think you will be fine. Once they have gone on once things are much easier.
Originally Posted by RPM
The street tires you are using do not seem to be very much trouble around here.
I hope you're right, but it will be a few days before I'll have a chance to check if that worked.

I should say that I am very happy with the upgraded tire changing tool set I've assembled (and practiced with). The fact the bead is being such a PITA is unrelated to the tools.

Originally Posted by johnm
And you would be pretty unlucky to get a puncture anyway unless the roads in the US have gone down hill a long way since I was last there.
Unfortunately, the roads have gone downhill over the past two decades. It used to be that, on average, roads in all industrialized nations I visited were pretty much comparable to ours. Some were a bit better (Sweden, quite a bit better), some a bit worse (although, not worse than Chicago). But now, again on average, our roads definitely have slipped to the condition in the next tier of countries.

Originally Posted by RPM
I would not run a compression plate just yet. If you check the compression ratio with fluid I think it will be lower than 7.78-1 or even 7.5-1. It seems to always be lower than what the piston manufacturers state.
I won't make that decision until after the piston arrives and I've measured the volume of its crown as well as that of the combustion chamber. My previous post was to show that it would be possible if needed, depending on the free length of the adjusting screws.

In that previous post I calculated that if I take the specifications at face value I would need a 0.095" compression plate to reduce a +60 "7.5:1" piston to 6.5:1. It turns out that [email protected] has the pattern for later Red Hunter engines cylinder bases, which are identical to mine, and he has on hand 0.094" (3/32") copper material. He custom makes these by CNC within a day so I should have it by the end of the week. Whether or not I use it will depend on the measurements I haven't made yet, but one thing gets crossed off the list knowing the option to take that path will be on the shelf waiting.

Even if I don't use it, it (and the JP piston) will be along for the ride in case they're needed on the ride. On the subject of JP pistons, they've confirmed that the rings they supply are cast iron.
Posted By: johnm

Re: 1928 Ariel Model C - 08/09/17 6:56 am

"Unfortunately, the roads have gone downhill over the past two decades"

Mmm. that's a surprise. The last roads in the US I tried were L.A. to San Francisco. Very nice trip.

For the past 4 years I have been in Eastern Europe and have destroyed two tyres on potholes. The worst - which has not happened to me - is when someone steals a manhole cover for scrap metal value. Imagine hitting that at 100 km/h.

My car is a Scoda Octavia 4WD station wagon. Basically a Czech Volkswagon. Really solid car and good in snow with snow tyres. Even though I destroyed two tyres hitting big holes the steering has never been misaligned.

49 years of driving and only ruined two tyres - both here - so perhaps even worse than Chicago !
Posted By: kevin roberts

Re: 1928 Ariel Model C - 08/09/17 10:10 pm

Originally Posted by Magnetoman
Originally Posted by kevin roberts
i use P80 ...
I'd never heard of the stuff before but it sounds quite useful. It comes in varieties with drying time from 20 min. to 2 hrs. Any of them sound like they'd be fine in the garage, but the 20 min. version seems best for the road. Which variety do you use?



i looked it up again-- the stuff sells on eBay for ten US dollars for a 10-ml squeeze tube:

[Linked Image]

this is what i use:

[Linked Image]

no specifications on the container, but the manufacturer is international products corp. the only two types i can find there are standard and food-contact formulations.

https://www.ipcol.com/assembly-lubricants/p80-emulsion

it's expensive, but like i said, search on it occasionally in eBay. i bought a quart there for US$19.99, and saved over 900 bucks.

better not be fake.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/10/17 4:22 am

Originally Posted by johnm
For the past 4 years I have been in Eastern Europe and have destroyed two tyres on potholes.
I just returned from a short trip to Los Angeles. Earlier today I drove to a house in the Hollywood hills on a very twisty series of streets where my speed in many places was limited by the condition of the streets, not by the twists and curves. I rounded one corner and hit a "ripple" in the concrete so high and deep that the car bottomed out.

After my visit Waze gave me the option of a longer, but faster route back to LAX with all but 3 miles of the 17 on city streets. Some stretches were fully "up" to Eastern European standards, and even the best stretches were no better than any of the streets I drove on in Russia in June (where the harsh winters have to be harder on the roads than the mild So. Calif. weather).

Originally Posted by kevin roberts
the only two types i can find there are standard and food-contact formulations.
The manufacturer's web site has a table showing six types, with drying times ranging from 20 min. to 2 hours:

https://www.ipcol.com/products/assembly-lubricants/

Originally Posted by kevin roberts
The stuff sells on eBay for ten US dollars for a 10-ml squeeze tube
It's always worth looking on Amazon.com because often products are less expensive there than on eBay. I just found it for $9.29 including shipping (although that isn't much of a savings in this case, it's still 70 cents).

There have been two new twists in the piston saga. When I arrived home the piston was waiting that I already had ordered from Draganfly before "discovering" the existence of the Omegas. Although Draganfly is clear that they supply several different brands, I assumed it would be a JP. It's a Gandini. So, now I have to research its reputation.

The other twist is offline someone said there have been reports of problems of partial seizures with Omegas when used in Ariels. I've asked for additional specific details. I note that when I ordered the Omega I was sent a scanned page from an old Ariel manual showing clearances, rather than anything issued by Omega itself. No matter what piston I use I'll need to know the proper clearance to keep it from seizing.

Meanwhile, "piston" moves from the 'problem solved' list back to the 'needs research' list. That's not progress. Sigh...
Posted By: johnm

Re: 1928 Ariel Model C - 08/10/17 5:51 am

" Some stretches were fully "up" to Eastern European standards "

Well I am surprised.

My own country, New Zealand, has slowly been improving our roads but the population density, country area, mountains and geology are not going to support a lot of motorway.

Much of the geology consists of young soft Tertiary sediments (especially in the North Island) and being on a major plate boundary there are plenty of earthquakes to keep the hillsides moving !!!

https://www.nzta.govt.nz/assets/pro.../kaikoura-earthquake-update-20170804.pdf

Posted By: kevin roberts

Re: 1928 Ariel Model C - 08/10/17 10:49 am

california is the same way. anywhere a highway crosses an active fault the road is patched-together like mad max
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/11/17 4:26 pm

Originally Posted by Magnetoman
offline someone said there have been reports of problems of partial seizures with Omegas when used in Ariels. I've asked for additional specific details. I note that when I ordered the Omega I was sent a scanned page from an old Ariel manual showing clearances, rather than anything issued by Omega itself
I've now heard from Omega. I supplied them with the details of the 1928 all-iron engine in which their piston would be used and they responded with the clearance they say is correct: 0.0037". If I didn't know any better and actually used this official clearance, piston seizure would be inevitable.

I had a long, ahem, boring talk with the now-retired machinist from my friend's shop (the guy who did the beautiful job piecing back together my Spitfire frame 20 years ago). He has bored countless motorcycle cylinders in his life and still does so part time. It happens that he bored the cylinders on the two Gold Stars that came to me via a deceased acquaintance.

He said that guy always had him bore cylinders 0.002" over the recommended size so there never would be a risk of seizure. He also said the only downside was there would be increased sound of piston slap on first startup until the piston quickly expanded into the much more slowly expanding cast iron cylinder. However, the additional noise isn't much since when my Aussie visitor rode the BB last fall he never complained about piston slap. Then again, he never complained about anything else during his visit...

An old Ariel manual recommends a clearance of 0.005"-0.007" at the extreme end of the skirt using the pistons of the time. As soon as the Omega piston arrives from England I'm going to make an appropriate jig, instrument them with thermocouples, and accurately measure the thermal expansion coefficients of it, the Gandini, and the Heplex/Hepolite. Based on what I find I'll properly correct for the value and aim for a bore giving 0.009" clearance. Or not, since in the process of reading everything I can find on the causes of piston seizure, lubrication is emerging as the real culprit, with insufficient clearance (i.e. seizure) the symptom not the cause.

Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/11/17 11:06 pm

The front tire fought me every step of the way but I finally got the bead seated.

When I first tried today a ~10" section again wouldn't seat, but it was a different section than before (I had marked the tire and the rim). Even ordering a tube of P-80 that won't be delivered for a week didn't cause it to seat immediately after I spent the $10 as one would have expected.

What finally worked was to deflate the tire and unseat the entire problem side. I then held the problem section of the tire with two tire spoons almost to the point of starting to remove the tire from the rim. At that point I added some pressure (requiring all three of my hands to accomplish this). As soon as the tube had sufficient air in it to push against the tire with some degree of force I pulled the spoons out, leaving the tube to keep the bead from slipping back toward the center. I quickly continued to add air. Whew.

It's not as if the wire brushing and painting did nothing. Staring with my first try today the bead on the opposite side of the tire completely seated once the pressure was high enough. Previously, there were ~10" sections on both sides of the tire that wouldn't seat. However, each time I released the air today I could hear the bead on the other side pop off the rim the as the pressure dropped. Each time I added air it would pop back on again.

I put 50 psi in the tire, one side fully seated and the other side all but 10", and put it into the sun to bake for an hour while I ran an errand. After I returned, this time when I released the pressure to add more soap and swear words the bead on the other side stayed in place instead of popping back off. So, fingers crossed, there's hope both sides of the tire will stretch enough that it will be possible to reinstall it, if necessary, without superhuman effort to get the beads to seat.

With the tire now on the wheel and the wheel on the bike I'll be taking a break from the Ariel until the Omega piston shows up. I have to be sure two of my Gold Stars are in shape for a ~1000 mile ride early this fall so I'll turn my attention to those bikes for a while.

p.s. The custom-made 0.093" copper compression plate I ordered just three days ago arrived in the mail today. It fits perfectly. If anyone needs something along these lines the company is:

Lani Visconti
Copper Gaskets Unlimited
[email protected]

As I wrote in an earlier post I don't know yet if I will use it. But, it's very nice to know I have it in case I do decide to use it. Even though there isn't much to the design it would have taken quite a while to machine such a plate myself on my manual mill.

Attached picture IMG_6644.JPG
Posted By: RPM

Re: 1928 Ariel Model C - 08/12/17 1:36 pm

The Norton using the JP pistons will be set up at 5 1/2 to 6. The 1915 was a little tighter but it uses the original cast iron piston. I would mention again about not using an oil control ring at the bottom groove.

Copper Gaskets Unlimited is a great company. Used them several times. Jack used to say " never fabricate something you can buy cheaper". That copper gasket certainly falls into that category.
Posted By: kevin roberts

Re: 1928 Ariel Model C - 08/12/17 3:50 pm

i use their stuff on my LSR machine, base gasket and rocker box. simple, re-useable, and high quality.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/14/17 1:34 am

Originally Posted by RPM
I would mention again about not using an oil control ring at the bottom groove.
Please explain why you say this. Is there a source(s) with information on this that you can point me to? I would greatly appreciate it. Thanks.

It's going to be two weeks before I get back to the Ariel. Meanwhile, the Omega piston arrived so the following are the weights of the complete assemblies (piston + rings + pin + circlips) of the three pistons I have for post 1935 500 cc Ariels (or, in my case, a 1928 Ariel with its connecting rod bushed down from 1" to 13/16" for the smaller gudgeon pin use in the later pistons).

Heplex (used) +40, 6.2:1
10793 cast inside
467.5 g

Omega +60, 7.5:1
6425.0.2 etched on crown
435.0 g

Gardini +60, 7.5:1
P810D-152 on box (only the bore in mm is etched on crown)
515.5 g

I measured all of these on a calibrated scale accurate to +/-0.5 g.

At present I have no idea how much the factory-original piston assembly with its 1" gudgeon pin weighed, nor the optimum balance factor to use. Knowing the former would allow me to calculate the balance factor used by the factory (assuming when I disassemble the crankcases I don't find "modern" machining marks indicating it has been altered). The reason this is very important can be seen from the following calculation.

As can be seen from my earlier post, there is a difference of 80.5 g (2.8 oz.) between the Omega and Gardini. If I pull a number out of the air for the weight of the small end of the rod (say, ~100 g, since it's very roughly the size of the gudgeon pin) in order to estimate the effect of this on the balance factor, it means the total weight to be balanced if the Omega were used would be:

435 g + ~100 g = 535 g.

If the balance factor with the Omega happened to be, say, 66% that means the weight balanced by the flywheel would be:

.66 x 535 = 353 g

Given this estimate, this means if instead the Gardini were substituted the balance factor would change to

353 g / (515.5 + ~100) g = 57%

Because this is a crude estimate the exact numbers aren't significant. What is significant is that this calculation shows the choice of these two aftermarket pistons would affect the balance factor by a very large amount. Clearly, such differences would have a significant effect on the vibration I will be subjected to for 4000 miles, which is why I'm spending the time required to try to get the balance factor "correct" rather than using some value pulled out of the air.
Posted By: KevinN

Re: 1928 Ariel Model C - 08/14/17 8:51 pm

Originally Posted by Magnetoman
Originally Posted by kevin roberts
some pictures of where you're at. dunno where you want to store them
Pictures of the entire rebuild await uploading from my computer once that problem is solved by Morgan or someone else.

Originally Posted by chaterlea25
Selecting material for the valve guides and some decent quality valves will enhance the reliability
Keeping road dirt away from the valve/ guide area will help a lot
I should be getting to the valves and springs before much longer. Unfortunately, I don't see any obvious way to enclose (or semi-enclose) the valve/guide area without degrading air flow to the cooling fins of the iron head. But, maybe once I start work on it I'll see a way to avoid dirt without affecting cooling.

Originally Posted by chaterlea25
In my experience decoking is not necessary after say 2000 miles (half way)
This is welcome news. It will save a lot of money (for a second piston) and time (taking off the head at the halfway point and discovering the 2nd head isn't needed). But, a new poster to this thread (KevinN) rode an old inlet-over-exhaust Harley in the previous Cannonball and wrote elsewhere that he decoked it every few days. KevinN, if you're still following this thread, was the decoking you did essential, or incidental to other work? Was the carbon buildup primarily around the exhaust port, which might be hotter than mine(?) because of the flathead design of that part of the head? RPM, did you have to decoke your Nortons?

On the subject of the piston, I've now made measurements of it and of the bore. I carefully calibrated my tenths-reading 3"-4" micrometer before starting, and used that micrometer to zero the bore gauge with its own tenths-reading dial, so the absolute and relative values of both are accurate to ~0.0001" (a tenth of a thou.) I'll just give representative data because I measured the piston and bore at the top, middle, and bottom and front-to-back as well as side-to-side so there is a lot of data.

For the piston clearance an old Hepolite sheet recommended 1 thou./in., for ~3 thou. total. For a Gold Star BSA recommended 2.5-4.5 thou. total for touring models and 4-6 thou for competition. Measured just above the bottom of the skirt from front-to-back the clearance of my Ariel's piston is 5.1 thou. when at the top of the cylinder and 4.4 thou. at the bottom. Side-to-side clearance is quite a bit more at 14 thou.

As for the rings, an old Ariel manual recommends 6-8 thou. end gap. Other recommendations are 3 or 4 thou./in. which would be 9-12 thou. What I found was the top compression ring was gapped at 22, the bottom at 25, and the oil ring at 26 thou.

The cylinder is round to within 0.2 thou. at the top and 0.3 thou. at the bottom. The cylinder tapers by ~0.7-0.8 thou. from top to bottom. Although vertical lines run from top to bottom around the entire circumference of the cylinder wall it feels glass-smooth to the touch. Either the rings were fully bedded in or it wasn't properly honed to begin with. I have to wonder if the vertical lines are due to the cylinder not having been thoroughly cleaned of abrasive after honing.

All in all, the piston and bore (but not the rings) are within reasonable spec, all things considered. From this data it seems the cylinder either was bored specifically for this 40-over piston, or it had been previously bored for a 40-over piston and the present one happened to fit "good enough". However, the piston is quite scuffed (i.e. vertical scratch lines), especially on the front and back faces but also to some extent near the bottom of the skirt on the sides as well, and nicked all over the top from bouncing something like a piece of broken piston ring. Unlike the lines on the cylinder wall, which are more like stains than scratches, the scratches on the piston are quite rough.

OK, from the above I can tell the previous rebuilder installed a very worn 40-over piston using too-wide ring gaps in a cylinder that had been bored to reasonable, although not precision, tolerance. If I had another 40-over piston on the shelf, which I don't, I could hit the cylinder with John Healy's favorite 180-grit hone and see if the clearance was OK-ish enough to use that piston. But, I don't have another piston of any size so it seems the only reasonable thing to do is look for a suitable 60-over piston and bore the cylinder to match.

One possibility to look for as a replacement is a similar "later" Ariel piston, although in 60-over. Although they don't have it in 6:1, Draganfly shows "excellent" stock levels for their 60-over 7.5:1 pistons for later Ariels, which are of an unspecified aftermarket brand. Everything I've found about aftermarket Ariel pistons says all of them are very heavy. So, one issue would be how much material I could remove from the skirt without weakening it, to minimize work on the flywheel to rebalance it to the best-guess balance factor. Similarly, how much I could remove from the crown to reduce the CR without weakening it. Or, would the iron head be able to deal with the extra heat generated by the higher compression? Comments and suggestions encouraged. Chaterlea25? Others?

While pondering the piston I got started making a torque plate from a piece of 6"-dia. x 3/4" steel. I've made quite a bit of progress with it but there is still a lot of metal to be removed to make the necessary ~3.5"-dia hole. Yes, I know, a torque plate might be overdoing things, but there's no reason not to the best job possible even if the improvement might be minimal.



MagMan,

Yes, I am following when I can. I'm only up to this point and haven't yet read any further. My iPad doesn't like this forum's editor, so I don't post here much, but in response to your questions, I rode a 1916 Indian in the 2016 Cannonball, not a Harley Davidson. It is a sidevalve engine, not IOE. I did not use oil control rings. I probably will use oil control rings in 2018, as several Indian riders did it successfully in 2016, proving that the automatic oiler can be adjusted to a low enough flow rate to accommodate the minimal oil usage that is experienced with oil rings installed. Note that it is a total loss oil system, it does not recirculate, so it is undesirable for the oiler to feed more than the engine burns and leaks. As I did not have time to test the automatic oiler's lower range of adjustment, I chose not to install oil rings last year. My oil consumption was by the book at one quart every 75 miles.

For the first half of the Cannonball I had to de-carbon the cylinders every few days. Since the Indian PowerPlus engine doesn't have removable heads, the normal procedure for de-carboning involves removing the cylinders and chipping the carbon out of the combustion chambers. To save time, I de-carboned through the valve plugs instead, using various long pointy tools, and sucked the carbon out with a vacuum cleaner. Either way, it's a tedious process. Some people say that ease of de-carboning was the reason that Indian transitioned to removeable heads on later engine designs.

Mid-way through the event, I started adding Sea Foam to my gas, and I didn't need to decarbon again after that. I should also mention that, at the same time, I started adding Marvel Mystery Oil to the gas to (successfully) remedy my sticky valves. Since I started adding both chemicals at the same time, I don't know which one fixed which symptom, but after that I didn't have to decarbon again, and my valves quit sticking.

I will mention that one rider who did not de-carbon, accumulated enough carbon in his combustion chamber for his piston to hit it, cracking the cylinder near the base flange.

I will also recommend running piston clearances and piston ring end gaps on the loose side for the Cannonball. Good luck!

I also want to mention that you can have pistons made in any size you want, no need to go .020 more oversized if you don't have to.


Kevin


.
Posted By: KevinN

Re: 1928 Ariel Model C - 08/14/17 9:27 pm

On the subject of seating beads, I have had good success mounting the wheel and running the bike up to about 70 mph. It's always worked for me. Wear a good crash helmet.




Kevin


.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/15/17 2:59 am

Originally Posted by KevinN
...I rode a 1916 Indian in the 2016 Cannonball, not a Harley Davidson. It is a sidevalve engine, not IOE.
Oops, I knew all that. I conflated your bike with my teammate's IOE Harley. Sorry.

Originally Posted by KevinN
I did not use oil control rings. I probably will use oil control rings in 2018, as several Indian riders did it successfully in 2016, proving that the automatic oiler can be adjusted to a low enough flow rate to accommodate the minimal oil usage that is experienced with oil rings installed. Note that it is a total loss oil system, it does not recirculate, so it is undesirable for the oiler to feed more than the engine burns and leaks. As I did not have time to test the automatic oiler's lower range of adjustment, I chose not to install oil rings last year.
This is very helpful. Thanks! It will take some riding experience to get completely comfortable with the Ariel's oiling system, but my present understanding is the excess gets spewed onto the chain. "Correct" oiling is a balance between enough mist in the crankcase to keep the cylinder oiled so the piston doesn't score, but not too much as to cause problems.

Originally Posted by KevinN
I started adding Marvel Mystery Oil to the gas to (successfully) remedy my sticky valves.
What mixing ratio did you use?

Originally Posted by KevinN
I will also recommend running piston clearances and piston ring end gaps on the loose side for the Cannonball.
Will do. I'm still trying to determine how loose to make those clearances, but they will be at the loose side of normal.

Originally Posted by KevinN
I also want to mention that you can have pistons made in any size you want, no need to go .020 more oversized if you don't have to.
Well, since I have two +60 pistons in hand now I'd like not to revisit that issue. It's "only" a matter of which one of those to use and the clearances. Oh, and the balance factor. The balance factor is an obstacle I've been working on for a couple of weeks now. If I only knew the weight of an original piston I'd know what to use. I have hopes just such a piston will magically appear next week.

Kevin, thanks very much for your valuable information. Feel free to keep following along, fighting the unfriendly interface, and posting additional comments as this rebuild moves along.

Posted By: RPM

Re: 1928 Ariel Model C - 08/15/17 12:17 pm

When I sent the 1915 Norton piston to Total Seal to have rings made the guy there told me not to use an oil control ring. It had been their experience in the past that is was better not to use an oil control ring on total loss oiling motors. I did not read it anywhere. Did the Aerial come with an oil control ring?
The 1915 Norton used less than a quart of oil each day on the Cannonball. Over oiling caused more problems than you would think. Made the motor run hot and slow. I do not like oil leaks and worked very hard to stop any leak we had so we lost very little to leaks.
A total loss oiling system is just what it says. The system is made to lose oil. Once the oil drips onto the crankshaft and rod journal that oil does nothing but stay in crankcase sump and get dirty. Very dirty. The crankshaft then throws that dirty oil around the inside of the motor and cylinder walls. I want to get rid of the dirty oil so out the tail pipe is a good place. On the Norton it lost some used oil via the engine breather but not much if the drip feed was set correctly.
Our rider saw quite a few others draining their sumps at each gas stop. Seems to me they were over oiling but since I never worked on a V Twin total loss oiling bike I really can not say that for sure. At the end of each day we would get about a 1/2 cup of oil out of the sump if the system was set up correctly.
We used Marvel Mystery oil in our gas. We would fill both tanks with race gas and add a a cap full of Marvel Mystery to each tank. When the rider would stop for gas he would turn on the auxiliary tank petcock and let it run into the main tank filling it about half way. Then he would top up both tanks. Allowing us to have better gas than what you would have straight from the pump.
I will try to pull the cylinder on the Norton this week and look at carbon build up.
Posted By: KevinN

Re: 1928 Ariel Model C - 08/15/17 12:24 pm

As far as the mixing ratio on the MMO, I wasn't very scientific about it, but I think it was only about 1 - 2 ounces each fill-up of about 2 gallons of gas. I know that some people are using two-cycle oil at about 200:1. The main thing is, side-valve engine need some kind of oil in the gas to lubricate the valve stems.

As far as balance factor, since the Indian only runs at a couple thousand RPMs on the highway, I chose not to sweat it too much. I measured the balance factor with the old pistons and determined it to be 58%, which was consistent with results that some others had reported on old Indians. With the new pistons the balance factor was somewhat high at about 69%, if I remember correctly. Essentially this means less imbalance up and down, but more fore and aft. It would have taken considerable drilling on my pristine, undrilled, original flywheels to reduce the balance factor back to 58%. I decided to assemble the engine and try it without drilling the flywheels, knowing that, based on the results I may have to open the engine back up and drill the flywheels. In the end, the engine ran very smoothly, and I've ridden it about 4000 miles that way. I know this is an emotional and widely misunderstood subject for many people, so I am not suggesting that anyone else follow my course of action in this regard, I'm just sharing my experience.

One more piont on oil rings - since there is no filtration, and since you obviously don't use/replace as much oil, you have to drain and refill the crankcase frequently, preferably at each fuel stop.



Kevin


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Posted By: gavin eisler

Re: 1928 Ariel Model C - 08/15/17 12:33 pm

"tuning for Speed" , by PE Irving page 59 on this PDF, talks about balance factors.
http://tuningforspeed.com/files/Tuning_for_Speed.pdf

if unknown he recommends 66 % as a starting point.
Posted By: kommando

Re: 1928 Ariel Model C - 08/15/17 1:43 pm

As long as it will hold up, I would go for the lightest piston at the recommended or best guess balance factor, if the reciprocating weight is at its lowest then there is less adverse effect from getting the balance factor wrong.
Posted By: RPM

Re: 1928 Ariel Model C - 08/15/17 2:45 pm

Originally Posted by KevinN
As far as the mixing ratio on the MMO, I wasn't very scientific about it, but I think it was only about 1 - 2 ounces each fill-up of about 2 gallons of gas. I know that some people are using two-cycle oil at about 200:1. The main thing is, side-valve engine need some kind of oil in the gas to lubricate the valve stems.

As far as balance factor, since the Indian only runs at a couple thousand RPMs on the highway, I chose not to sweat it too much. I measured the balance factor with the old pistons and determined it to be 58%, which was consistent with results that some others had reported on old Indians. With the new pistons the balance factor was somewhat high at about 69%, if I remember correctly. Essentially this means less imbalance up and down, but more fore and aft. It would have taken considerable drilling on my pristine, undrilled, original flywheels to reduce the balance factor back to 58%. I decided to assemble the engine and try it without drilling the flywheels, knowing that, based on the results I may have to open the engine back up and drill the flywheels. In the end, the engine ran very smoothly, and I've ridden it about 4000 miles that way. I know this is an emotional and widely misunderstood subject for many people, so I am not suggesting that anyone else follow my course of action in this regard, I'm just sharing my experience.

One more piont on oil rings - since there is no filtration, and since you obviously don't use/replace as much oil, you have to drain and refill the crankcase frequently, preferably at each fuel stop.



Kevin


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I do not understand the refilling part. On the Norton it drips on the crankshaft and then goes away. The crankshaft does not have an oil slinger like on some old motors and should not ride in the oil that is in the sump. As the oil drips on crankshaft it slings the new oil everywhere inside. I drain the sump and go.
Posted By: KevinN

Re: 1928 Ariel Model C - 08/15/17 3:09 pm

Originally Posted by RPM


I do not understand the refilling part. On the Norton it drips on the crankshaft and then goes away. The crankshaft does not have an oil slinger like on some old motors and should not ride in the oil that is in the sump. As the oil drips on crankshaft it slings the new oil everywhere inside. I drain the sump and go.



That's OK RPM, I'll explain; early Indians hold about 4 or 5 ounces of oil in the sump, which the flywheels sling to the cylinders and other areas. The oil level is replenished by an adjustable reciprocating pump called an automatic oiler, and supplemental oil is provided by a hand pump. When the sump is drained, the level must be returned to the middle of the site glass by use of the hand pump. I apologize if this information isn't applicable to the discussion, I don't have experience with this particular model of motorcycle. Just offering what I can, didn't mean to muddy the waters.



Kevin


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Posted By: RPM

Re: 1928 Ariel Model C - 08/16/17 12:06 am

So once again I was confused. The Norton and Indian do it different. I bet the Ariel has a different system also.
We ran Valvoline VR1 50wt oil and no additives.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/16/17 12:47 am

Originally Posted by RPM
When I sent the 1915 Norton piston to Total Seal to have rings made the guy there told me not to use an oil control ring. It had been their experience in the past that is was better not to use an oil control ring on total loss oiling motors. I did not read it anywhere. Did the Aerial come with an oil control ring?
The 1928 pistons only had two rings but sometime a decade later they added an oil ring without simultaneously making any changes in the oiling system. Apparently Ariel's thinking on oil control rings changed in the 1930s.

I certainly give more weight to manufacturers' recommendations than to random suggestions, but only if they makes sense. As I wrote previously, I gave Omega the information that I would be using their piston in an all-iron 1928 motorcycle engine and the guy who responded recommended a gap of 0.0037". Unless I un-expectantly find their alloy behaves significantly different than do other Al alloys when I measure the thermal expansion, I will not be following their recommendation because it makes no sense for my engine.

It seems to me there are two distinct aspects to the issue of an oil ring: what goes on from the crankcase up to the top of the rings, and what goes on above the rings.

Starting at the bottom, the cylinder walls need oil on them to keep the piston from scuffing. However, this is completely independent of whether or not the valves and guides are bathed in oil. If an oil ring doesn't somehow scrape so much oil off the wall that it causes problems with the piston in a, say, Gold Star, it won't cause problems in a total loss motorcycle either. Unless the amount of oil flying around in the crankcase is so marginal that it's near the limit of being adequate for the piston.

Next is the combustion chamber. Ideally, it should be completely free of oil since even a small amount reduces the octane of the fuel.

Finally, if oil is needed to help lubricate the valves there are two ways of arranging for it. One is to leave the oil ring off, although there are several downsides to that. First, the amount of oil that gets past the compression rings is unpredictable. If too much gets by you'll be de-coking the top end frequently, as Kevin had to do early in his ride. If too little gets by the guides will wear. The other choice is to put an oil ring on to help keep the oil in the bottom end of the engine where it belongs and separately arrange for valve lubrication with Marvel Mystery Oil in the fuel.

Originally Posted by RPM
The 1915 Norton used less than a quart of oil each day on the Cannonball. ... Once the oil drips onto the crankshaft and rod journal that oil does nothing but stay in crankcase sump and get dirty. Very dirty. ... Our rider saw quite a few others draining their sumps at each gas stop.
The Ariel owners guide calls for draining the sump every 1000 miles. There are two outlets (breathers?), one halfway up the crankcase and the other from the timing chest. However, I won't understand the oiling system until I open the crankcases because the descriptions of the system are anything but comprehensive. I'll be revisiting this issue later.

My Ariel is supposed to be fed 10-15 drops/minute. Since according to google there are ~19,000 drops in a quart that's equivalent to ~19000/15 = 21 hours of riding, or ~750 miles at 35 mph. Basically that's a third of your oil consumption.

Originally Posted by RPM
We used ... a cap full of Marvel Mystery to each tank.
Originally Posted by KevinN
As far as the mixing ratio on the MMO, I wasn't very scientific about it, but I think it was only about 1 - 2 ounces each fill-up of about 2 gallons of gas. I know that some people are using two-cycle oil at about 200:1.
Thanks guys. Ariel calls for an "egg cup" worth of oil to be added to each gallon of fuel to lubricate the inlet valve. Depending on the volume of Medieval (1928) English eggs, that corresponds to something in the range 100-200:1.

Originally Posted by KevinN
As far as balance factor ... I know this is an emotional and widely misunderstood subject for many people,
Indeed. A couple of reactions I got off line were as if I had asked them their bank balance rather than their balance factor.

Originally Posted by KevinN
since the Indian only runs at a couple thousand RPMs on the highway, I chose not to sweat it too much.
I haven't given up yet, but if the needed information isn't unearthed in the next two months I may have to take my best guess and hope for the best.

Originally Posted by gavin eisler
if unknown he recommends 66 % as a starting point.
Thank you, but I'm still hoping to start with the ending point. Testing to find the optimum balance factor for my Ariel would be best. However, to find optimum that way would require me to remove the engine, disassemble, rebalance and rebuild, reinstall, road test at various speeds, and repeat that process a half-dozen times. Call me lazy, but I don't want to do that. I'm willing to settle for the balance factor the factory used in 1928, but to determine that I need the weight of a 1928 piston.

Originally Posted by kommando
As long as it will hold up, I would go for the lightest piston ...
That's an excellent point. In the limit of a zero-weight piston (and rod) the engine could be balanced to be as vibration-free as an electric motor, so lighter is better all other things being equal (which they may not be...).

The balance factor remains the biggest unknown at the moment, but I'm still open to technical information on whether or not to use an oil ring. As of now I'm in the pro-ring camp. But, given its importance, this isn't the last readers of this thread will hear of oil regulation, oiling issues, oil rings, etc.
Posted By: Richard Kal

Re: 1928 Ariel Model C - 08/16/17 4:31 am

"The 1928 pistons only had two rings but sometime a decade later they added an oil ring without simultaneously making any changes in the oiling system. Apparently Ariel's thinking on oil control rings changed in the 1930s."

There is (or needs to be) a web (a baffle) across the mouth of each crankcase half. When the cases are assembled, there is just enough clearance for the rod to reciprocate. The baffling will prevent excess oil from the flywheels being thrown onto the piston skirt; necessary because of the lack of an oil ring. I suspect they also influence pressurisation and oil mist movement between the underneath of the piston, and the flywheels. I have been told by an old timer that some tuners would remove the baffling, but due to a lack of understanding I am not advocating this.

There are two plate type check valves pressed into the inner wall of the timing chest (RH crankcase). They will allow oil mist to pass from the crankcase cavity into the timing chest, but not the other way.

From the factory operator's handbook, the timing gear cavity must contain quarter of a pint of oil before start-up (filled through the plug near the top of the outer timing case; say at 1 o'çlock)'.

To assist in priming the oil pump, it is handy to tap the banjo in the feed pipe into lower part of the outer timing case (approx 7 o'çlock) and fit a 1/4" screw (sealed with a fibre washer). Easy to access.

In 1929 the Black Ariel lubrication system was upgraded to dry sump (the oil pump was upgraded from single stage, to the familiar two stage piston type (addition of the scavenge section).

I don't know when they added the oil control ring, but it would have become necessary as the oiling system evolved (higher circulation rate).

Richard

Posted By: KevinN

Re: 1928 Ariel Model C - 08/16/17 12:45 pm

I think your on the right track with the oil ring issue, MM. Based on my Cannonball experience, crankcase oil is not a very effective valve lubricant, as evidenced by the fact that I was consuming a quart every 75 miles and my valves were still sticking terribly, until I started adding the MMO to my gas. They were sticking to the point that I was on the side of the road for an hour and a half one day with stuck valves. After the engine cooled down, I was able to unstick the valves on one cylinder and finish the day's ride that way. Not only was the MMO effective in lubricating the valve guides, but it prevented the motor oil from gumming up the valve guides. Like RPM, I was also using Valvoline VR1 50w motor oil in 2016.

To me, the issue of adding oil rings to an engine that did not originally have oil rings comes down to two things:

1- you must be able to reduce the goesinta so that it still equals the goesouta's. The goesinta being the oil that is supplied to the engine, whether by pump, drip, or other method, and the goesouta's being the sum total of leakage, plus mist exiting the crankcase breather, plus oil consumed in the combustion chamber (which will now be greatly reduced).

2- The new (reduced) goesinta flow rate must be adequate to lubricate everything that needs to be lubricated.



I sure would like to see some pictures!


Kevin #97


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/16/17 4:40 pm

Originally Posted by Richard Kal
There is (or needs to be) a web (a baffle) across the mouth of each crankcase half. When the cases are assembled, there is just enough clearance for the rod to reciprocate. The baffling will prevent excess oil from the flywheels being thrown onto the piston skirt; necessary because of the lack of an oil ring.
Hmm, the plot thickens. Thanks very much for pointing this out. I hadn't yet done anything with the bottom end other than make a stand to hold the crankcases. Indeed, cast into each crankcase half are horizontal plates near the top leaving a slot ~3/4" wide for the rod but blocking all but slivers of the inner edges of the flywheels.

Originally Posted by Richard Kal
To assist in priming the oil pump, it is handy to tap the banjo in the feed pipe into lower part of the outer timing case (approx 7 o'çlock) and fit a 1/4" screw (sealed with a fibre washer). Easy to access.
Can you expand on this a little? The oil feed system for '28 is a little different than '27 (and, possibly, early '28(?)). My oil system operates on vacuum with the screw in the sight glass used to bleed air into the system, reducing the vacuum/suction, thereby reducing the oil flow. Anyway, because of this, it's not clear to me how a bleed screw at the bottom of the feed pipe would help prime the pump. If I opened such a screw it wouldn't result in oil flowing from the tank to displace air in the tube and fill it with oil because first the oil in the tank has to be sucked up into the sight glass on top of the tank before it then drops into the pipe.

Originally Posted by Richard Kal
I don't know when they added the oil control ring, but it would have become necessary as the oiling system evolved (higher circulation rate).
As far as I could tell from the information I can find is the oil ring was added some time after the oil pump was upgraded. But, the information is sketchy so I'm not sure of this.

Originally Posted by KevinN
Like RPM, I was also using Valvoline VR1 50w motor oil in 2016.
What are your thoughts on using AeroShell "ashless" oil? Did anyone use this oil, and why or why not?

Originally Posted by KevinN
1- you must be able to reduce the goesinta so that it still equals the goesouta's. ...
What I won't understand until I take the bottom end apart is how those two outlets from my engine (from the crankcase and the timing chest) function. That is, is the oil system designed so that once the levels in the crankcase and timing chest reach steady state does every extra drop of oil that reaches the crankcase cause a drop to leave one of those pipes and fall on the road? If so, to some extent old, used oil will be continuously flushed from the system by new oil.

Originally Posted by KevinN
I sure would like to see some pictures!
I'd be happy to post pictures. I just need to find the time to figure out a workable, long term solution to the problem of hosting photos so I can insert them where they belong in each post and not lumped as attachments at the end.
Posted By: chaterlea25

Re: 1928 Ariel Model C - 08/16/17 11:14 pm

Hi All,
Quote
There is (or needs to be) a web (a baffle) across the mouth of each crankcase half. When the cases are assembled, there is just enough clearance for the rod to reciprocate. The baffling will prevent excess oil from the flywheels being thrown onto the piston skirt; necessary because of the lack of an oil ring.


Not completely accurate

Some engines have baffles and run oil rings, (Indian Chief)
Some V twins have baffles only on the rear cylinder, (BSA), originally no oil rings
MM's Ariel single has baffles, originally no oil ring
Rudge's both total loss oiling and dry sump do not have baffles or oil rings originally

Designers back then tried many and various things in attempting to better the breed !
A few went off and started with a clean sheet and fresh thinking, mostly they failed commercially as potential customers were reluctant to spend on untried ideas

To the best of my knowledge lip oil seals for instance, which would have greatly improved early engines and gearboxes came into being in the forties
The lack of effective sealing meant that oil volumes / circulating capacities had to be kept low

Ariel only went to fitting oil rings when they enlarged the feed pump plunger diamater to 1/4in. (my 39 350 had the smaller pump)

The two 29 black Ariels local to me are running the late 50's pumps, (increased from 1/4in.)
One is running a BSA piston with oil ring , I do not know about the other only that fitting the larger capacity pump has not caused any problems

John


Posted By: KevinN

Re: 1928 Ariel Model C - 08/17/17 2:57 am

You asked about Aeroshell ashless MM. I'm sure it's good oil. I think some Cannonballers are using it. My only personal experience with it is in airplane engines with recirculating oil systems and oil rings. The price isn't totally ridiculous by today's standards, if I recall correctly. I don't always recall correctly though...




Kevin


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/17/17 4:15 am

Originally Posted by KevinN
You asked about Aeroshell ashless...The price isn't totally ridiculous by today's standards, if I recall correctly.
On Amazon.com a 12-qt. case of the Valvoline VR1 you and RPM used is $46 delivered and AeroShell W100 Plus (SAE 50 with additional antiwear additives not in W100) is $115. If my Ariel actually ends up using 1 qt./750 miles as per the calculation in my previous post it would go through ~ 6 qts. on the trip so the AeroShell would cost ~$35 more than if I used Valvoline. If the "ashless" properties reduced the chances of having to decoke the engine, and even if it used 3x that amount of oil, it would be money well spent.

We got an email from the organizers yesterday saying they're still working on the route but suggest we buy National Park Senior Passes since we will go through two National Parks on the route which otherwise would cost $35 per vehicle (n.b. whether one person on a motorcycle or a dozen people in a car it requires one pass holder per vehicle). The lifetime passes are $10 now but will rise to $80 on Aug. 28 for those of you 62 or older interested in this bargain (I already have one), whether or not you will have anything to do with the Cannonball.

Anyway, as a result of this email we now know three locations on the route in addition to the end points, i.e. Sturgis SD, Badlands and Glacier. I'm guessing from this that we'll be making a swooping mirrored 'S' curve across the U.S., passing below Chicago at the furthest south, and nearly reaching the Canadian border at Glacier at the furthest north.

If they take us over the Continental Divide via Logan Pass in the park the maximum altitude we will reach on the rally will be 6,647 ft. That route is closed in winter, and September is pretty close to winter that far north, so it will be chilly. Also, I found that the maximum wind speed recorded on that pass was 139 mph so it could be difficult making forward progress with bikes having top speeds only half that.

Posted By: RPM

Re: 1928 Ariel Model C - 08/18/17 12:27 am

I have never tried the shell oil. We have been using Valvoline forever and it seems to work.
When Ariel wrote the manual in 1928 what was the average speed on UK roads back then? On the Cannonball you will be riding 50 plus mile stretches at 50 to 55 mph ,maybe more. No where in the UK could you have done this in 1928. The oil consumption will be more on the Cannonball than the manual states I think. Who cares as long as you make every mile.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/18/17 5:54 am

Originally Posted by RPM
I have never tried the shell oil. We have been using Valvoline forever and it seems to work.
I'm of the school that any oil is way better than no oil. However, what draws me to AeroShell is their claim that "The non-ash forming, polymeric additive was developed to help eliminate the harmful combustion chamber deposits that occur during normal operation... These additives leave no metallic ash residues that can lead to deposit formation in combustion chambers and on spark plugs, which can cause pre-ignition and possible engine failure."

AeroShell is non-detergent, using dispersants not detergents to break up insoluble contaminants and keep them suspended, and not recommended for automotive engines, no doubt because it contains additives harmful to catalytic converters ("This [additive] protection helps keep the camshaft and lifters coated, reducing the likelihood of premature damage..." Although Valvoline calls VR-1 a "racing oil" it is approved for street use and, consistent with this, has zinc and phosphorous levels essentially the same as "standard" oils.

But, whether or not the additional additives in AeroShell are needed for the cams and lifters in our old engines it's not that, but the hope of reduced carbon buildup that attracts me to AeroShell. Note: for anyone else considering using this oil, Shell says not to use if for break in. For that I plan to use a quart of Lucas 30W Racing Break-In Oil.
Posted By: kommando

Re: 1928 Ariel Model C - 08/18/17 8:50 am

The additive harmful to Cats will most likely be ZDDP which protects cams and sliding lifters. No harm in having good levels of that as long as no Cat is fitted.
Posted By: KevinN

Re: 1928 Ariel Model C - 08/18/17 12:55 pm

I have a policy of not participating in oil threads... too emotional for me. ;-)




Kevin


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/18/17 4:40 pm

Originally Posted by KevinN
I have a policy of not participating in oil threads... too emotional for me.
I can't fault your position on this, since it has been mine as well. Judging from the the oil threads I've seen everyone has an opinion. I just thought AeroShell might be different enough that it was worth mentioning in case anyone was aware of actual facts to indicate I shouldn't use it. But, upon reflection, it's probably best to move on to a different topic.
Posted By: RPM

Re: 1928 Ariel Model C - 08/24/17 12:10 am

Link to photos of carbon build up after about 4k miles on 1915 Norton. First time to pull top end. Only way I know to post photos.

https://www.facebook.com/Big-D-Cycle-190119784358276/

Not bad I think. Going to put it back together. Go to Davenport Swapmeet and seek looks of admiration as we like to say. Can check new gearbox parts while riding it around.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/28/17 4:16 pm

Last week I had the opportunity to make a number of measurements of the temperatures of heads (near the inlet and the exhaust), cylinder tops, and cylinder bases of ten all-iron engines immediately after they pulled in after reasonably fast runs.

I also learned last week that common practice among at least one large group of Irishmen is to use chain lube on the valve stems, with one shot every ~150 miles ("if I remember"). Although they say this works OK, none of them put hundreds of miles/day, day after day, on their bikes.

The ideal properties of a grease for this purpose is one that melts by ~250 oF (i.e. actually melts, not separates into thin oil and fillers), clings to the oscillating surfaces at up to ~450 oF despite being in the liquid state (although, based on my measurements, ~375-400 oF max. seems more likely for my Ariel), and congeals when it cools without the components having separated. Thanks to the results of a scientific collaboration with chaterlea25 last week I now will be using a rocker-box grease for vintage open-valve aircraft engines as my valve stem lubricant. I expect it should be a bit better for this purpose than chain lube.
Posted By: gREgg-K

Re: 1928 Ariel Model C - 08/28/17 7:10 pm

Originally Posted by Magnetoman
<SNIP>Thanks to the results of a scientific collaboration with chaterlea25 last week I now will be using a rocker-box grease for vintage open-valve aircraft engines as my valve stem lubricant. I expect it should be a bit better for this purpose than chain lube.

This rocker box grease sounds like a great find, which I would benefit from as well.

MM, where would I be able to buy some of this grease? I've been planning to run some 2-stroke oil in my fuel, but this sounds even better.

Thanks,
... Gregg
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/29/17 1:46 pm

Originally Posted by gREgg-K
where would I be able to buy some of this grease?
To be clear, I am not recommending or un-recommending this grease, only saying that based on my own IR temperature measurements, the grease's specifications, and my observation of the behavior of the grease on a small number of iron-head engines over a limited number of miles, I will be using it myself. I disavow all responsibility if anyone else uses it and is dissatisfied for any reason. That said, it's:

http://www.jewellamberoil.com/

As you will see the oil/grease is available in cartridges for either grease or caulking guns although, as the web site explains, it is basically thick oil, not solid grease, so it will ooze out of a standard grease gun. Even before last week's tests I had modified two grease guns to use it.

For a full-size, 14 oz. gun I machined a replacement plunger with two O-rings ea. on the OD and ID and filled the gun from a caulking-type cartridge. Further, I cut one turn off the spring to reduce the pressure on the grease to decrease the chances of it being slowly forced out past the O-rings. Note: I modified a grease gun made with an extruded Al rather than a welded steel tube to give the O-rings a smooth round surface to seal against, and I polished the plunger rod with very fine abrasive paper, again to give the O-rings a smooth surface.

For a small, 3 oz. gun with a needle tip to reach between the coils to the valve stems, I machined a plunger with two O-rings and blind tapped for a length of 1/4" all thread with a palm pad to allow me to manually push against the plunger to take up the free space. This one will be along for the ride every day.

In addition to using this grease on the rocker components I'll mix a bit of 2-stroke oil in the gasoline (~200:1 or so) as Ariel originally recommended for helping with the inlet valve.


Attached picture IMG_5364.JPG
Attached picture IMG_5367.JPG
Posted By: Magnetoman

Re: 1928 Ariel Model C - 08/30/17 10:42 pm

Although I need to be spending time with two other bikes I put the front wheel back on the Ariel today so the "only" things left to do are to rebuild the engine and gearbox...

There is no carbon buildup anywhere on the piston or head so the engine has had very few miles put on it since the rebuild, i.e. it's in the condition the rebuilder left it. For rings to seat a 150-180 grit hone has to be used, which leaves a surface roughness of 0.8-1.2 microns. The other thing I did to it today was to measure the roughness of the cylinder wall to be 0.51 microns which, if a cross-hatch pattern were visible (which it isn't), it would have been made with a 320-400 grit stone. The too-smooth surface means the rings never would have seated, and the absence of hone marks means the rebuilder assembled the engine without even honing it with stones that were too fine.

Anyway, the smoothness of the cylinder wall again vindicates my decision to completely rebuild the bike. I hope no horrors await me as I dig deeper into the engine. But, first, the other two bikes.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/02/17 11:07 pm

Without knowing the weight of the original piston assembly I would have to guess at the balance factor, almost certainly resulting in more vibration than if I had the right number. So, over the past two months I've posed my question about the weight here, on the owners club website, to Black Ariel specialists and people who own the same machine, etc. as well as followed every lead given to me. But, without success.

The Yahoo Ariel forum has fairly low traffic (although, higher than Britbike's Ariel forum) but I realized today I hadn't asked my question there. Not having much hope it would lead anywhere, I posted my question. Less than three hours later I had the answer to within 0.1 gram from a fellow owner of a 1928 Ariel in Auckland(!).

Having this weight is a big step forward in the rebuild since the balance factor was the only known unknown. Of course, unknown unknowns could ambush me at any time before the fat lady sings.
Posted By: old mule

Re: 1928 Ariel Model C - 09/03/17 2:26 pm

This Ariel tale here is the best thing on the motorcycle internet, in my opinion. Thanks for taking the time to document your work!
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/03/17 4:02 pm

Originally Posted by old mule
This Ariel tale here is the best thing on the motorcycle internet
Thanks very much. But, if you think it's good, think of how much better it would be if Morgan could solve the issue with images...

In what follows I'll carry the weights to 0.1 g although the actual uncertainty of the total is at least 1 g. My new friend in NZ reported the following:

piston 348.2 g / 12.28 oz.
gudgeon 94.4 g / 3.33 oz.
aluminium gudgeon caps 32.0 g / 1.13 oz.
rings (not weighed) TBD

The two compression rings in my Heplex piston weigh 16.0 g so the total weight of the original piston assembly would be 490.6 g if its rings are the same as mine.

The density of bearing bronze is a little higher than that of steel (8.9 g/cc vs. 7.8-8.1 g/cc), resulting in the weight of the reducing bushing in the small end of my Ariel's rod being 8.3 g heavier than that of the stock bushing. Adding this 8.3 g, the comparable weights of the two aftermarket +60 7.5:1 pistons are:

Omega 475.8 g (underweight by 14.8 g / 0.52 oz.)
stock 490.6 g
Gardini 523.8 g (overweight by 33.2 g / 1.2 oz.)

As a simple calculation to show why I've been so concerned with this, an extra 1 oz. rotating at 4000 rpm at the edge of an 8"-dia. flywheel results in an additional 114 lbs. of oscillating force. Hence, Ben Franklin's famous observation that an ounce of piston is worth a 100 pounds of cure.

This force scales as the square of rpm so it becomes 178 lbs. at 5000 rpm. Taking it to the limit, the redline of my engine is ~5500 rpm so if I simply installed the Gardini piston the additional vibrating force would be an eyeball bouncing 258 lbs. unless I had rebalanced the flywheels for it.

If I get the flywheels within 2 g of the "correct" factory value, the 3100 rpm my present gearing will give at the Cannonball's max. speed (I hope) of 50 mph will result in an additional oscillating force of 5 lbs. beyond that which an engine balanced to factory specs. would have had. That's not to say a single can be balanced perfectly no matter what, nor that I'm assuming the factory found the ideal compromise in the first place, but at least I now can take advantage of the results of their testing since I can't build and rebuild the engine a number of times to do my own testing.

Thanks to now knowing the total weight of an original piston to within ~1 g I will be able to properly balance my engine to as it was when it left the factory. However, since the balance factor includes the weight of the small end of the rod I won't be able to determine the figure until I disassemble the rest of the engine and put it on rollers and a scale. My rollers have a sensitivity of 0.09 oz-in., which is equivalent to 0.6 g at the 4" radius of the flywheels.

Posted By: gavin eisler

Re: 1928 Ariel Model C - 09/04/17 10:50 am

Can we have a new competition? Guess the original balance factor as found to match original piston weight? I will shoot for 52%.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/04/17 2:39 pm

Originally Posted by gavin eisler
Can we have a new competition? Guess the original balance factor as found to match original piston weight? I will shoot for 52%.
That's an excellent idea. However, if I can offer a friendly amendment, the number has to be accompanied by a short, plausible explanation. As a hypothetical example, "52%, because that's what was used on a 441 Victor." The reason given doesn't have to be correct (e.g. even assuming 52% had been used on it, the 441 mounts its engine in a swinging arm frame), just not totally off the wall.

The contest you suggest is based on the realistic scenario I was facing. Had I not been able to find the weight of the piston to enable me to calculate the original balance factor, I would have had to make an informed guess based on plausible reasons.
Posted By: kommando

Re: 1928 Ariel Model C - 09/04/17 3:05 pm

65% based on front down tube angle
Posted By: gavin eisler

Re: 1928 Ariel Model C - 09/04/17 3:38 pm

Ok, 52% based on relatively low revving motor, sweet spot 3K.
Posted By: robcurrie

Re: 1928 Ariel Model C - 09/04/17 5:26 pm

60% ....my highest math score

Rob C
Posted By: KevinN

Re: 1928 Ariel Model C - 09/05/17 12:30 pm

I would have said 52%, but Gavin beat me to it. The reason is that it is a common balance factor used on old motorcycles, in my limited experience.




Kevin


.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/05/17 11:11 pm

To further seed the contest, a 1960 BSA Service Bulletin shows 60% for the 250cc 'C' series, 58% for Gold Stars, 55% for the essentially identical 'B' series in the same frame as the Gold Star, and 55% for both the 500cc and 650cc 'A' series twins, also in the same frame as the Gold Star.


Addendum: In 'Tuning for Speed' Phil Vincent wrote "... the Speedway Vincent engine with standard 66 per cent factor caused severe vibration in a very light dirt-track frame until the factor was reduced to 61 percent, a matter of 1.3 oz. at pin radius." Note that the Gardini Ariel piston is 1.2 oz. different than the stock piston. Assuming the internal weights of the 500cc Vincent engine are roughly the same as for the 500cc Ariel engine this means that, unless the flywheels were rebalanced, this difference in weight would move the balance factor by ~5% from the value the factory decided it should have. At least for the special Vincent frame, a 5% change was enough to have a large effect on the vibration.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/06/17 4:31 pm

My new Ariel best friend in NZ found his original rings and weighed them. They are roughly double the weight of a pair of modern rings (32.6 g vs. 16.0g), which makes a significant difference in the total weight of the piston assembly.

As I mentioned in an earlier post, my rollers have a sensitivity of 0.09 oz-in. Since the weights hang off the crankpin, this is equivalent to 0.17 oz (4.8 g) at the 1.87" radius of the throw. Again assuming the internals are similar to the Vincent's, this corresponds to being able to determine the current balance factor to within +/-0.6% of its actual value, and then hit that value again with a new piston (the errors add so the final value would be within +/-0.85%).

To be clear, I've listed percentages, not percentages of percentages. So, for example, if the current balance factor of my engine were, say, exactly 50.0%, the "+/-0.6%" sensitivity of the rollers for this particular configuration would result in me determining a value somewhere between 49.4% and 50.6%.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/08/17 4:19 pm

Trust can be an expensive thing to lose. Specifically, losing trust can cost $131.54 (plus shipping and several hours of my labor).

Although I've been working on my Catalina the past week, every time I walk by the Ariel engine on the bench I look at the bushing in the small end and wonder. It looks good, and has the color of bronze, but is it an appropriate bronze that will be fine for 4000 miles, or is it one with a low yield strength that will fail somewhere in the Badlands of North Dakota? What to do, what to do?

Unfortunately, given that the engine builder used a worn piston in a barrel that he didn't bother to hone and whose axis is slightly askew, I can't trust anything else he did with the engine. There's no point going to all this trouble and then gamble on such a critical component as the connecting rod bushing.

Researching the issue, I found five high performance engine component manufacturers who mention Ampco 18 as the bronze alloy they use for small end bushings. As one example, Ford Racing Parts uses it in the rods for their 521 cu.in. stroker kit (1065 cm3 / cylinder). The yield strength is 37,000 psi vs. the 18,000 of common SAE 660 bronze (used, e.g., in gearboxes).

Although I know Ampco 18 is Cu plus 10.5% Al & 3.5% Fe so I could hunt for a source of generic bronze of the same composition that probably would be less than the name-brand, with materials you have to trust that you will get what the specs say you are getting. Or, I could buy name brand.

So, hi ho, it's off to McMaster Carr I go. I need a final OD of ~1.19" on the bushing to press into the rod but, unfortunately, the tolerance range they specify on the nominal 1-1/4" raw material could result in a rod as small as ~1.18" OD being delivered. So, rather than gamble on this, I stepped up to the larger, and more expensive, 1-1/2". Hey, it's only money, right...

On its way to me is a 12" rod of 1-1/2" OD Ampco 18 for $131, which will leave me with enough extra to rebush my other eight Ariels for a shared cost of only ~$15 ea.... oh, wait, I don't have eight other Ariels. But, at least as far as buying the name brand goes, since McMaster-Carr sells comparable rods of generic SAE 660 bushing material for $111, the premium I paid for knowing I would be getting the right stuff was only ~$20. Well worth it, as far as I'm concerned.

The Catalina is nearly sorted (knock wood), so shortly I should be getting back to the Ariel.
Posted By: kommando

Re: 1928 Ariel Model C - 09/08/17 5:56 pm

I used to purchase the bronze alloys for the Racing Engine Bearing division (relatively low volumes but high value), just going by the chemical composition is not enough, the heat treatment and ancillary processes including extrusion etc changed the final physical properties as well and these were the secret bits that kept the materials such as Ampco 18 being sourced from the only supplier. What was really odd was the high volume production side bearing materials were developed in house so we could have developed alternatives ourselves with little extra effort but as the customers had suggested the material sources it was never pursued, we just showed them the ridiculous invoice values (you don't get much discount for large volumes from a monopoly).
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/09/17 4:37 pm

Originally Posted by kommando
just going by the chemical composition is not enough, the heat treatment and ancillary processes including extrusion etc changed the final physical properties as well and these were the secret bits that kept the materials such as Ampco 18 being sourced from the only supplier.
That's a very important point. When I wrote "with materials you have to trust that you will get what the specs say you are getting" I had in mind the physical specifications more so than the chemical (although it certainly applies to the composition as well).

As a relevant example, Ampco 18 is offered in four versions having the same composition but different heat treatments, resulting in significantly different properties (e.g. the heat treatment for version 18.136 increases its impact resistance by 40%).

A major headache I will face is Al bronze is not the friendliest material to machine so obtaining the tolerance needed in the final press-fit bushing is going to take some effort.
Posted By: kommando

Re: 1928 Ariel Model C - 09/09/17 5:08 pm

I have had the same issue with Aluminium bronze guides, the trick if you end up with a slip fit instead of a press fit in the housing is to copper plate the OD in a copper sulphate solution, varnish the surface you do not need plating. Reaming the ID is best done with a flex/ball hone as HSS reamer wears out before the first cut is finished and just rubs creating heat.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/10/17 4:41 pm

Originally Posted by kommando
Reaming the ID is best done with a flex/ball hone as HSS reamer wears out before the first cut is finished and just rubs creating heat.
If I don't attack the bottom end of the engine in the right order (determine current balance factor, disassemble crank, remove and weigh small end reducing bushing to allow for a revised determination, etc.) it will mean extra work for me. Given that, my current plan(*) for the new small end bushing is to take into account Ampco's machining recommendations to turn the OD to the required oversize for a proper press fit, bore the ID to a to-be-determined size that is smaller than the final size (keeping in mind the ID will be reduced somewhat after the press fit), press it into place, and hone it to the final diameter to give the necessary clearance for the wrist pin. All the while insuring the bore of the bushing is precisely parallel to the crankshaft. Piece of cake, eh?...

Final honing to size may prove to be the most difficult part of this (although, not yet having machined the material, I may find problems there as well). For that my plan(*) is to use an appropriate Sunnen hone that I'll adapt to fit on my mill. Yes, I know I could hand it over to a machine shop to have this done for me but what's the fun in letting someone else screw it up when I can spend more money and time screwing it up myself?

(*)“No battle plan survives contact with the enemy.” Field Marshall Helmuth von Moltke

Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/12/17 9:37 pm

The bar of Ampco 18 aluminum bronze was delivered today but it will be a few days before I see how it machines. Not unlike that on Britbike, advice on machining forums ranges from excellent to... well, let's say, less than excellent. And, like Britbike, it's not possible to know whose advice to pay the most attention to without having spent time following other posts. This is relevant because advice on machining aluminum bronze ranges from saying it cuts 'almost like butter' to 'similar to tool steel', with a range of advice on the cutting edges to use. I think I've sorted all that out but I'll only know once I have it in the lathe.

McMaster-Carr, a favorite supplier of mine, gave a tolerance range on the diameter, and the rod I received came in slightly over the nominal 1-1/2" at 1.55" (also 1/8" longer than the 12" I paid for). However, there's a casting skin on it so I won't know its useful OD until I machine that off. In any case the OD is more than enough than needed to produce the final ~1.19" OD for the bush.

My initial plan is to modify the cutting edges of a sacrificial 25/32" (0.781") Silver & Demming drill to the geometry best for Al bronze that I found from a credible source. That will leave ~0.031 to remove using a boring bar with carbide insert to achieve the 13/16" of the gudgeon pin. I'll leave an appropriate amount of material (~0.001"; exact value to be determined) and sneak up on the final required ID, including the necessary clearance, with a Sunnen hone. Since its thermal expansion is similar to Al I'll allow it to cool before doing the final work on the OD and the ID. Anyway, as Gen. Custer said to Maj. Reno as he rode out that morning, "That's the plan..."
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/15/17 6:10 pm

The honing unit arrived two days ago but I will need to design and make an appropriate holder for it. This unit only operates over the limited range 0.806"-0.837" (nb. 13/16" = 0.812") and is made to be used with a Sunnen honing machine having the necessary mechanism for the push/pull mechanism that operates on the stone to press it against the ID with adjustable pressure.

The stone is mounted on a holder with a 20o ramp so if pushed on by a 1/4-28 cap screw, a one-sixth turn would raise the stone by 0.002". I'll need to fabricate a holder with a bolt operating on it and a strong return spring that is suitable to mount in my lathe. With the small end of the rod in place, turning the cap screw until resistance is felt, plus a little, should be what it takes. I'll practice on a scrap piece of bronze first to get a feel for how fast material is removed.
Posted By: Shane in Oz

Re: 1928 Ariel Model C - 09/16/17 2:14 am

Originally Posted by Magnetoman
The stone is mounted on a holder with a 20o ramp so if pushed on by a 1/4-28 cap screw, a one-sixth turn would raise the stone by 0.002". I'll need to fabricate a holder with a bolt operating on it and a strong return spring that is suitable to mount in my lathe. With the small end of the rod in place, turning the cap screw until resistance is felt, plus a little, should be what it takes.

An M5.5 x 0.5 cap screw should allow finer adjustment, if you can get hold of the appropriate screw and a tap to thread the holder.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/16/17 3:11 pm

Originally Posted by Shane in Oz
An M5.5 x 0.5 cap screw should allow finer adjustment,
Thanks for pointing that out, but I hope finer adjustment won't be necessary. The mechanism I have in mind to make will push against the stone with a spring so it will be encouraged to advance into the bushing rather than being forced to. Unless the stone removes material very rapidly, even with the same setting of the adjustment it should take several sessions of cutting and measuring to approach the desired final ID value.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/21/17 7:52 pm

Although most of the garage time the past three weeks has been spent getting my Catalina Gold Star ready for a friend(*) to ride along with me on my BB Gold Star, that seems to have been accomplished (knock wood). Assuming no significant issues are revealed in the next few days as I put ~200 miles on it prior to a break-in oil change, and after carefully checking over the BB, attention will return to the Ariel.

(*) the Irish friend who sold the Ariel to me

Despite not working on the Ariel it hasn't been off my mind. It's been some years since I last fitted new rings to a bike, and previously I just filed them to get the correct end gap, but yesterday a more serious ring filing jig arrived to use when that time comes. I also purchased a ring expander because I couldn't find mine. Of course, I found the old one after the new one arrived. At least they're of a different design so I'll have a choice.

Although I haven't done any work on Ariel, I did direct some of my attention to the less urgent matter of the speedometer. These were optional accessories at the time and my bike came without one. Before work came to a halt I had bought and installed a speedometer ring gear and 90-degree drive for the rear wheel, and the current drive and driven gears are correct for a ~1600 turns/mile speedometer giving me several easy choices of Chronometric or magnetic speedometers that I already have. However, it would be easy enough for me to machine a new driven gear to give a different ratio so I'm torn whether or not to look for a period-correct speedometer. It's not like this is a critical decision since actual navigation will be handled by a bicycle speedometer that I can accurately calibrate to the actual rolling diameter of the wheel, but I am keeping my eyes open to see what's available.

Anyway, that's where things are at the moment.


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Posted By: old mule

Re: 1928 Ariel Model C - 09/21/17 10:59 pm

Bonnikson, if they didn't cost more than the bike!

Please keep writing, this is the most interest motorbike story on the net right now.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/22/17 4:02 pm

Originally Posted by old mule
Please keep writing, this is the most interest motorbike story on the net right now.
Thanks very much for your comment. I know people read this thread because of the number of views it gets, but it's always nice to have feedback. I'd be happy to stand corrected, but this may be the most complete description of the rebuild of the oldest bike on BritBike.

Originally Posted by old mule
Bonnikson, if they didn't cost more than the bike!
A friend has a Bonniksen on his Levis and it really is the Rolex of speedometers. It was one of two optional speedometers offered for my Ariel in 1928. If the £63 the bike cost then is equivalent to a $15,000 motorcycle today, the Bonniksen at £5.00 would be a $1200 accessory.

Today's Ariel progress was the arrival of a fire extinguisher. At least two bikes have burned to the ground on previous Cannonballs, and a bike that caught fire at this year's Irish Rally was saved by the quick action of a hotel employee with an extinguisher.

A 1 kg Class ABC foam extinguisher (B is for gasoline) has a discharge time of 8-10 sec., which seems to me at least twice as long as is needed. If gasoline leaking from the tank or carburetor is still burning after 8 sec. it's probably hopeless. Anyway, whether right or wrong, after looking at such an extinguisher I decided it was too big and instead purchased a non-refillable 1 lb. extinguisher to carry on the Ariel. I'll have to figure out a way to mount it as far back on the motorcycle as possible in a way that keeps it from falling off but still allows it to be rapidly retrieved.
Posted By: Stuart

Re: 1928 Ariel Model C - 09/23/17 3:32 pm

Hi,

Originally Posted by Magnetoman
A 1 kg Class ABC foam extinguisher (B is for gasoline) has a discharge time of 8-10 sec., which seems to me at least twice as long as is needed. If gasoline leaking from the tank or carburetor is still burning after 8 sec. it's probably hopeless.

Mmmm ... another way of looking at it is, if the initial fire is extinguished in less than 8 seconds, there is some in reserve if the fire reignites? Depending on the size of the leak and the quantity behind it, a leak could go on for several minutes. Extinguishing the initial fire and tipping the bike over could direct the leak away from the initial heat source. But in vain if the vapour reignites from another source and nothing in reserve in the extinguisher?

On that basis, pound-for-pound, might a CO2 or dry-powder extinguisher be more useful? Albeit CO2 isn't the greatest for cooling a heat source quickly.

Hth.

Regards,
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/23/17 4:55 pm

Originally Posted by Stuart
another way of looking at it is, if the initial fire is extinguished in less than 8 seconds, there is some in reserve if the fire reignites? ... might a CO2 or dry-powder extinguisher be more useful?
I can't argue that there certainly could be circumstances where a small extinguisher wouldn't be enough while a bigger one would save the day. In the end the choice requires a (problematic) judgment call on a (problematic) risk assessment.

The fire I observed myself a month ago was caused by fuel dripping from the carburetor being ignited either by a backfire or by a spark from the magneto below it. Either way, once the fire was out there were no more sparks or backfires to reignite it. Although it was hit with two blasts of an extinguisher of less than a second each, I'm pretty sure the fire was out after just the first blast.

A bike burned to the ground on last year's Cannonball when its exposed pushrod came free and punched a hole in the bottom of the tank while underway. I suspect in that case the leak was of such magnitude that by the time the rider managed to stop the bike only a large extinguisher deployed very quickly might have saved it.

As for the type of extinguisher, CO2 works by displacing the oxygen and is great for electronics because it doesn't leave a residue. However, It could require a lot of CO2 in an outdoor location, especially if there were even a tiny breeze. A Type B foam unit is what is recommended for gasoline fires and I can't think of any reason to question this recommendation for an extinguisher to carry on the Ariel. Fingers crossed that I won't have the "opportunity" to find out if my judgment on this is correct or not.
Posted By: RPM

Re: 1928 Ariel Model C - 09/28/17 3:03 pm

I have been looking at these fire extinguishers.

https://www.z1motorsports.com/safet...ean-agent-fire-extinguishers-p-9418.html

I have been looking at the smaller one.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 09/29/17 5:26 am

Originally Posted by RPM
I have been looking at these fire extinguishers. ...
Although halon fire extinguishers are rated for gasoline as well as electrical fires you have to pay quite a bit more for one and it seems to me the advantage they have isn't really relevant for our use. Further, there's the issue of how well they might work in a breeze.

Halon extinguishers leave no residue so they are great for electronics as well as anywhere indoors (or inside a car) because powder or foam would leave a mess on furniture or in carpets. But, not adding additional residue to the outside of a motorcycle engine that's already covered with oil, grease, and road dirt doesn't seem to me to rate a big plus in the 'advantages' column.

A bigger issue is we need them to work outdoors in a breeze, not in inside an office or car. If you cover 90% of a burning pool of gasoline with foam, then pause, you can then resume and put out the remaining 10%. However, if you pause with a halon extinguisher in a breeze, or if it is windy enough and even if you don't pause, as soon as the halon is blown away any remaining flames will quickly have the gasoline back to burning at 100%.

Anyway, for what it's worth, I'm going with a foam extinguisher for the Ariel.

Returning to the Ariel, so to speak, as far as I can tell I now have my Catalina completely finished (knock wood) so as long as nothing develops during a short ride on it and the BB Gold Star this weekend I'll refocus on the Ariel. In another week it will be five months since the Ariel arrived, and there is now less than 12 months remaining before the Cannonball. So much still left to do; so (relatively) little time.

Posted By: RPM

Re: 1928 Ariel Model C - 09/30/17 3:40 pm

The no foam residue is the reason I like this fire extinguisher. If I have a small fire and are able to put it out without the foam residue mess it may be possible to make repairs and keep going. I have cleaned bikes that have had foam all over them. I would pay extra not to have to clean that mess up.
The breeze stuff I did not think about. Going have to check on that.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/01/17 4:58 pm

Originally Posted by RPM
The no foam residue is the reason I like this fire extinguisher. ... without the foam residue mess it may be possible to make repairs and keep going.
I think you're putting too much emphasis on the mess factor. An extinguisher small enough to carry on a bike is only going to put foam in a relatively localized area of the engine and be easily wiped away sufficiently afterwards to fix whatever needs fixing. Foam only would be all over a bike if the fire got big enough that it only could be contained with a large extinguisher, in which case the bike would be toast anyway because it wouldn't be carrying an extinguisher that large.

Originally Posted by RPM
The breeze stuff I did not think about. Going have to check on that.
A large halogen extinguisher could make sense in the evening work area where covering exposed tools and spares with even small amounts of foam from the overspray would be more of an issue. Also, even on a windy day the surrounding buildings and trucks would reduce the breeze in the work area to less than would be experienced by a burning bike on the side of the road in the Badlands of North Dakota.

This issue may be like an oil thread, i.e. there are countless opinions but no "best" answer. Although, similar to oil (i.e. any oil is way better than no oil), in the case of a fire on a bike, any (Class B) fire extinguisher is way better than no extinguisher.
Posted By: old mule

Re: 1928 Ariel Model C - 10/13/17 3:59 pm

I feel like I did when my fave Mexican childrens' show, "Carmella La Bruja" ended.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/13/17 4:29 pm

Originally Posted by old mule
I feel like I did when my fave Mexican childrens' show, "Carmella La Bruja" ended.

Patience. The new season of ‘Ariel’ starts next week.
Posted By: JubeePrince

Re: 1928 Ariel Model C - 10/14/17 1:42 am

Are you releasing the entire season so we can all binge-read?
Posted By: old mule

Re: 1928 Ariel Model C - 10/14/17 3:52 pm

"The future is Unwritten": Joe Strummer
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/17/17 1:14 am

Returning at last to the Ariel, I bought a cheap 4-shelf shelving unit and moved all the Ariel parts, except the exhaust system, from being neatly laid out on the floor to being neatly stacked on the shelves. A few small items had collected on one of the work benches as well, and now they too are on the shelves. As well as helping with the overall organization of the rebuild this freed up a useful amount of floor space that I can now clutter with something else.

An Irish friend, Chaterlea25, offered to look into finding PB1 bronze for me to use for the small end rather than the harder Al bronze I had planned to use. Since he knows from his own experience that PB1 works in this application and is easier to machine than Al bronze it's worth using but, although I can find the composition of PB1 on line, finding an exact match to the equivalent "American" bronze proved problematic. If he can find someone who sells 1-1/4" bars in small quantities the postal service will get rich from transporting it to me.

Making this an all-Irish post, the friend who sold me the Ariel, and who will be my teammate on the Cannonball, arrived for a visit. The pause in the Ariel's progress this past month was due to getting two Gold Stars completely -- I hoped -- ready for the two of us to ride on a 1200-mile mini-Cannonball. Results of that are described elsewhere. It only should have taken a week to get them completely seaworthy but it required nearly a month, consistent with the fact that such estimates always are off by a factor of π.
Posted By: kommando

Re: 1928 Ariel Model C - 10/17/17 7:41 am

Mallard Metals sell PB1 1 1/4" by the inch at £6.20.

www.mallardmetals.co.uk
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/17/17 6:38 pm

Originally Posted by kommando
Mallard Metals sell PB1 1 1/4" by the inch at £6.20.
Thanks very much for this information.
Posted By: kommando

Re: 1928 Ariel Model C - 10/17/17 7:29 pm

You won't pay the Vat at 20%, EU residents do, I checked the website and they internationally.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/17/17 8:59 pm

If yesterday's hurricane hasn't submerged him I think my Irish friend already has located a piece of the PB1 bronze from a local source.
Posted By: old mule

Re: 1928 Ariel Model C - 10/17/17 10:35 pm

Don't forget that certain lubes are not compatible with phosphor-bronze, many Triumph owners have found their gearbox bushings deteriorated by the wrong lubricant.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/17/17 11:15 pm

Originally Posted by old mule
Don't forget that certain lubes are not compatible with phosphor-bronze,
The issue is when sulfur is used as an additive to give grease or oil the Extreme Pressure (EP) rating needed for use in gearboxes. However, the bronze in question will be for the small end and therefore only exposed to oil. Although I will use Morris 400EP semi-fluid grease, along with a dash of Millers Classic Green Mineral Oil, in the gearbox, the Morris passes a Cu corrosion test (and is widely used without problem in Burman gearboxes) and the Millers is a non-EP formulation.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/19/17 8:52 pm

Originally Posted by Magnetoman
The new season of ‘Ariel’ starts next week.
I hope this is still true, i.e. next week. I decided it best to fix the issues that arose on my Catalina during its recent ~1000-mile run while they're still fresh in my mind before turning full attention to the Ariel. With luck the Catalina will be completely ready to go again, um, mañana. I should have everything I need to take care of it already in hand, with the exception of new Hagon shocks now on their way to me from British Cycle Supply.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/20/17 4:19 pm

Despite me working on the Catalina, progress is being made on the Ariel thanks to Chaterlea25. A 4" rod of 1-1/2" OD PB1 bronze arrived yesterday from Ireland so I now have everything in hand to make the reducing bushing for the small end. In case anyone is interested, the yield strengths of three common bearing bronzes are:

SAE 660 __ 14-20 ksi
PB1 ______ 25 ksi
Ampco 18 _ 41 ksi

Despite Ampco 18's greater yield strength it is much harder to machine than the other bronzes and Chaterlea25 assures me he has successfully used PB1 in small ends for years without problem.

I don't know what kind of steel the rod is made from but, even assuming the worst for its coefficient of thermal expansion, a PB1 bushing with a 0.002"-0.003" press fit will be nicely retained even if the rod is glowing red from the amazing h.p. generated.by the Ariel's engine. It will be trickier to hone the bushing to the final ~0.0005" clearance needed for the pin but I have the necessary Sunnen mandrel so "only" need to design and make an adapter for it to mount in my lathe.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/22/17 4:38 pm

My Catalina returned from its ~1000-mile ride along with a list of 14 items that need attention (e.g. solder replacement nipple on valve lifter cable). Although I've only managed to cross 4 items off that list so far, it only should take another day or two to deal with most of the remaining. The time-consuming two items will be to completely rebuild an ASCT gearbox to swap for the current SCT, and to rebuild the forks.

The gearbox is now in a million pieces on my workbench and last night I sent C&D Autos a list of the necessary bushes, gaskets, etc. so I hope to have them in hand within two weeks. Meanwhile, I have at least some of what I need (e.g. NOS Torrington needle bearings) so I can get a good start on the gearbox rebuild while waiting for the parts to arrive.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/24/17 3:14 pm

After a lengthy silence, yesterday we got an update on the Cannonball. The update to the website that has been listed as "Coming Soon" since March is now expected to happen "hopefully within the next few weeks." Meanwhile, since the web site is still being worked on, next week names of the riders will be sent to us via email next week.

There are 105 riders signed up and the final route will be 3875 miles with the list of cities along the way "coming soon," but the schedule will be:

September 6, 2018 Official Registration/Tech Inspection
September 7, 2018 Official Registration/Tech Inspections/Rally School/Practice Run/Banquet
September 8, 2018 Depart Portland, Maine
September 16, 2018 Arrive in Sturgis, SD
September 17, 2018 Rest Day Off, Sturgis, SD
September 23, 2018 Grand Finale Portland, OR

The update says they've secured blocks of all the hotel rooms needed but a web page to secure individual reservations won't be posted until May.

That's all that I know about it for now.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/25/17 5:31 pm

The last day of my recent "mini-Cannonball" Gold Star ride covered 300 miles with stops only for gasoline and a quick lunch. I soldiered along all day on my BB at a steady 3000 rpm (43% of the 7000 rpm redline) and it felt like the engine would last forever. So, with that in mind:

I infer from Ariel's literature that they considered ~5500 rpm as redline for this engine and I'd like to gear it to keep the engine at or below 50% (or 43%), of redline for maximum reliability on this long ride. The Ariel already has the largest listed engine sprocket (23T), but I'm now hoping to find a gearbox sprocket that is larger than the 19T that's on it now.

With present gearing 50% of redline is 48 mph (41 mph at 43%) so, for example, if I were able to substitute a 20T gearbox sprocket that would increase to 50.5 mph (43.3 mph) and with a 21T to 53 mph (45.5 mph).

To someone in England an additional 5 mph may not seem like much, but if you look at a map of the U.S. Midwest (or of Canada, or central Australia) you'll see that there are stretches of road that are essentially straight for 400+ miles. Every mph helps get to the destination sooner, and every decrease in rpm allows the engine to last longer.
Posted By: RPM

Re: 1928 Ariel Model C - 10/26/17 4:35 pm

3875 miles in 15 days of riding means some 300 mile days on the Cannonball. A happy cruising speed of 50mph would be great for sure.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/26/17 9:51 pm

Originally Posted by RPM
A happy cruising speed of 50mph would be great for sure.
I've now learned that Burman used a different spline on later gearboxes so finding a donor sprocket on which to weld a ring with more teeth isn't going to be easy. However, I don't think I'll have trouble being ready for the start of the Cannonball next September thanks to my full time mechanic, machinist, purchasing agent, travel agent, logistics specialist, and project manager to keep everyone on task and on schedule... oh, wait, I don't have any of those people...
Posted By: gREgg-K

Re: 1928 Ariel Model C - 10/26/17 11:16 pm

Originally Posted by Magnetoman
<SNIP> However, I don't think I'll have trouble being ready for the start of the Cannonball next September thanks to my full time mechanic, machinist, purchasing agent, travel agent, logistics specialist, and project manager to keep everyone on task and on schedule... oh, wait, I don't have any of those people...

Oh yes you do, it's just that they're all occupying the same body ,,,

.. Gregg
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/27/17 12:42 am

Originally Posted by gREgg-K
it's just that they're all occupying the same body ,,,
You can't get decent help these days. If my purchasing agent had been halfway competent he would have thought to check Draganfly's web site to see if they have the sprocket, which they do. It's pricey at £65.63, but I already had resigned myself to fabricating the sprocket by broaching the appropriate splines in a blank so I had a fair idea how much time that would take.

So, on order from Draganfly is a stock 19T sprocket that my project manager will have my machinist butcher into a 21T or 22T.
Posted By: kommando

Re: 1928 Ariel Model C - 10/27/17 8:02 am

Just remember to get the team together at least once a month or they will all go off doing their own thing wink
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/27/17 3:15 pm

Originally Posted by kommando
Just remember to get the team together at least once a month or they will all go off doing their own thing
The weakest link is the project manager. However, I'm stuck with him for the duration because his job security on this project makes that of French workers seem almost non-existent.

p.s. On the subject of sprockets, I learned this morning that the entire crankshaft sprocket and cush drive assembly from later Ariels would fit on my 1928 engine, which would give me access to a wider range of sizes. Also, less drastic surgery is needed to swap engine sprockets which would be a big advantage if this turns out to be necessary midway in order to make it over the Rocky Mountains.

The road to the top of an 8000 ft. mountain starts 10 miles from where I live so that will be my initial test track for carburetor and gearing issues. Once I'm happy with how it seems to be working I can trailer the bike 175 miles (100 of which is via 75 mph Interstate highway, hence the need for trailering) to the start of a ~200-mile loop through the mountains, most of which is over 6000 ft. and half over 8000 ft.

Although it's possible the organizers could announce a route that could take us as high as 10,950 ft. my tests at somewhat lower altitude should give me a good idea whether I can keep the same gearing for the entire Cannonball, or if I will be forced to change sprockets to get over the Rockies. If properly rejetted for the thinner air the h.p. loss is ~3%/1000 ft. so it will be ~10% less at 11,000 ft. than at 8000 (fully 1/3 less than at sea level). How much my Ariel struggles at 8000 ft. will give me a good idea how it will deal with 11,000 ft. Having mountains at my disposal gives me a bit of an advantage in preparation over someone who lives in Kansas. Of course, it's only an advantage if I get the bike prepared in time to do that testing...

I plan to buy X-ring chains which should be good for the 4000 miles without any lubrication, although I would hit them with a daily dose of chain lube to keep external rust away and provide lubrication between the chains and sprockets. Does anyone have any experience with X-ring chains under these conditions of minimal maintenance that indicates this isn't a good plan?
Posted By: Shane in Oz

Re: 1928 Ariel Model C - 10/27/17 8:29 pm

Originally Posted by Magnetoman
I plan to buy X-ring chains which should be good for the 4000 miles without any lubrication, although I would hit them with a daily dose of chain lube to keep external rust away and provide lubrication between the chains and sprockets. Does anyone have any experience with X-ring chains under these conditions of minimal maintenance that indicates this isn't a good plan?

My Triumph Sprint has an X-ring chain, which has only needed adjusting once in ~ 3,000 miles. It gets a hit of Bel-Ray spray chain lube every 250 miles or so on the road or when I get home from a ride.
I don't know how well one will stand up to the Ariel's 25 h.p. and 300 lb. as compared to the Triumph's mere 120 h.p. and 550 lb.
Posted By: Alan_nc

Re: 1928 Ariel Model C - 10/27/17 9:05 pm

Can I jump ahead with a question:

We have all been following the 'build' with interest. It really is fun particularly if you don't have to spend the money or worry about the end result.

My Question: Are we going to be able to follow you during the ride?
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/28/17 3:16 am

Thanks to Kurt Fischer a Chronometric arrived today that is perfect for the Ariel. Although age-inappropriate, its 80 mph range is suitably optimistic for the bike (as opposed to one with a 120 mph range), and it was supplied on 1952 'Road Model' Gold Stars. The reason that's appropriate, for me at least, is that ten years after Val Page designed the 'Black Ariel' range he was at BSA where he designed the B and M range, i.e. the Gold Stars we know and love (the first model was an M24).

I already had installed a speedometer sprocket on the rear wheel, and have the necessary angle drive, so all that is needed is to machine a drive sprocket to give the correct 1600 turns/mile.

Originally Posted by Shane in Oz
I don't know how well one will stand up to the Ariel's 25 h.p. and 300 lb. as compared to the Triumph's mere 120 h.p. and 550 lb.
It's too bad the parameters of your Triumph are so different that it's impossible to infer from it how long an X-ring chain would last on my Ariel. I'll just have to cross my fingers and hope for the best.

Originally Posted by Alan_nc
Are we going to be able to follow you during the ride?
I'm not sure anyone would want to read "Today was an uneventful 250 miles on a dead-straight road in the Midwest; tomorrow will be the same." Almost by definition, if I had something interesting to write about at the end of the day (e.g. "The rear tire shredded at 60 mph nearly killing me and bending the frame which now needs straightening") I would be too busy dealing with it that night to write about it.

In 6 months this thread has gathered 2x as many views in the Ariel forum as the next one that has been here for 8 years so there's interest. So, it might be worthwhile to look for a social media manager within my multiple personality disorder since there's the possibility to reach a substantial number of people with some effort. But, other than Linkedin, which I was "forced" to join two years ago and as a result where I'm now connected to ~2000 of (presumably) my nearest and dearest colleagues, I've avoided social media. Unless you count Britbike as social media, that is, which it certainly seems to be in the Facebook sense for a half-dozen who always seem to be in the Shout Box when I glance at it.


Attached picture IMG_6648.JPG
Posted By: robcurrie

Re: 1928 Ariel Model C - 10/28/17 5:38 am

The Cannonball website usually has a daily summary of events and photos/videos (somtimes of flaming wreckage) as well as the results for the day showing positions. I think the report is usually by the sweep marshal whose job it is to, well, sweep up the mess.
Rob C
PS : Last time social media was very involved after the event when it was used to find a truck full of 'bikes and spares that were stolen from a competitor.
Posted By: Stuart

Re: 1928 Ariel Model C - 10/28/17 2:29 pm

Hi,

Originally Posted by Magnetoman
I plan to buy X-ring chains which should be good for the 4000 miles without any lubrication, although I would hit them with a daily dose of chain lube to keep external rust away and provide lubrication between the chains and sprockets. Does anyone have any experience with X-ring chains under these conditions of minimal maintenance that indicates this isn't a good plan?

Oldest 'O'-ring chain I have is 25 or 26 years old. I fitted it to a '77 CB750A shortly after I bought the bike in '91 or '92, that I was using for a daily 70-mile round-trip all-weather commute. I also fitted a Scottoiler (although, at the time, it wasn't called a "vSystem" 'cos it was the only one Fraser Scott sold). Chain adjustment reduced from a regular weekend chore to one or two flats on the adjuster bolts at the 1500-mile service intervals. I did about 10,000 miles - taking the chain adjustment about half-way - before changing jobs and not needing to ride the bike every day.

Although I appreciate it isn't a consideration on the Cannonball, one of the reasons the chain's lasted so long is, because it and the rollers on the sprockets are lubed and cleaned all the time the bike's being ridden, all the bits are lubed and clean at the end of a ride without me needing to do anything. When I first fitted the chain, sprockets and Scottoiler, this was useful as I could arrive home after a wet ride from work, put the bike in the garage, leave it for a period and return to a working chain rather than a solid rusty bar. Now that's just handy if I don't ride the bike for a period of time.

Subsequently, Fraser Scott advised that, if lubed with a Scottoiler, chains on my other bikes didn't need to be '-ring' ones; that was also handy because Triumphs aren't noted for their generous clearance around the gearbox sprocket ... so far, I've yet to need to replace a Scottoiler-lubed chain.

I appreciate a 1928 Ariel probably doesn't have a vacuum take off to run one of those chain oilers, but there are electric ones, and cheaper ones of the different types by other makers.

Originally Posted by Magnetoman
Linkedin, which I was "forced" to join two years ago and as a result where I'm now connected to ~2000 of (presumably) my nearest and dearest colleagues

Tch, you aren't trying ... Can't remember how long I've been on LinkedIn (much longer than two years) but I still get regular emails saying how "13 more contacts [to 30] will accelerate [my] career" ...

Probably rules me out as your social media manager? cool

Hth.

Regards,
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/28/17 4:48 pm

Originally Posted by Stuart
I appreciate a 1928 Ariel probably doesn't have a vacuum take off to run one of those chain oilers, but there are electric ones, and cheaper ones of the different types by other makers.
Someone in the Ariel club also suggested adapting a Scottoiler, not for the chain, but for the exposed valve gear. I looked into it and there is a place above the engine, between the frame tubes, where one would fit. Unfortunately, instructions for the vacuum operated version say it needs a minimum of 30 cm pressure head in order for the oil to flow, and the electric version requires the same plus, well, electricity, which is in very short supply on the Ariel. So, unless I mounted a gravity-fed oiler on a gantry 6" above the top of the fuel tank it wouldn't work for lubricating the valve gear.

Offline someone asked me about my plans for the gearing. In case anyone else is interested, the overall ratio of the Ariel in top gear at the rear wheel with the current, stock gearing is:

engine/clutch x gearbox/rear = 23T/44T x 19T/47T = 0.2113

That is, one revolution of the engine results in 0.2113 turns of the rear wheel so in one minute at 3000 rpm the wheel makes 633.9 revolutions. Since the rear tire has a circumference of ~85", in one minute it travels ~633.9 revs x 85"/rev x 1 ft./12 in. x 1 mile/5280 ft = ~0.85 miles. One mile/min. is 60 mph so this overall gearing means ~51 mph at 3000 rpm.

The Ariel's overall gearing in top gear of 0.2113:1 is 4.8% higher than that of my BB Gold Star which is 0.2017:1. They have the same rear tire so at 3000 rpm on both machines the Ariel would be traveling 4.8% faster.

The reason to increase the overall ratio of the Ariel in top gear wouldn't be to go faster, but to lower the engine rpm at a given road speed. Specifically, to bring the engine speed down to ~2500 rpm at 50 mph. However, increasing the overall ratio also increases the ratio in the lower gears.

Comparing gearboxes, 1st gear in the Ariel is 2.79:1 vs. 2.58:1 of the BB, i.e. the Ariel is 8% lower. Hence, if I swap a 22T gearbox gear for the current 19T in order to increase the overall ratio by 15.8% it will make 1st 7% higher than that of my BB. That is not insignificant, but based on how the BB performs (albeit, having more h.p.) I have reason to expect that it will be OK for the intended use on the Cannonball. However, I'll only know for sure when I finish the bike and am able to test it.

By the way, the difference between low and high in the 3-speed Ariel gearbox is 2.79, which is close to the 2.58 of the BB's STD gearbox and the 2.88 of an SCT.

I'm making a big push to finish my Catalina this weekend. I've already decided to forego rebuilding the forks at this time, so what remains is to finish rebuilding the ASCT gearbox and swap it for the SCT that's in the bike now. Luckily, I found that I had everything needed for the rebuild on hand because I haven't heard back from C&D about the order I sent them six days ago. I sent them a reminder, but still without response.

While on the subject of gearing, the ASCT was a one-year-only gearbox for 1962 Catalinas like mine, with the same ratios for 2nd-4th as the SCT but with a significantly lower 1st. I'll also be swapping the "scrambles" 18T engine sprocket on it now for a "touring" 21T sprocket, raising the overall ratio by 17% to make it significantly less buzzy at highway speeds. Although that also will raise first gear it still will be 5% lower than it is now thanks to the ASCT gearbox.

Originally Posted by Stuart
Can't remember how long I've been on LinkedIn (much longer than two years) but I still get regular emails saying how "13 more contacts [to 30] will accelerate [my] career" ...
For reasons not worth explaining I was forced to join, and since I was in anyway I've tried to think of ways it might be helpful. Unfortunately, maybe it's because of the career I have, but I have not been able to figure out how Linkedin might be useful for me. But, I accept new contacts when I don't think they will require any effort from me to respond (e.g. not from sales people, anyone in temporary positions unrelated to mine, etc.), and quickly delete them if they do, so I'm ready to exploit the hell out of Linkedin if/when I ever figure out what it's good for.
Posted By: triton thrasher

Re: 1928 Ariel Model C - 10/28/17 5:26 pm

The Ariel doesn't have a vacuum take-off, but it does have vacuum. You can make an attachment for a Scottoiler vacuum pipe.

If you can't get enough head (Quiet at the back!) above the valve gear, why not slightly pressurise your reservoir of oil? That used to work just fine on some car windscreen washer sets.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/28/17 6:42 pm

Originally Posted by triton thrasher
why not slightly pressurise your reservoir of oil?
Giving it head violates the KISS principle. Adding a pressure system would complicate matters. If it failed, and was noticed in time, access to the oiler would require removing the fuel/oil tank, on which the hand gearchange mechanism is bolted. Further, if an oiler fails to oil the chain it's not a huge deal, but if fails to lubricate the valves it's a potential disaster.

Posted By: George Kaplan

Re: 1928 Ariel Model C - 10/28/17 6:42 pm

triton thrasher, there are some other oilers available that don’t need the vacuum take off. Some are just drip feed with a tap but others work by only dripping oil when the bike is moving using a sort of mechanical motion sensor so MM wont necessarily need the vacuum take off if he goes for an oiler. I suspect MM knows about all of this already.

Hi MM, I finally joined the forum, you know me as the guy who currently has a broken finger.

GK
Posted By: triton thrasher

Re: 1928 Ariel Model C - 10/28/17 7:07 pm

Originally Posted by Magnetoman
if fails to lubricate the valves it's a potential disaster.



You're more worried about it than the makers were.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/28/17 8:06 pm

Originally Posted by triton thrasher
You're more worried about it than the makers were.
True, but then I again perhaps I know more about the lubrication issue than the makers knew 90 years ago. Even they knew more a few years later than they did when they made my bike, when they realized they needed to enclose the valves and provide them with proper lubrication.

Ixion writes in Chapter 14 'The Fifth Phase--1920 to 1930' of 'Motor Cycle Cavalcade' that "Certain items of air-cooled engines -- notably, the cylinder bore, the valve faces, and the piston rings -- wore far too fast, confronting the owner with the choice between costly renewals and rattles plus inefficiency." ... "One more problem of a less obvious character clamoured for solution. Hitherto, practically all four-stroke motor cycles had been lubricated on the 'total-loss' method... Whatever oil was present in the crankcase was always extremely hot... Every 3,000 miles or so we removed carbon deposits from the engine." At the end of the chapter he summarizes the result of the decade's technical developments on reliability by writing "If I take the Flying Scot to Edinburgh, I do not report...that it covered its 400 miles without a breakdown." It's great that the ability to cover 400 miles without a breakdown was no longer newsworthy by 1930, but the Cannonball is 4 thousand miles.

I'm pretty sure that when Val Page designed the 1928 Ariel's engine he didn't do so with the idea it survive riding Lands End to John O'Groats 4.5 times in two weeks with minimum maintenance.
Posted By: Stuart

Re: 1928 Ariel Model C - 10/29/17 11:25 am

Hi,

Originally Posted by Magnetoman
Scottoiler,
for the exposed valve gear. I looked into it and there is a place above the engine, between the frame tubes, where one would fit. Unfortunately, instructions for the vacuum operated version say it needs a minimum of 30 cm pressure head in order for the oil to flow,

Hmmm ... I never knew that ... the one on the Honda is on the frame tube behind the sidepanel - 6"? above the bottom of the rear sprocket, the ones on Triumphs are behind the numberplates under the '73-on rear lamps. Worth an e-mail to Fraser Scott?

Certainly for a chain, I've found the position of the end of the delivery tube is far more important than the quantity of oil delivered. With the delivery tube end by where the bottom run of the chain runs on to the rear wheel sprocket, I ended up with the Scottoiler set to one position above minimum in the dry, increased by one position in the wet; any more and the back of the bike is just covered in more oil. The O-ring seals on the split-link were easy to check; long term, the remainder of the chain is obviously fine too. smile

Originally Posted by George Kaplan
oilers available that don’t need the vacuum take off. Some are just drip feed with a tap but others work by only dripping oil when the bike is moving using a sort of mechanical motion sensor

I looked at these when I was getting ready to fit that first O-ring chain, plus at least one that worked with the up-down motion of the swinging arm. However, I got that first Scottoiler at mate's rates and have been happy with 'em ever since, so couldn't say what other varieties are still available today.

Originally Posted by Magnetoman
I have not been able to figure out how Linkedin might be useful for me.
I'm ready to exploit the hell out of Linkedin if/when I ever figure out what it's good for.

You 'n' me both. I'll share if I figure it out first.

Regards,
Posted By: triton thrasher

Re: 1928 Ariel Model C - 10/29/17 1:12 pm

You are allowed to try it with less than 30 cm.

Posted By: George Kaplan

Re: 1928 Ariel Model C - 10/29/17 2:24 pm

I suspect that MM wants to keep it simple (K.I.S.S.). Therefore the simplest oiler (assuming MM want to fit an oiler) is the "Loobman"

Plenty on google about it. Basically a bottle that you squeeze before a ride. Squezing it puts some oil in a tube which then drips out of the tube as you ride. You can control the amount of oil per dose by varying the length of the tube.

Not as sophisticated as a vacuum or electronic system but certainly conforms to the K.I.S.S. principle.

GK
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/29/17 3:26 pm

Originally Posted by George Kaplan
I suspect that MM wants to keep it simple (K.I.S.S.).
Exactly. The advantage of an automatic valve train oiler is it would be set and forget. The disadvantage is, having forgotten about it, if (when...) it failed it likely would be too late once discovered.

The Ariel manual calls for lubricating (with grease, not oil) the tappet/valve top and the cups at both ends of the pushrods every 200 miles, as well as the rocker shafts every 300-400. OK, oil delivered regularly and in sufficient quantity could be as good as grease applied periodically, but an automatic oiling system couldn't do anything for the shafts since they have Zerks and require pressure to inject the lube. Also, it would require complicated routing for the other 6 outlets. Further, if oil were used instead of grease it would take a fairly good flow of it to do the same job. Whatever the quantity, all of that oil would be "total loss" so would end up coating the bike and rider.

Then there's the issue of ensuring equal flow from all 6 outlets. I have a "semi-automatic" lubing system for my mill at work where one pull of a lever injects oil through ~6 outlets onto the ways. The problem with it is without close inspection every time it is impossible to know if any of the outlets is clogged. So, I did not install such an oiling system on my mill at home, instead lubing the Zerks individually. It's more of a headache to do it that way, but if any Zerk is clogged I'll immediately know it.

The fuel tank gives me a range of ~100 miles. Since I'll be stopped anyway it only will take another ~2 min. to grease everything with a pistol-type grease gun I've already modified for the purpose. But, I'll keep an open mind about this. Perhaps an oiler pressurized by motion of the Ariel's swinging arm...



Posted By: George Kaplan

Re: 1928 Ariel Model C - 10/29/17 3:46 pm

Originally Posted by Magnetoman
Perhaps an oiler pressurized by motion of the Ariel's swinging arm...


I am not sure that there is a system available that is compatible with the type of swinging arm that was fitted as standard to 1920's Black Ariels. smile

GK
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/29/17 4:17 pm

Originally Posted by George Kaplan
I am not sure that there is a system available that is compatible with the type of swinging arm that was fitted as standard to 1920's Black Ariels.
That's great news, and my Google searches thus far seem to confirm it. This means I can design one and go into business selling them knowing I've cornered the market for swinging arm-powered oilers for 1926-30 Black Ariels.

I can start spending the estimated profits now since the money soon will be rolling in. However, it would be selfish of me not to share my good fortune, so shares in my company are available now at a special introductory rate of only $100 ea., with the size of the IPO strictly limited to the number of people who buy them.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 10/29/17 4:53 pm

smile MM, dont plan your retirement just yet!

On a serious note, I think you are right in sticking with just getting into the habit of doing the valves at every stop. MY comments about a chain oiler were only in reference to oiling the chain.

There were lots of bikes with open valve gear on previous Cannonballs and I am pretty sure that most of them were OK.

GK.

Posted By: kevin roberts

Re: 1928 Ariel Model C - 10/29/17 5:43 pm

Originally Posted by Magnetoman

The fuel tank gives me a range of ~100 miles. Since I'll be stopped anyway it only will take another ~2 min. to grease everything with a pistol-type grease gun I've already modified for the purpose. But, I'll keep an open mind about this. Perhaps an oiler pressurized by motion of the Ariel's swinging arm...


but how would maintain a minimal oil flow at stops, with the engine running, while you attended to other tasks?

wait, i've got the answer-- an automatic swingarm activation device. dunno how you fit it, though. no need to pay me for this suggestion.



Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/29/17 8:08 pm

Originally Posted by kevin roberts
wait, i've got the answer-- an automatic swingarm activation device.
I've had experience with this type of device before and found them to be quite maintenance intensive, especially when new, although with an ever-increasing cost of maintenance as they aged. However, like many things, perhaps newly manufactured ones have been improved(?). Since most are produced in China and India, and importation of such devices became increasingly uncertain this year (and soon will be in the UK as well), are you aware of a domestic supplier? If so, can they be returned for a full refund if they develop leaks?
Posted By: kevin roberts

Re: 1928 Ariel Model C - 10/30/17 2:01 am

i'm afraid leaks are unavoidable
Posted By: Richard Kal

Re: 1928 Ariel Model C - 10/30/17 10:29 am

Clever Val Page used the total loss oil system for the 27 - 28 black Ariels to lubricate both chains. there is (should be) a short tube from the LH side crankcase breather hole, to direct the oil mist onto the primary chain.

There is a longer one connected to the breather hole (3/8 bsw) at 11 o-clock on the RH crankcase half. The longer pipe connected to this fitting will direct oil onto the secondary (wheel drive) chain.

K.I.S.S.!!!

Richard
Posted By: Magnetoman

Re: 1928 Ariel Model C - 10/30/17 4:24 pm

Originally Posted by Richard Kal
Clever Val Page used the total loss oil system for the 27 - 28 black Ariels to lubricate both chains.
I'm sure the lubrication quality of overcooked engine oil is better than nothing so it, plus X-ring chains, plus daily doses of actual chain lube should keep the chains going for the required 4000 miles. It's too bad clever Val didn't hit his stride with valve train lubrication until a few years later.

p.s. All the actual experience with Black Ariels seems to come from Australia (plus England, of course). Only a trickle must have been exported to Canada and the U.S. But, this applies to all brands of pre-WWII British bikes.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/10/17 4:11 pm

While getting two Gold Stars ready for last month's 1200-mile ride and then addressing issues with them that came up on the ride (e.g. fabricating a new taillight/license bracket for the Catalina) kept me from doing any actual work on the Ariel for several months, that's about to change. However, not working on it doesn't mean I haven't been thinking about it. A major Ariel-related issue that requires thought, not work, is deciding how best to get it to and from the Cannonball.

What tools, spares and supplies I decide I need to bring affects transportation. The fact Google says the starting line is 40 hours by road from home also affects transportation since I don't want to spend 4-5 long days driving just before getting on the bike. If I succeed in rebuilding the Ariel to as-new standards the bike should be good for the 4000 miles without any maintenance, and hence I wouldn't need to ship anything other than the bike. Toward the other extreme, enough tools and spares to completely rebuild the bike in a motel parking lot if necessary might be prudent.

Without going into detail or describing variations, the choices seem to be:

-- Ship the bike in the crate used to get it here from Europe, filling empty spaces with whatever clothes and minimal tools and spares that fit. Airlines allow two checked bags up to 50 lbs. ea. for carrying additional items. Rent a box van in Maine for the team driver, to carry the crate and tools and, I hope not, our bikes if either breaks down beyond being able to be repaired overnight..

-- Build a larger crate. The one my teammate uses is 15.3" longer, 8.8" wider and 4.2" taller than mine, allowing that much additional volume for extras. The cost to build a larger shipping crate would be a few hundred dollars and presumably it would cost more to ship as well, although I'd confirm that ahead of time.

-- Buy a 10'x6' enclosed trailer and pack it with lots of tools and spares along with the bike and rent a pickup truck in ME for the team driver. Such trailers appear on Craigslist with asking prices of ~$1-1.5k and quotes for shipping one filled with 800 lbs. of goods to Portland ME were $1.5-2k (presumably less to ship back from Portland OR, but I didn't ask). Most of the trailer cost could be recovered by selling it afterwards but the total shipping at both ends of the Cannonball would be at least $2.5k more than that of a bike crate.

Even with a trailer I couldn't take a lathe, TIG welder, hydraulic press etc. so it's not like that option would let me be prepared for anything that possibly could happen. Clearly, how much to bring requires both risk assessment and cost/benefit analysis. While some things at the extremes are fairly obvious (e.g. the risk that a lathe might be needed is fairly small while the cost to bring one would be large, whereas the opposite is true for packing an extra tire) it would be very helpful to hear from those of you with actual experience.

At the moment I'm leaning toward the larger crate option. Comments?
Posted By: George Kaplan

Re: 1928 Ariel Model C - 11/11/17 9:19 am

Hello MM, your question is something that we all ponder whenever we plan a trip and there is no right or wrong answer (which you know already) and everyone will have a different opinion. Also, I don’t have any first hand experience of the Cannonball so you really need the input of previous participants. Preferably one of the ones who didn’t have unlimited budgets and a support crew rivalling the number of extras in a Cecil B Demille movie.

However here are my thoughts.

I think that your decision on what to take with you (which will drive the answers to the other questions) will depend on how much confidence you have on the bike and its various components to last the distance. The level of confidence will, I believe, depend on when you get the bike back together and how much time you have to put miles on it and get to know it before you have to make the final decision on crate size or trailer or van etc.

Also, even with a high level of confidence in the bike, there is always the risk of an old component failing without warning (I am assuming that you are not replacing 100% of the bikes old parts). Some of these parts are probably small and easy to carry, girder fork spindles for example. Some not so small such as the crankshaft or cylinder.

The next question is how to ship it? For me, my most valuable resource is time so I would ship the bike to the start so that rules out driving but I think you have ruled that out already yourself.

The next bit is easy, van hire vs Pick-up hire (using your own trailer). For me this is a simple maths question. Work out the costs of the two options and go for the cheapest.

Also you may want to consider security when you stuff is unattended, remember the trailer that was stolen in a previous Cannonball. You can get a tracker for quite a small cost which would give you peace of mind which ever way you go?

I would not worry about large tools. Looking at previous years reports it seems that there were lots of people along the way with fully equipped machine shops who have helped out at the drop of a hat so I am pretty sure that if you did need, say a lathe, you could find one to use pretty quickly.

The last bit therefore depends on the above maths question. If the trailer is cheaper (which I suspect it isn’t) then you have your answer regarding shipping method.

If not then its a matter of how much stuff to take which drives the crate size. Personally I would probably go for the larger crate at this stage although I would get shipping quotes now just to make sure its not thousands of dollars more to ship the bigger box.

Also, if you cant fit some items in or decide they are not needed, could you pack them up and leave them clearly labelled in you home shop. Then, in the unlikely event that they are needed, your wife/daughter/friend could get the relevant package express shipped to you overnight. You would lose a day but at least you would still be in it.

On the subject of boxes, have you considered a box with a metal frame and then thinner plywood infill sides? I have seen people use them in other posts on AdvRider and Horizons Unlimited and I assume you get a bit more internal space for the same external volume plus I think they might be lighter compared to an all timber box of the same size.


Like I said at the start I don’t have first hand experience so this is all just my ramblings. An actual Cannonballer might come along in a minute and give you some proper advice.

John
Posted By: koncretekid

Re: 1928 Ariel Model C - 11/11/17 12:05 pm

I drive 3000 miles every spring and fall to Colorado from Nova Scotia and then another 600 miles on to Bonneville a couple of days later. In the fall, I tow my 5' x 10' enclosed trailer with my land speed racing bike (9' long) with tools and spares with my Toyota Venza. I always find the week preceding the trip with packing up and trying to allow for all possible spares and tools more stressful than the actual drive. The drive to Colorado takes about 40 hours over 3-4 days and I do 90% of the driving. Satellite Radio and NPR and the GPS are your friends along the way. The big advantage of an enclosed trailer with torsion suspension and the ramp rear door is the ease with which you can load and unload and the peace of mind that it will always be with you. These trailers tow so easily (single axle), and with the narrower 5' wide model, you don't even know it's there until you look at the gas gauge! And I dare say you could fit a Thermal Arc 95-S Tig welder in the trailer as well.

Tom

P.S. A trailer like this:
https://ocala.craigslist.org/fod/d/2017-5x10-enclosed-trailer/6359180178.html
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/11/17 4:39 pm

Originally Posted by George Kaplan
However here are my thoughts.
Your thoughts on this are greatly appreciated. The 40 hour drive isn't just a matter of time and cost (gasoline and hotels add up so it's not "free" to drive), but exhaustion as well. It took two days after the 12-hour drive back from Texas last month for the effects to wear off.

Originally Posted by George Kaplan
I think that your decision on what to take with you (which will drive the answers to the other questions) will depend on how much confidence you have on the bike and its various components to last the distance.
Maybe it's just me, but even with high confidence in a bike, knowing that I have tools to deal with unexpected issues, even when I don't expect unexpected issues, relieves pressure. I have a highly developed 10 lb. toolkit I strap to the mudguard so that when on the road a noise or rattle becomes something to deal with at the next stop, as opposed to a cause of anxiety since I would have no way of solving the problem if it got worse. Even when things might be going beautifully on the Ariel, just knowing that a wide range of tools and spares are waiting at the motel that evening would relieve pressure so would be well worth having even if I never had to use them.

Originally Posted by George Kaplan
You can get a tracker for quite a small cost
I hadn't thought of that. Thanks for mentioning it.

Originally Posted by George Kaplan
have you considered a box with a metal frame and then thinner plywood infill sides
I haven't looked into the options, which includes getting shipping estimates. As you said, it's possible that having a crate that's just 1" over some size might put it into a significantly higher price category. I'll now look into "composite" crates as well.

Originally Posted by koncretekid
The drive to Colorado takes about 40 hours over 3-4 days and I do 90% of the driving. Satellite Radio and NPR and the GPS are your friends along the way.
I'm afraid that, for me, the thought of a drive that would require endless hours and miles of Interstate makes me numb. Endless hours and miles on a 90-year old rigid-framed bike, that's completely different...

Originally Posted by koncretekid
my 5' x 10' enclosed trailer
It's just a single snapshot, but a quick look at the regional Craigslists just now found that used 5x10 enclosed trailers seem to sell for significantly more than 6x10. But, I think either size would be fine for the task should I go for a trailer rather than a crate.

Originally Posted by koncretekid
packing up and trying to allow for all possible spares and tools more stressful than the actual drive.
I can well understand that. I've been setting aside supplies and special tools for the Ariel as I use them or as they come to mind, but general purpose tools (BSW sockets, adjustable spanners in various sizes, etc.) have to remain in use so the worry is not forgetting any of them when it comes time to pack.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 11/11/17 5:01 pm

Originally Posted by Magnetoman
just knowing that a wide range of tools and spares are waiting at the motel that evening would relieve pressure so would be well worth having even if I never had to use them.


In that case I think you almost have the answer.

Driving it yourself is out.

You need to "do the math" on the crate vs trailer decision taking care to look at the price difference on weights, shapes and sizes of different boxes vs trailers.

Then work out just how much stuff you want/need to take to have the peace of mind.

Compare the list of stuff with your various box options and make the final decision.


John


Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/11/17 7:12 pm

Originally Posted by George Kaplan
Then work out just how much stuff you want/need to take to have the peace of mind.
It's not a question of if there will be mission creep as I assemble items for this event, it's a matter of how successful I will be keeping it to a manageable level.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 11/12/17 9:47 am

Originally Posted by Magnetoman
It's not a question of if there will be mission creep as I assemble items for this event, it's a matter of how successful I will be keeping it to a manageable level.


Ain't that the truth!

So it might be a "chicken and egg" thing. Work out your box/trailer options and also work out your list of stuff to take in parallel. Then compare the two. If you cant fit all of the stuff in the preferred box option then look at the next size up. Rinse and repeat. Once you get to the biggest box or trailer that you are willing to take then that is the limit of stuff to take.

Its a balance that only you can decide on and depends on too many variables to list.

Its a balance (on a much smaller scale) that I am pondering at the moment for a trip I am planning next year. I had planned to take an old bike in my panel van with lots of stuff but it turns out that the ferries are booked up for vans on the dates that I am going however they do have bike space. So now I have the choice of an old bike with less stuff or a newer bike with more stuff. My preference is an old bike with lots of stuff. Only I can figure out what is acceptable for me. Much like your own dilemma although yours is harder.

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/14/17 6:48 pm

Disappointment arrived in yesterday's mail in the form of a package from Draganfly. Two of the three items in it were incorrect, although to Draganfly's credit they immediately acknowledged the problem and offered to refund the return postage.

One of the items was a 19T sprocket for 1927-30 Burman Q gearboxes that I was going to modify using a larger sprocket I already had purchased. Unfortunately, the sprocket in the package was a "simple" one rather than the more complicated Burman sprocket with an integral hub as part of it. They now realize their entire stock of these sprockets is incorrect so, if they don't find a source of proper ones in the next month or so, I'll have no choice but to modify my current sprocket. I always like to have a backup in hand when modifying something so that I have the option of returning to original condition if I want, or in case things go badly, but that may not be an option.

They've also fixed a problem on their web site that until today when you clicked on Part No. 25-Q for that sprocket a "Related Item" showed up as gasket set 00-3312. Since it was "related" I naturally assumed this was for the Burman Q box so I ordered it. However, thanks to a programming error, it was for the BSA A65 gasket set I found when I opened the package.

Thanks to them paying for the return postage I won't be out any money, but I'm left without two items I had mentally crossed off my to-buy list.
Posted By: Richard Kal

Re: 1928 Ariel Model C - 11/14/17 9:56 pm

I had the same problem re 19T sprocket from Draganfly; the wrong style / type arrived.

The solution was straight-forward; purchase a 19T industrial sprocket with integral hub, and machine down the hub to copy the original sprocket (easy peasy for you, Magneto man). Then I had the internal splines wire cut.

Result; perfect copy of original sprocket for reasonable cost (and a left-over sprocket from Draganfly).
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/15/17 12:16 am

Originally Posted by Richard Kal
industrial sprocket with integral hub, and machine down the hub to copy the original sprocket
Great idea, thanks for suggesting it. An appropriate one of the "Machinable-Bore Sprockets for ANSI Roller Chain" on the McMaster-Carr web site looks ideal.(*) I can mount it to the rotary table to broach the necessary splines once I have the gearbox apart and make the necessary measurements. The hub looks like it might be shorter than the proper Burman one, but that would be simple to solve with a spacer. Again, thanks very much.

(*) 23T now on order. 3/4" ID bore x 3" width.
Posted By: Richard Kal

Re: 1928 Ariel Model C - 11/15/17 3:29 am

You shouldn't need a spacer. The standard industrial hub here in Oz has a substantial boss (no pilot bore); all for $30 - $40.

The blank hub is a Fenner 10B1-19
Posted By: Richard Kal

Re: 1928 Ariel Model C - 11/15/17 3:45 am

Just to confirm that the part no is 10B1-19FEN.

If you need a data sheet just email me off-line, this forum is too much hard work for posting attachments or pics.
Posted By: kommando

Re: 1928 Ariel Model C - 11/15/17 9:51 am

This company will induction harden the teeth on sprockets for you, there must be an equivalent company in the US.

http://www.lakehurstpt.co.uk/
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/15/17 3:50 pm

Originally Posted by Magnetoman
(*) 23T now on order. 3/4" ID bore x 3" width.
Originally Posted by Richard Kal
The standard industrial hub here in Oz has a substantial boss (no pilot bore);
Originally Posted by kommando
This company will induction harden the teeth on sprockets for you,
Thanks guys. Six hours after I placed an order for a 22T version of the type of sprocket suggested by Richard an email from Draganfly arrived. They had contacted the supplier (that turned out to be the Ariel Owners Club) and were told it actually is correctly made for the Burman splines but it also requires a spacer, for which the club has been meaning to find a manufacturer as well.

I hadn't yet packaged the parts to send back to Draganfly so to work with I have:

-- the original 19T Burman sprocket that's on the gearbox now (I'll leave it as-is).
-- a reproduction 19T that also requires a spacer, to serve as a donor of its splines and a 22T sprocket to serve as a donor of its teeth.
-- an industrial 22T that requires boring to size and broaching six splines (and facing off its boss to be the correct length).

I'll be keeping the Draganfly sprocket, although overall I expect it would be easier for me to broach those six splines in the industrial sprocket than it would be to graft two sprockets together. Once the industrial sprocket arrives I'll measure the hardness of the teeth and bore/boss of each to know if any further hardening is required.




Attached picture IMG_6649.JPG
Posted By: Alan_nc

Re: 1928 Ariel Model C - 11/16/17 9:25 pm

So do you think this 'procedure' (and money) you are going through is multiplied by the number of entrants in the event? If so, this event has a real impact on the Vintage Motorcycle Industry.

So it would seem that the event is limited to engineers/machinists with quite a bit of free time and some financial resources. Of course I'm sure there will be at least one entrant who will buy his bike on Ebay a couple of months before the start date and just show up on the starting line pulling the bike on an open trailer.

All this to say: I am amazed at the care and planning you are taking. I really do hope it pays off.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/17/17 4:12 am

Originally Posted by Alan_nc
So it would seem that the event is limited to engineers/machinists with quite a bit of free time and some financial resources.
Luckily, I know how to engineer and machine things, don't have lots of free time but have reasonable time management skills, and am not wealthy but know how to spend money anyway. Although this will take a fair amount of time and money before it's done, I'm trying to squander resources "intelligently" rather than throwing money at the preparations. Or, taking the Walt Disney approach to preparations ("wishing will make it so").

Originally Posted by Alan_nc
I am amazed at the care and planning you are taking.
I'll take that as a compliment...

Stated as follows, "Solve the problem of riding a 90-year old bike 4000 miles across the U.S. while minimizing the total cost as well as the chance of breakdown, while also being prepared to repair a wide range of breakdowns that might happen anyway," it can be seen as an optimization problem with constraints. Given similar skills and constraints I think someone else would approach this pretty much as I am. Of course, a more reasonable person would recognize this as an idiotic problem to want to solve in the first place, and would spend their time and money on something less foolish.

Originally Posted by Alan_nc
I'm sure there will be at least one entrant who will buy his bike on Ebay a couple of months before the start date and just show up on the starting line pulling the bike on an open trailer.
I'm pretty sure that has happened more than once in the past so no doubt you're right. Although the odds of such a bike not breaking down aren't good, someone with this "Walt Disney approach" to the Cannonball could get lucky.
Posted By: Alan_nc

Re: 1928 Ariel Model C - 11/17/17 9:47 am

The whole comment was meant as a compliment.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/17/17 6:34 pm

Originally Posted by Alan_nc
The whole comment was meant as a compliment.
Just teasing. I took it as such. Thanks for the post.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/18/17 4:00 pm

In a second stroke of luck I've now found another person with an original Ariel piston. This one is a new, in the box, complete +30 piston assembly in Canada and it weighs 512 grams compared with the 507.2 grams of the used, standard bore piston assembly that previously turned up in Australia. I can't thank these two people enough.

Correcting for the 6.5 grams that I calculate the extra 0.030" x 3" "skin" on this +30 Hepolite/Heplex 4950 weighs (less the two 1"-dia holes for the pin), if it had a standard bore it would have weighed 505.5 grams. This is within 1.7 grams (0.06 oz.) of the used Australian piston assembly so is near-perfect agreement. Since the used Australian piston had some carbon on it I'm settling on 506+/-1 gram as the official weight of a stock Hepolite piston assembly (piston, rings, gudgeon pin, and Al plugs) for a 1928 Ariel Model C.

Having now measured twice, I can now cut the flywheel once with confidence. But, before cutting, I will use this weight to determine the original balance factor used by the factory once I disassemble the bottom end and have the crankshaft on the rollers.

The rollers have sensitivity equivalent to 0.6 grams at the 4" radius of the flywheels so combining this with the ~1.7 gram uncertainty in the weight of the stock piston I will be able to determine the original balance factor used for my engine to better than 1%. Assuming I don't find "fresh" rebalancing holes in the flywheels made after it left the factory...



Attached picture IMG_6645.JPG
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/20/17 5:10 am

The list of riders was sent to us tonight. Some numbers in the sequence are skipped but a quick count shows approximately 116 entries of which 11 will be on British bikes, all but one of which is a single. There are 4 Triumphs, 3 Nortons, and 1 ea. Ariel, Brough-Superior, BSA and Rudge.

Thirteen of the entrants aren't from the U.S. (if we count Canada as a foreign country...). The guy who showed up on Britbike some months ago saying he bought a BSA Sloper to use, and then quickly went quiet, isn't an entrant since only one BSA is on the list and it's entered by someone from South Africa.

Pre-'19 and pre-'29 bikes will be in separate classes so it looks like there will be 8 other British singles in the same class with me.
Posted By: KevinN

Re: 1928 Ariel Model C - 11/20/17 10:20 pm

Originally Posted by Magnetoman
The list of riders was sent to us tonight. Some numbers in the sequence are skipped but a quick count shows approximately 116 entries of which 11 will be on British bikes, all but one of which is a single. There are 4 Triumphs, 3 Nortons, and 1 ea. Ariel, Brough-Superior, BSA and Rudge.

Thirteen of the entrants aren't from the U.S. (if we count Canada as a foreign country...). The guy who showed up on Britbike some months ago saying he bought a BSA Sloper to use, and then quickly went quiet, isn't an entrant since only one BSA is on the list and it's entered by someone from South Africa.

Pre-'19 and pre-'29 bikes will be in separate classes so it looks like there will be 8 other British singles in the same class with me.


I was excited to see your name on the list, Charles. In my estimation you are a top contender in the modern bike category ;-). I would like to add one statistic to your list; there are four riders from the state of Nebraska. In fact, we all live within about a 20 mile radius!

If anyone would like to view the full list, I have posted it here:
http://advrider.com/index.php?threads/powerplus-or-bust-eh.996958/page-35#post-33699959

Keep up the good work Charles, I'm following your work and enjoying you posts very much!

Thanks-




Kevin
97


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Posted By: old mule

Re: 1928 Ariel Model C - 11/20/17 11:06 pm

four Triumphs and an Ariel? Now my loyalties are in for a splittin'.
Posted By: Rich B

Re: 1928 Ariel Model C - 11/21/17 12:39 am

I am thinking now there can be a side challenge during the Cannonball........

Kevin representing Adventure Rider versus Magnetoman representing BritBike.com!

I will be cheering you both on.

And if the route comes through Ohio, I will shake your hands
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/21/17 1:57 am

Originally Posted by KevinN
In my estimation you are a top contender in the modern bike category ;-).
I'm following your work and enjoying you posts very much!
Kevin, thanks very much. I hope you're right, and that my goal to finish somewhere in the top 10 of British singles isn't too unrealistic...

Originally Posted by old mule
four Triumphs and an Ariel? Now my loyalties are in for a splittin'.
You've forgotten that the statute of limitations on brand loyalty ends on bikes earlier than 1945 so you would be guilt-free to root for another brand as long as it was made before then.

Originally Posted by Rich B
I am thinking now there can be a side challenge during the Cannonball........
Kevin representing Adventure Rider versus Magnetoman representing BritBike.com!
Except Kevin has two cylinders as well as prior experience completing the most recent Cannonball with full points. Can we give him a, say, 2000 mile handicap?...

Over the past two days I put away all the tools that somehow ended up on the lift under the Catalina, cleared off other horizontal spaces that had managed to be covered with clutter, and generally cleaned up in preparation to start work again on the Ariel.

As a first step I assembled the balancing wheels on a stand I had previously made for them to use when balancing wheels. This will hold the crankshaft high enough for the rod to hang down for balancing once I extract it from the cases. Once it's out of the cases I'll be able to weigh the small end and then make a weight that balances ~60% of that plus the original piston. This way I can then add additional weight from a standard set that starts at 5 g to get very close, with the last few grams supplied by a piece of wire or whatever that I'll weigh on a calibrated scale. The total weight hanging from the rod when finished will let me calculate the original balance factor. Assuming, as I wrote before, I don't see any evidence the flywheels might have been altered since leaving the factory.

I can feel no play at all in the big end bearing so at this point my feeling is to leave it alone since I don't know what I'd learn by disassembling the crank (other than learning I shouldn't have disassembled the crank...). I may change my mind once I have it out and see how well assembled and aligned it is. On the other hand, having the rod separated would make it easier to install and size the small end bush.

[to be continued]
Posted By: gREgg-K

Re: 1928 Ariel Model C - 11/21/17 3:20 am

Originally Posted by Magnetoman
[<SNIP>I can feel no play at all in the big end bearing so at this point my feeling is to leave it alone since I don't know what I'd learn by disassembling the crank (other than learning I shouldn't have disassembled the crank...). I may change my mind once I have it out and see how well assembled and aligned it is. On the other hand, having the rod separated would make it easier to install and size the small end bush.
[to be continued]


MM, I'd encourage you to split the crank and inspect the big end. My experience is the lack of play is a good sign regarding the lack of wear, but it is not a definitive indicator of health. Here, I'm thinking in terms of pitted rollers, or line corrosion on the bearing faces of the outer race or crankpin. I went through this a few years ago when I inspected 4 crank assemblies I had always viewed as perfect, and after splitting them, found none to be serviceable due to line corrosion.

This had happened despite years the engines had spent in storage, with their big ends submerged in a wet-sumped crankcase... submerged in dirty oil, contaminated with moisture and combustion by-products.

.. Gregg
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/21/17 3:32 am

Originally Posted by gREgg-K
I'd encourage you to split the crank and inspect the big end.
Sigh... But, I know you're right. Oh well, what's the point of having a 30T press if you don't get to mash things together once in a while? If I find bad rollers, that's one thing, but pray the crankpin isn't toast because replacements don't seem to be available on Amazon.com.
Posted By: kommando

Re: 1928 Ariel Model C - 11/21/17 7:26 am

Alpha Bearings have the 28 C as using the A5 big end bearing which was used on other models up to 53, so Amazon.co.uk is a better bet.
Posted By: RPM

Re: 1928 Ariel Model C - 11/21/17 2:27 pm

Definitely take it apart. Alpha rebuilt the crankshafts on the Nortons. They built new flywheels and shafts for the 1915 last year. Rebuilt both cranks that I am working on now. All the bearing that came out looked a little rough but felt good.

I also vote for the truck and trailer for the trip. Trailer will keep your important stuff dry when it rains.

We are bringing a tig welder. The 1915 broke the handle bars on the trip last year. Richard rode it 35 miles with the left side handle bar hanging on by the clutch cable. He held the broken bar and pulled the clutch then removed his right hand from the good side of the the bars to shift. He did a great job. We were in the paddock for a few minutes when a local said his buddy had a shop about 5 minutes away with a welder. One phone call and we had it repaired in a few hours. We want to be ready this time so we are bringing our own welder. A small lathe also. Since we have three bikes we need a ton of stuff.
As I said before you are welcome to use our welder at any time.

I am making a little progress on the Nortons. Since the handle bars broke on the 1915 we are making new one. I bought some Flanders drag bars and cut them in half to weld into the new stem we made. Also did the same with some superbike bars for the 1924 Norton I am riding. ( The list is wrong as I changed bikes. The Big 4 will be the back up bike) It had some weird almost clubman style bars that were to low for me.

I was cleaning the cases on the 1924 and realized they were painted. I was not planning on blasting them but did not want paint on them. I put them in the blaster and soon realized why they were painted. At one point it its life the motor had sat in the dirt. Moist dirt. You could see were the motor sat in the dirt it had deteriorated the alloy cases. Big pitted area on drive side case. Some one had filled the pitted area with bondo and sanded it smooth. Then painted the cases silver. It was all cosmetic damage so I did the only I could think of. I filled it with bondo and painted it silver. It was just to big of an area to weld in pits. To much heat on case.

Everything for motors on the 1923 and 24 are in house except the valves.They are being made right now.

I also like the idea of the drip feed chain oiler. I think we are going to make one each bike.

The Cannonball has got me excited about motorcycles again. After 30 years you can get a little burnt out in the motorcycle business. Looking forward to the trip.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/21/17 2:54 pm

Originally Posted by kommando
Alpha Bearings have the 28 C as using the A5 big end bearing
Bingo! It's on Alpha.com (well, Alpha-Bearings.com) rather than Amazon.com. Thank you very much. I wonder if they offer free same day delivery to their Prime members like Amazon does.

I've now written to them to ask if they have the A5 in stock(*) since sometime companies don't bother to delete old part numbers even when no longer available. If they do still have them it will be easier, psychologically, when disassembling the crankshaft if I know ahead of time there's a workable Plan B if necessary. Again, thanks.

(*) I quickly heard back from them that "We do currently have stock available and they cost £160.00 each."

Originally Posted by RPM
Alpha rebuilt the crankshafts on the Nortons...
As I said before you are welcome to use our welder at any time...
The Cannonball has got me excited about motorcycles again. After 30 years you can get a little burnt out in the motorcycle business.
First, thanks for that offer. I hope I won't have to take you up on it, as I also hope you won't need any of my electrical knowledge. But, it's available if you do.

Doing all the work on the Ariel is part of the enjoyment for me, which includes rebuilding, balancing, and truing the crank. For me, the Cannonball is the "opportunity" to ride more than I've allowed myself to over the years. All too often I've skipped opportunities since I always could do it later. Eventually, everyone runs out of laters. I put 'opportunity' in quotes in the hopes it turns out to be that rather than a curse.

Originally Posted by Rich B
cabinets/shelving.. Some 12v LED lights, an onboard battery, inverter, and Honda generator
I sense mission creep taking over...
Posted By: Rich B

Re: 1928 Ariel Model C - 11/21/17 3:01 pm

I would also go with a truck and trailer. An enclosed trailer is a life saver in dealing with vintage bikes.

Arranged properly and with some cabinets/shelving, it amazes me how much I can cram into 6’ X 10’. Some 12v LED lights, an onboard battery, inverter, and Honda generator does wonders.

Posted By: gREgg-K

Re: 1928 Ariel Model C - 11/21/17 3:30 pm

Originally Posted by RPM
<SNIP> Everything for motors on the 1923 and 24 are in house except the valves.They are being made right now.

Re: Valves - I need some valves made, too. Do you mind sharing the name of the company you are using for yours?

Thanks,
.. Gregg
Posted By: RPM

Re: 1928 Ariel Model C - 11/21/17 4:43 pm

Valves being made here.

http://www.ferrea.com/

Found valve guides in Germany. Valve springs in Australia. We looked at updating to a more modern spring but seat pressure was just to high on everything that was close to fitting.
Posted By: KevinN

Re: 1928 Ariel Model C - 11/22/17 3:06 am

Originally Posted by Magnetoman
Originally Posted by KevinN
In my estimation you are a top contender in the modern bike category ;-).
I'm following your work and enjoying you posts very much!
Kevin, thanks very much. I hope you're right, and that my goal to finish somewhere in the top 10 of British singles isn't too unrealistic...



Don't sell yourself short, MM. I think you'll do well. Historically the Brit bikes and the Hedstrom (1915 and older) Indians, despite valiant efforts, have not placed with perfect scores. I'm looking for that to change next year, based on the level of preparation that I see happening now on both those fronts.




Kevin


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Posted By: KevinN

Re: 1928 Ariel Model C - 11/22/17 3:13 am

Originally Posted by Magnetoman


Originally Posted by Rich B
I am thinking now there can be a side challenge during the Cannonball........
Kevin representing Adventure Rider versus Magnetoman representing BritBike.com!
Except Kevin has two cylinders as well as prior experience completing the most recent Cannonball with full points. Can we give him a, say, 2000 mile handicap?...



No side challenge, Rich. I'll be rooting for Charles all the way. It's not that kind of contest. I'm in it for the fun this time.

And no need for a handicap Charles, even though your machine has the benefit of 12 more years of technological development.




Kevin


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/22/17 4:13 am

Originally Posted by KevinN
Don't sell yourself short, MM.
Shush, don't tell RPM or the others, I'm trying to sandbag them into complacency...

Originally Posted by KevinN
I'm in it for the fun this time.
Me too. I'll be riding with the goal of going the distance, having a good time along the way, and having the satisfaction of covering every mile -- fingers crossed -- on a 90-year old bike I completely rebuilt myself.

After about 15 min. of thought this morning I decided the risk of Alpha selling the last of the required crankpins (followed by an indeterminate production delay...) might be small, but it outweighed the ~$220 cost so I ordered one to have in case I need it. If I don't need it, I'll put it on the local Craigslist and let the nearby Ariel owners fight it out for the right to buy it.
Posted By: kommando

Re: 1928 Ariel Model C - 11/22/17 10:04 am

$220 more foreign exchange for the UK coffers.

Alpha do have that reputation for selling out just before you order and then taking an age to restock.
Posted By: RPM

Re: 1928 Ariel Model C - 11/22/17 2:25 pm

Here is a summary of what Alpha did to the 1924 Norton Crank. I do not have the machines or skill to do all that. Alpha has provided me with great service in past two years. They have done 6 crankshaft for me.


1 N3KSXF
1924 Norton flywheels fitted with silver plated steel caged big end bearing, new small end bush to suit pin in 26559 then aligned and trued.

Taper jig grind main shaft holes. Timing side was 0.005" out of round & drive side 0.020" out of round.

Supply and fit replacement drive side shaft

Supply and fit replacement timing side shaft

Grind flywheel outside faces & Ø's to allow jig grinding

Jig grind crankpin holes

Static balance assembly to suit 424 gm piston and 60%
This required 42gm to be removed at BDC from each wheel.

Good sub contractors are essential in the vintage motorcycle business. They are also getting very hard to find as they either retire or die.


Posted By: KevinN

Re: 1928 Ariel Model C - 11/22/17 4:50 pm

Originally Posted by RPM


Good sub contractors are essential in the vintage motorcycle business. They are also getting very hard to find as they either retire or die.




I'll second that. Big time.




Kevin


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Posted By: old mule

Re: 1928 Ariel Model C - 11/22/17 9:36 pm

Rich B., a HONDA generator??? How about a WWII Triumph gen set with those nice close-finned alloy barrels? And we could hot rod it with an Amal GP too.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/23/17 12:21 am

Originally Posted by old mule
How about a WWII Triumph gen set with those nice close-finned alloy barrels?
As Eleanor Roosevelt said to the RAF airman who was swearing at his generator set on the pitch dark air field, "It is better to light a candle than to curse the darkness."

When I got my balancing wheels a few years ago I machined a stand to hold them so as to place a shaft ~14-1/2" above the bottom so I could balance wheels complete with tires. Their sensitivity makes them overkill for this task, but they do a great job. The hubs on the Ariel's wheels are wider so I had to machine a ~2" spacer for the base to make room for them. Today, since the length of the Ariel's crankshaft is essentially the same as that of a BSA B33, I did a test fitting of a BSA crank and, as a result, machined a new base that's 2-1/2" narrower. If the Ariel crankshaft turns out not to fit for some unexpected reason I'll machine another base for it and keep the one I made today to use for any future BSA singles crankshaft balancing.

Further progress arrived in the mail a little while ago, in the form of the NOS +30 Hepolite piston from Canada I mentioned a few days ago. He donated this to the cause and wouldn't accept any payment, even for the postage. This makes him my first International Sponsor for the event.

As expected the clearance is a bit too large for the present bore. However, I'm going to investigate Swain Tech Coatings to see if they could apply a thick enough coating to take up the excess clearance without risk of flaking. Meanwhile, I confirmed its weight with my calibrated scale. The piston is from pre-cam-ground days so is round, and it has a slightly dished top so it's definitely lower compression than the piston that came out of my bike.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/24/17 3:54 am

There was a break in my Thanksgiving duties this morning long enough to make some measurements on the NOS +30 piston, and after the guests left this evening I was able to make some calculations.

The piston is quite accurately cylindrical, varying in diameter by no more than 0.0003" anywhere on it. The measurements were all 3.2450"-3.2453". Unfortunately, this means that at the top of the present bore, where the diameter of the cylinder is largest, the clearance would be an excessive 0.0151"-0.0154". Swain coatings lists 0.004" (i.e. 0.002" coating thickness) as the maximum reduction in clearance they can make with their coatings. Only if they could increase this to ~0.010" (0.005" thickness) would I be able to use this piston. I assume Swain will be closed tomorrow but I will call them next week. However, I'm not optimistic a coating that thick wouldn't flake.

With accurate measurements of its dimensions and weight I was able to make a more accurate estimate of the weight of a stock piston. This reduced my estimate from the "Canadian" piston by precisely 2 grams (0.07 oz.). Taking the average of the Australian and Canadian piston weights, the new "official" weight of a stock Hepolite piston for an Ariel C is 505+/-2 grams (17.81+/-0.07 oz.).

A one gram difference in the average is a very minor correction to the weight I listed in a previous post and it will make a trivial change to the final balance factor I determine. But, there's no point in having accuracy and not using it, especially since it will save anyone else from having to go to this trouble in the future.
Posted By: RPM

Re: 1928 Ariel Model C - 11/24/17 6:48 pm

Have a sleeve made.

https://www.lasleeve.com/

They sleeved the cylinder on the 1923 and bored the cylinder on the 1924 oversize. The cylinders would not fit any of the fixtures for my boring bar and for what they charged to bore the blind hole I could not have made a new fixture.
Posted By: gavin eisler

Re: 1928 Ariel Model C - 11/24/17 7:38 pm

This site, http://www.auto-cycle.co.uk/parts.htm , lists " Unsorted box of Ariel pistons " in their inventory. You may have looked there already, thought I would mention it just in case.
I have a Goldstar riding buddy who gets stuff from them ( they have Eddie Dow's old stock). He rates them highly.
They wont be open till Monday but they do answer E mails in shop hours. You might get lucky?, I noticed the Alpha bearings site also lists a few Ariel single pistons but none as old as your model. Fingers crossed , a plus 40 might turn up.
They have NOS home gas tanks for my 71 , at a fair price , which I was delighted to find.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/25/17 12:41 am

Originally Posted by RPM
Have a sleeve made.
With a sleeve I could use an original non-cam-ground two-ring piston (see below for clearance discussion). That has its pros and cons. The physical act of sleeving has risks, as does shipping things back and forth. The sprocket I ordered ten days ago from McMaster-Carr to modify for the gearbox won't be delivered until next Tuesday, if then. UPS decided it needed to be shipped all the way to Atlanta and then tour the South before giving it to me, with the last recorded sighting in Mississippi. I have to regard parts like the barrel, head, etc. as irreplaceable since if they go missing there might not be time to find a substitute (although, see below).

Originally Posted by gavin eisler
A pretty substantial package of Gold Star parts from them arrived today. I didn't think to ask about old Ariel pistons. However, thanks to having the weight of an original piston, and two +60 aftermarket cam-ground pistons with oil rings in hand, I think I'm going to go in that direction.

I remeasured the later, cam-ground +30 Hepolite piston that came in my engine. Side-to-side, the dimension that will have the greatest thermal expansion, it is 3.2460", roughly the same as the diameter of the cylindrical "Canadian" +30 piston (3.2450-3.2453"). However, for the front-to-back thrust faces it is 9.7 thou. larger at 3.2557". Since the present bore of the cylinder is 3.2604" at the top the clearance (front-to-back) was 4.7 thou. with the piston that came in the engine.

This raises the question of how much clearance should be used on a non-cam-ground piston? I looked in my 17th, 1935, edition of Dyke's Automobile and Gasoline Engine Encyclopedia and they call for only 0.003" - 0.0035" for Al pistons in this bore size. While that's for water-cooled engines, air cooled won't be that much larger. However, luckily it looks like I won't be playing that particular version of the 'Seize Your Piston' game, instead opting for modernity.

Today I disassembled the bottom end, which meant first removing the timing case. Lacking anything nearly as detailed or accurate as even a Haynes manual, I proceeded slowly and took lots of photos. After removing the sprocket that drives the magneto chain, six screws obviously hold the timing cover in place. The problem in these situations always is, is there a seventh non-obvious screw? Although it didn't budge, after convincing myself there couldn't be any other fasteners holding it, I used the same tool I had made for this purpose for Gold Stars, based on an adjustable-height leveling screw, to carefully press the cover hard enough to get it to move, at which point it came off with a little wiggling.

There's a '.' stamped between teeth in the cam gear with that space directly over a tooth in the crank pinion when the engine is at TDC on the compression stroke. According to Ariel literature (which might be for '29) there should be a corresponding '.' in the pinion, but there isn't. The pinion has three slots broached in it, one directly under the tooth that's under the '.' in the cam gear, with the other two slots offset from being directly under teeth. I marked the pinion with paint and then stamped a '.' after I removed it using a 3/4" A/F socket on the left-hand nut. Funny how a variety of fasteners find their way onto a bike after 90 years, isn't it?

The cam spindle has quite a bit of pitting and scoring in it, as do the cam base circles. There's no pitting in the cam lobes which implies they've been reground. Evidence of that grinding is present. I'll measure the roughness and then polish them with an appropriate grit

The drive side bearing, marked 'Ace' RMS8-2RS, is 2.5" OD, 1" ID and 3/4" thick. It slips in and out of the case easily (too easily...). Its OD is 2.5000" but I haven't yet measured the ID of the housing. In any case, I'll try to find a name-brand bearing to replace it with and deal with the clearance issue after I have it.

Once I removed the crankshaft I found a 7/8" shaft on the timing side and a 1" shaft on the drive side so I decided the easiest way to deal with this for balancing is to buy two bearings with matching ODs. I could have made bushings myself but it would have taken quite a while to make them to the necessary precision (the bores would have to be precisely concentric with the ODs). As far as I can tell it appears only an original pair of balancing holes are in the flywheels, which means I will be able to determine the original balance factor.

Although I'll wait for the bearings to arrive before making precision measurements, I did take the time to mount the crank between centers in my lathe. Assuming the center drillings are good (and they do look good) the TIR of the drive bearing surface is 0.004" and of the timing bushing surface is 0.0055". The wobble of the drive-side flywheel is 0.015" and of the timing-side flywheel is 0.007". If these values hold up when I make better measurements, they're pretty unimpressive.

Given the condition of the surfaces on the cam, even had I not already ordered a new crankpin I would do so now, before disassembling the crank. Tomorrow I'll polish the cam, inspect (and probably polish) the two shafts on the crank, and then measure clearances of the timing side bushings to see if I need to make new ones.

An interesting discovery I made today is that a BSA B31 (probably a ZB31) cylinder I have on the shelf is a perfect fit on the Ariel bottom end. The cylinder is 1/8" shorter than that of the Ariel but that could be easily dealt with using a compression plate. Conveniently, several months ago I bought a 0.093" Ariel compression plate from Copper Gaskets Unlimited so they already have the pattern for making another one from 0.030" if for some reason they couldn't make a full 1/8". The 71 mm bore of a B31 cylinder can't be taken out to the 88 mm of a 500 cc BSA, but the 7 mm longer stroke of the Arial means it wouldn't have to be. The spacing between bolt holes at the top is ~0.2" different, but that could be solved by plugging the existing holes and tapping new ones. Also, the cutout for the pushrods is slightly narrower but that would be easy to enlarge. Anyway, should the Ariel cylinder fall and shatter this means that it would be a major headache, but not necessarily a disaster.

Offline someone asked me about the precision to which I quote measurements, wondering if I really did mean it.

If I quote a dimension to, say, 0.0001" it means I've checked the relevant micrometer or dial indicator with a calibration rod, ring gauge, or gauge block set (depending on the instrument) before making the measurement so it really does mean 0.0001". That said, to conserve energy in the summer I set the thermostat in my garage to 78 oF when I'm working in it (88 when I'm not) and in the winter to 68 (50 when I'm not). This means the instruments and parts usually haven't equilibrated to the "official" 68 oF (20 oC) for 24 hours for a "true" measurement so there will be some small amount of differential thermal contraction between the steel of the micrometer and the Al (or whatever) of the part that depends on the size of the part. Any resulting error in the quoted dimension is nearly always smaller than anything relevant for motorcycle work, but where it might be relevant I'll mention it, and in cases where it really does matter I will have done a proper measurement at 68 oF.

In the case of weights, such as that of the piston, I have three electronic scales covering different ranges that I calibrate with weights of accuracy better than the resolutions of the scales. Similar comments for voltage, resistance, etc.



Attached picture IMG_6245.JPG
Posted By: George Kaplan

Re: 1928 Ariel Model C - 11/25/17 9:13 am

Hello MM, great progress on the Ariel. Re the comments on the accuracy of measurements I seem to remember that you covered the topic previously when you wrote the guide to magneto rebuilds elsewhere on this forum so if anyone is interested in how you do things and what level of accuracy that you aim for then that thread is not a bad start.

I do realise that previous threads are afflicted by the Photobucket hot linking problem but if people cant see your pictures then they should download the patch for either Firefox or Chrome and all will be revealed so to speak.

The comments on the BSA cylinder being close to your Ariel are interesting. Perhaps there is another cylinder from another bike that is even closer if the Ariel cylinder doesn't work out or you feel like you need a spare? I have heard of people substituting cylinders on other bikes in the past so it is certainly a possibility. There must be enough willing old bike people on here to get some dimensions from other cylinders pretty easily. That said a suitable plus 0.040" piston would seem like the best solution.

Keep up the good work I, like a few others on here, will be vicariously preparing for and riding the Cannonball with you.

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/25/17 4:40 pm

Originally Posted by George Kaplan
Re the comments on the accuracy of measurements I seem to remember that you covered the topic previously when you wrote the guide to magneto rebuilds elsewhere on this forum ...
I'm sure that not for the last time I'll forget and repeat information I've typed elsewhere (perhaps even in the previous post in the same thread...).

Originally Posted by George Kaplan
Perhaps there is another cylinder from another bike that is even closer if the Ariel cylinder doesn't work out or you feel like you need a spare
I don't know what prompted me to put that BSA cylinder on the Ariel yesterday. Probably because I'm interested in the similarities between this engine and Val Page's design of the BSA engine a decade later from which the Gold Star developed so that is always in the back of my mind. As homage to the lineage, and thanks to Kurt Fischer, the Ariel will be wearing a Chronometric listed as having been used on 1952 'Road Model' Gold Stars. Anyway, I wasn't thinking in terms of a spare cylinder when I placed it on the engine. Although, come to think of it, a B34GS cylinder and DBD head could give the bottom end of the Ariel some serious h.p. to recon with...

Speaking of the bottom end, given the loose fit of the ball bearing in the drive side case it can't be counted on to locate the crank. Absent a circlip or other locking mechanism even a press fit in the case wouldn't be sufficient, so what Val Page used for this purpose is a fairly large OD (~1.3") bush on the timing side against which mates a machined surface on the crank. That's another surface I'll need to polish.

The oil pump causes me some concern. It is a simple plunger pushed down by a cam on the camshaft, and pushed back up again by an internal spring. Relying on only a spring to operate it in one direction means that if the plunger binds only slightly in the housing the meager oil flow will cease.

The other aspect of oiling that I'll delve into today are the two "reed valves" that bring oil mist from the crankcase into the timing chest. Both seem to be fine but I'll take them apart to be sure there are no hidden issues. They are based on thin pieces of metal trapped under caps that are press fit into the case so I'll have to figure out how to un-press-fit them, which might not be easy since they are fairly small.
Posted By: kommando

Re: 1928 Ariel Model C - 11/25/17 6:57 pm

Quote
I do realise that previous threads are afflicted by the Photobucket hot linking problem but if people cant see your pictures then they should download the patch for either Firefox or Chrome and all will be revealed so to speak.


If only it was so simple, the fix is currently not working, so we await the next version which will no doubt be got at by PB after a few weeks.

Ah ha,

These are the latest fixes as the original does not work now.

https://chrome.google.com/webstore/...x/kegnjbncdcliihbemealioapbifiaedg?hl=en

and

https://chrome.google.com/webstore/...g/ogipgokcopooepeipngiikdkpmcpkaon?hl=en

I now have all 3 in place and seeing the PB images again.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 11/25/17 7:28 pm

Originally Posted by Magnetoman
[quote=George Kaplan] The oil pump causes me some concern. It is a simple plunger pushed down by a cam on the camshaft, and pushed back up again by an internal spring. Relying on only a spring to operate it in one direction means that if the plunger binds only slightly in the housing the meager oil flow will cease.


Depending on your level of concern you could fit either an oil pressure gauge or an oil pressure indicator "button" similar to the 1950's Triumphs and, I believe, a few other makes. However adding this might not be simple (I am not familiar with the Black Ariels so not sure if there is a suitable pressure take off point) and adding a gauge or indicator would obviously not conform to the KISS principle.

However the return spring that you describe does not seem ideal. However how often does an oil pump bind? I have no idea if any other bikes used such an arrangement. If no other Black Ariel owners have reported problems then maybe its not such an issue?

Originally Posted by kommando
[quote]If only it was so simple, the fix is currently not working, so we await the next version which will no doubt be got at by PB after a few weeks.


I have Firefox v54 (64 bit) with the latest add-in and I have just checked various threads that I know had the Photobucket problem and I can see all of the pictures.


John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/26/17 1:52 am

Originally Posted by George Kaplan
Depending on your level of concern you could fit either an oil pressure gauge or an oil pressure indicator "button
It would be possible to tap into the gallery but it would not look pretty and I'm not sure how much good it would do unless the gauge was on the handlebars where I could glance at it frequently. However, in a real sense I already have a gauge, in the form of the oil drips in the sight glass on the tank. If the drips stop dripping, the pump has stopped pumping (or I forgot to fill the tank -- either way, the same effect on the engine). Unfortunately, since there's no realistic way to re-engineer the oil pump I'll have to live with its design and hope it doesn't bind.

I made a lot of progress today, some of which is visible. The cases were pretty clean but I soaked them in my new-favorite mix of diesel and Gunk anyway and spent some time removing old, hard joining compound remnants. There are two small holes that allow oil to get to the bushes and they could easily be blocked by a wayward chip of debris.

Measured roughnesses (Ra in microinches) of the various shafts ranged from ~24-30 for the timing side of the crank, to ~125-135 for the outside shaft of the camshaft due to pitting. Ideally, all would be less than 10. In the case of the camshaft the roughness value is deceptive in that what matters most is the roughness on the plateaus between pits since that will be the bearing surface. The pits represent absence of material, i.e. valleys between plateaus rather than between peaks.

All three bushes in the timing side have clearances ~0.003-0.004", whereas they should be no more than 0.001", so they'll have to be replaced. If I can't buy them I'll have to make them.

There are no locating dowels in the crankcase halves so it is possible to assemble them with a slight twist due to the clearance holes for the 5/16" and 3/8" studs. This would result in small steps at the front and back of the crankcase mouth. So, I faced a piece of 4"x4"x1/2" scrap Al and drilled the necessary four holes spaced 3-3/8" to use when assembling the two halves. After doing this I confirmed on a surface plate that the machined surface was still flat.

Starting with a 1"-dia. rod for the drive side I machined one end of it 7/8"-dia. for the timing side. I then bolted the cases together with this rod protruding from either end, using the flat plate I had just made to ensure the cases went together with no twist. When done I put the cases on the surface place, shimmed so the rod was level, and then measured the side-to-side tilt of the crankcase mouth.

It's no problem if a cylinder tilts slightly fore or aft but if it's tilted sideways the piston has to slide back and forth on the gudgeon pin to follow that tilt on each revolution. The crankcase mouth isn't perfectly smooth but it was no problem to determine that it tilts with respect to the crankshaft axis by ~0.045"-0.050". Since the stroke is ~3.7" this means the piston has to slide side-to-side by approximately the same ~0.045" twice on every revolution. Knowing this I'll now remove the studs and followers from the case and mount the crankcase on the mill indexed to the crankshaft axis in order to face the mouth.

Since the crankshaft was out of the engine I oriented it so the rod was horizontal and measured the weight of the small end. I won't be able to do this properly until the crank is apart, but this figure will be close enough for present purposes. Adding that 264 grams to the weight of the complete piston assembly that was in my engine when I bought it I get 730 grams. Doing the same for the original piston that came in the engine 90 years ago results in 769 grams. For the purposes of making an estimate, assume the final balance factor comes out at 66%. This difference of 39 grams in the weights of the two pistons means a difference of 26 grams at the flywheel from the value Ariel decided it "should" have when they determined the balance factor. Plugging 26 grams into a calculation, this weight rotating at a diameter of 8-1/4" results in an additional oscillating force of 168 lbs. at 5000 rpm beyond that which it would have had. If the engine is at 3000 rpm it's still an additional 60 lbs. hammering at the frame and the rider. This is why I'm been spending the effort required to "properly" balance this engine with whatever piston I end up using.
Posted By: chaterlea25

Re: 1928 Ariel Model C - 11/26/17 1:42 pm

Hi MM,
Earlier you announced that the drive side main was "loose" in the case
I would "fix" that problem first, then check that the timing side bush is concentric with the case bore,
I would align the cases as best possible and then ream two of the bolt holes,
Then make dowels to suit them so reassembly accuracy can be repeated
Correct any misalignment across the main bearing housings, Fit drive side bearing, then line bore the timing side bush to it
I would do all this before correcting the cylinder face
I would think that 0.001in. is too tight for the cam bushes, this is a total loss lubed engine you need "space" for the oil to get into the bush bores

John

Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/26/17 6:36 pm

Originally Posted by chaterlea25
... the drive side main was "loose" in the case
I would "fix" that problem first, then check that the timing side bush is concentric
Correct any misalignment across the main bearing housings, Fit drive side bearing, then line bore the timing side bush to it
I would do all this before correcting the cylinder face
Thanks for mentioning this. Even though I said I would "now" face the mouth I meant now it would get added to my list of things to do. I'm deliberately taking this slowly to try to avoid making any permanent changes like this in the wrong order. One reason I write in some detail about what I'm doing is in the hopes someone like you catches any mistakes before I make them. Specifically:
Originally Posted by chaterlea25
I would think that 0.001in. is too tight for the cam bushes, this is a total loss lubed engine you need "space" for the oil to get into the bush bores
Hmm. Your statement has implications for the timing side crankshaft bush as well.

First, for what it's worth, despite the timing side bush being 1-3/4" long the faux crankshaft I made rotates in the cases without problem so right now the alignment is pretty good. The ~0.004" clearance (0.08741"-0.8745" crank & 0.08782" bush) helps allow this, but I suspect it means the original machining of the cases is responsible for the good alignment. That, plus an aftermarket bush having reasonably concentric ID and OD, which would be expected. But, back to the clearance issue.

Reading the Ariel 'Owners Guide' is one thing, but there's no substitute for tracing the oil system myself in order to understand it. What the section 'Engine Automatic Lubrication Explained' says is "Oil is supplied by means of an internal mechanical pump... delivers it to a recess in the flywheel, from which it travels to the big end bearing via a hole drilled through the flywheel." What I now know this means is while it appears a drilling delivers pressurized oil to the timing side crankshaft bush, what actually happens is it delivers it to a groove beside the bush from where it travels to an annular volume on the face of the flywheel defined by a machined surface in contact with the face of the bush and a ring on the flywheel that overlaps a circular projection on the crankcase. Inside that annular volume is a hole drilled at an angle from which centripetal force takes the oil to the big end. After leaving the big end it joins the oil-rich smog inside the crankcase, some of which condenses and makes its way to one hole at the top of one end of the timing side bush.

The crankcase smog gets pumped into the timing case through two one-way reed valves where it condenses and fills the case to a level above another hole that leads to the timing side bush. The level of the liquid oil is maintained by a 0.08" hole back into the crankcase. Interestingly, this hole could have been drilled directly over the hole leading to the timing side bush to drip liquid onto it, but it wasn't. This liquid timing case oil also gets splashed around by the cam gear and pinion where some of it enters holes at the top of the outer camshaft bush. The inner camshaft bush has no hole over it so it relies completely on whatever oil somehow enters it via either end of the shaft (none of the shafts have scrolls on them to encourage oil flow). Because having actual liquid oil in the timing case is essential, when the case is drained every 1000 miles through a plug at the bottom, it is necessary to refill it with 1/4 pint rather than waiting for that to happen by condensation.

OK, back to clearances. None of the three bushes is pressure fed, which is the same as for the bushes in a BSA gearbox. I use that as an example because my measurements of a few layshafts on the shelf indicate that BSA made their 11/16" shafts to allow for 0.002" clearance. Given this, if you were me, would you make new camshaft bushes given their 0.003" clearance? Although the Ariel's crankshaft is larger (7/8") it appears its clearance of 0.0037-0.0041" gives me no choice, although I'll remeasure everything before replacing anything.

Originally Posted by chaterlea25
I would align the cases as best possible and then ream two of the bolt holes,
Then make dowels to suit them so reassembly accuracy can be repeated
That's not a bad idea, but there are pros and cons to it. The pro is it would make it easier for some future rebuilder to accurately assemble the cases even if they didn't realize they needed to be concerned with this. The con is it would require metal to be removed from the cases to make room for the dowels, and I try very hard not to remove metal from original pieces whenever possible. The plate I made allows me to accurately assemble the cases myself as many times as needed, and I will have it along on the Cannonball if, god forbid, the engine has to come apart at all, let alone that far apart.

Posted By: kommando

Re: 1928 Ariel Model C - 11/26/17 7:19 pm

I can understand the logic behind giving a bigger clearance when there is not much oil about in an effort to get it in there but the greater the clearance the quicker it will also exit so do not overdo it.

From

http://edge.rit.edu/edge/P14453/public/Research/2-_LEADER_-_Understanding_Journal_Bearings.pdf

6. Stay within design guidelines on clearances. General rule is 1.5 mils (0.0015 inches) per inch of shaft journal diameter. 3.0 mils/inch diameter is
excessive clearance in most cases.

Also table on page 8 for Hydrodynamic bushes

http://www.leonardocentre.co.uk/Media/Default/Documents/Book_1_bearings.pdf

which confirms the figure but relates it to speed of shaft and journal size in a more detailed manner.
Posted By: gREgg-K

Re: 1928 Ariel Model C - 11/26/17 7:26 pm

Thanks RPM, for the pointer to Ferrea. I'll give them a try.

. Gregg
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/27/17 12:50 am

Kommando, thanks for the links. Life would be simpler if I would just buy bearings and bushes on blind faith from dealers, install them, and blame myself if/when they failed after some number of miles. But, nooo, it isn't simple because I know details like 'C' clearances on bearings, properties of different bronzes, boundary layer lubrication, line boring, proper alignment of the deck, etc., etc. So, instead of blissful ignorance I have to spend hours doing research.

For those of you who are still leading a blissful life, in this post you can see with your own eyes (or, you used to, before Photobucket stepped in) a bearing that was nonfunctional, with the problem due to it having been mis-machined by ~1/64". I had ordered two and both were mis-made the same way. Despite this the supplier responded:

We sell approximately 80 each year and we are not aware of any concerns raised.

Even if a supplier stocked camshaft bushings for 1928 Ariels the only way I would know that, in turn, their suppliers had manufactured them using a proper composition of bronze (instead of one of scores of compositions that look the same but that have the wrong properties) that would last 4000 miles is if they actually lasted 4000 miles, rather than wearing out in 1000.

Moving on from bushes to bearings, relevant background information is I have found sources for unshielded RMS8 bearings made by FAG and SKF, both unmarked which means they would be of CN ("normal") clearance. As an aside, although the bearing now in my Ariel has a shield, presumably the original ones did not. Because of the design all but an annular area of width 0.028" of the oil's escape route through the bearing is blocked by the case so I have to wonder if the inner races of 1928 bearings might have been just that much wider. In any case, I'll either try to remove the shield from the current bearing and transfer it to whatever name-brand bearing I buy or, if that doesn't work, make my own shield from shim stock.

The OD of my current bearing is 2.4998" and the bore in the crankcase is slightly larger and slightly oval, with clearance varying between 0.0007" and 0.0017". The sprocket cush drive fastens securely to the bearing's inner race via a spacer and Ariel calls for an end float of 0.008-0.012". What is means is the crankshaft could/would move this bearing back and forth in the case by this amount at present. So, what to do? Three possibilities open for comment are:

-- Accurately register the case and open up the hole just enough to make it round, i.e. leaving it oversize by 0.0017" all the way around. Electroplate 0.0018" on the OD of a new bearing which would result in a 0.0019" interference fit. The risk would be a ~0.002" interference fit would make a CN bearing too tight.

-- There's room to open up the case by ~1/8"-dia. at most so a 1/16" wall thickness steel or brass sleeve tightly pressed in the case (0.0025") could be made that also allowed for a somewhat looser press fit (0.0015') for the bearing. The risks with this approach would be overdoing the sleeve press fit and cracking the case, and that a 0.0015" bearing press fit could make a CN bearing too tight.

-- Locktite 648 would be the easiest of the three possibilities. OK, OK, Loctite doesn't have the best reputation for main bearings, but Ariel didn't deign to include any kind of mechanical retention system so they expected (hoped for, crossed their fingers that,...) a press fit would suffice. According to tables and a formula in 'Machinery's Handbook' it takes 1.1 ton for a 0.002 interference fit of 2.5"-dia. steel in cast iron, so the force would be less in Al. If you study the Loctite 458 data sheet you'll see that fully cured on properly prepared Al the sheer strength is 2900 psi which, for the surface area of the bearing, means it would take 8.5 tons to move it.



Posted By: kommando

Re: 1928 Ariel Model C - 11/27/17 9:19 am

Loctite is definitely an issue when used to locate steel ball bearings in an alloy case, tried it twice and it took less than 1000 miles both times before failing, my theory is that the differential expansion rates aluminium to steel break the bond. If my theory is correct then it will not fail in the same way on a steel ball bearing in a cast iron case, but as it's only a theory then you best stick with either a sleeve or electroplate the bearing. Both are tried and tested leaving you only with the CN C3 decision, there is an overlap between the 2 tolerances.
Posted By: Shane in Oz

Re: 1928 Ariel Model C - 11/27/17 11:29 am

It looks like Loctite Bearing Lock is out.

Rather than plating the outer race or boring and sleeving the crankcase, would it be practical to use a metric bearing with a 64mm o.d.?
For example, the AB44203S01 is 26 x 64 x 16 and 28BC06S10 is 28 x 64 x 15. It's generally preferable to sleeve a steel shaft than an alloy housing. Those particular bearing are 3mm and 4mm narrower, which would have an effect on load rating, but may possibly allow room to machine a circlip groove if one wishes hard enough.
Posted By: gavin eisler

Re: 1928 Ariel Model C - 11/27/17 2:33 pm

I tried to take up play on my A65 which had an oval mainshaft, play between DS main and bearing inner, used bearing fit loctite,didnt work.
I did successfully repair a cracked marine engine, the main bearing housing had cracked, the iron cases were welded up then the bearing housing enlarged to take a top hat sleeve, then bored this sleeve to suit, there was a lot of meat to play with and it worked out well. The top hat sleeve was secured by c/ sunk screws around the flange. A bit like some Norton motors i have seen. Although with only a 1/16th to play with , hmmm.
Plating or grinding down an OS bearing seems like a better fix.
Posted By: RPM

Re: 1928 Ariel Model C - 11/27/17 3:13 pm

I have never had any luck with the loctite bearing fit into alloy cases either.

My mentor and friend Ed Mabry ( builder of the first sit on and ride 250 mph motorcycle and SEMA member No. 12) had a sign on his shop wall that stated.

" To much knowledge can often be a limiting factor"

We could also quote the great EJ Potter aka The Michigan Madman

" Ignorance can be a powerful tool when applied at the right time. Often and usually surpassing knowledge."


Just messing with MM. I think your approach is well worth it and I have learned a few things reading this post.


Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/27/17 3:52 pm

Originally Posted by kommando
Loctite is definitely an issue when used to locate steel ball bearings in an alloy case, tried it twice and it took less than 1000 miles both times before failing
Before pounding a stake through the heart of this possibility, did you note which of the many Loctites you used? Also, did you use an activator and, if so, which one?

Originally Posted by Shane in Oz
Rather than plating the outer race or boring and sleeving the crankcase, would it be practical to use a metric bearing with a 64mm o.d.?
Hmm, I hadn't thought of that. Thanks for raising the possibility. Even though the extra 0.197" diameter of either of those bearings is too much to accommodate by enlarging the cavity your suggestion will send me to my shelf of bearing books to look for alternatives.

Originally Posted by gavin eisler
Plating or grinding down an OS bearing seems like a better fix.
I'll add grinding the OD of a 64 mm race down to 63.6 (2.5039") to the list of possibilities.

As I mentioned in my previous post, the fact the ID of the sprocket side of the cavity almost shields the bearing made me think the original bearing Ariel used might have had different specs. Now add to this the fact the current RMS8 is 3/4" wide but the cavity is a devilish 0.666" deep so the bearing sits proud by 0.084". Instead, if the original bearing had been 5/8" wide it would be recessed by 0.041 (although, not enough for a circlip, I'm afraid). That difference easily could have been accommodated by a 1/8" spacer on the crankshaft. Unfortunately, even if I could find such a bearing it doesn't help me with the retention problem.(*)

Originally Posted by kommando
electroplate the bearing. ...tried and tested leaving you only with the CN C3 decision, there is an overlap between the 2 tolerances.
Even if Locktite would work, and even though it would be easier if it did, more often than not metal provides permanent solutions to problems while glue does not. So, after locating whatever bearing I will end up using, it looks like it will be time to mask the internals and fire up the electroplater.

All of the 'C' grades overlap with each other, e.g. a loose C(i) is tighter than a tight C(i+1). I don't have a choice of grades in the case of the two name-brand RMS8s that I've found but perhaps I will if a mythical 5/8"-wide version turns out to be real. And available.

As an aside, it's possible to measure the actual clearance of a given bearing. According to one table a force of 49 N (11 lbs.) on the outer race of a 2.5" OD bearing rated CN will displace it sideways with respect to the inner race by 5 micrometers (197 microinches). The smallest divisions on the most sensitive mechanical dial indicator I have, a Mahr Supramess, are 0.5 micrometers (as an aside to this aside, it's (barely) possible to control the position of the needle with a finger to ~1 division on this mechanical device, i.e. to the wavelength of blue/green light).

It would be easy to make a base to which the inner race could be rigidly clamped and the outer race would be free to be pushed back and forth against the tip of the indicator. Making such a test rig has been on my to-do list for a few years, ever since I came into a small collection of used Gold Star engine ball and roller bearings. All of them "feel" good, but a simple test rig would allow me to determine their actual clearances.

RPM: I've certainly seen plenty of examples over the years of ignorance being bliss. Unfortunately, I was born cursed with a thirst for knowledge that has haunted me my entire life. Luckily, although curiosity killed the cat, I'm still alive despite several close calls when I was young.


(*) Series RLM bearings are narrower. In particular, RLM9 is 5/8" wide. The SKF catalog rates it for a dynamic load of 3350 lbs. whereas the wider RMS8 is only ~7% higher at 3600 lbs. Update: The RLM9 is for a 1-1/8" shaft, but adding a sleeve to the crankshaft wouldn't be a problem. The RLM8 is for a 1" shaft but its OD is 2-1/4" so it would require a sleeve for the case, which would be more work. If not for the crankpin nut, with the narrower 5/8" bearing it would have been possible to bolt it place.
Posted By: chaterlea25

Re: 1928 Ariel Model C - 11/27/17 7:42 pm

Hi MM, and All
Going back to my earlier observations on cam bush clearance, 0.0015 - 0.002 in. would be my aim
Finding 0.003 is an acceptable value on an old engine, and at 0.004 I would advise replacing
That said,If you read the workshop manual for Indian Chief engines they do not advocate changing bushes till 2 x the above value

As to the main bearing issue, I believe the problem was caused by the crank running out of line ?
A further bearing to consider is a 6305 (25x62x17) modified with an imperial 1" bore ? ( I think that they might be available to order?)
Ok so you would need to remove less from the casing to fit the sleeve, but going that far would it be easier to repair for the original size bearing
I would opt for using the original size bearing if possible as the casing housing is somewhat oval then it will need "repair" anyway
I would opt for the 0.002 interference fit and a C3 bearing


The big end lubrication system from your description sounds just like the JAP engines of the period (same designer I believe ?)
The system relies on the crankcase being airtight to raise a vacuum inside the cases as the piston rises, the breather valves allow pressure to escape into the timing case as the piston descends
To work properly the timing side bearing needs to be shielded to prevent air being drawn in
So either the mainshaft / sleeve needs to be a tightish fit where the shaft comes through the case or fit a bearing with Z or RS on the inside
(similar to what some people do with Gold Star engines)
Cases are often worn due to running with worn main bearings in the past

John








Posted By: kommando

Re: 1928 Ariel Model C - 11/27/17 8:22 pm

It was in a silvery grey tube just called 'bearing fit' but no number, nearest current equivalent is Locitite 660, I did not use an activator. I assumed after the first failure it was my process that was at fault, so second time I was much more meticulous, both times I used acetone to clean all surfaces and allowed the product to set at room temp over first time 1 day and 2 days the second. Both times when it failed the bearing was loose in the housing and sections of the loctite were in the sump.

Tech sheet for 660

https://www.bearingboys.co.uk/uploads/660-EN.pdf
Posted By: KevinN

Re: 1928 Ariel Model C - 11/28/17 10:51 am

Charles,

All this talk about clearances reminded me that Nicholson's book had an Ariel section in it. Unfortunately the cam bushing is not listed in the clearance table. I thought I'd post the table and a few other things anyway, in case they are useful. This is from a 1965 edition, so I'm not sure how applicable it is to your machine.

[Linked Image]

[Linked Image]

[Linked Image]

[Linked Image]




Kevin


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/28/17 8:14 pm

Originally Posted by kommando
It was in a silvery grey tube just called 'bearing fit' but no number,
Thanks for this. As you know Loctite comes in at least 127 variations, but all are subject to the same differential expansion issue you mentioned in a previous email.

Originally Posted by KevinN
All this talk about clearances reminded me that Nicholson's book had an Ariel section in it.
Kevin, thanks for posting that. I'm looking for as much technical information as I can find on this machine. I actually have a full set of editions going back to Nicholson's 1st, which I looked through when compiling my 'shop manual'. Unfortunately, even though my Ariel was only 20 years old then, nothing in Nicholson is directly related to it.

Originally Posted by chaterlea25
The big end lubrication system from your description sounds just like the JAP engines of the period (same designer I believe ?)
The system relies on the crankcase being airtight ...
Yes, Val Page came to Ariel after designing JAP engines. The crankcase isn't quite sealed because there's a pipe about 3" above the bottom that takes oil mist into the primary case where it condenses and drips on the chain. However, a rough measurement shows the total area of the breather holes into the timing chest is ~7x that of the breather pipe so only a fraction of the oil mist ends up on the chain. The timing chest also has an outlet pipe for excess oil, taking it to the drive chain.

Originally Posted by chaterlea25
As to the main bearing issue, I believe the problem was caused by the crank running out of line ?
I would opt for using the original size bearing if possible as the casing housing is somewhat oval then it will need "repair" anyway
I would opt for the 0.002 interference fit and a C3 bearing
The big 'if' is if I can find an appropriate C3 bearing. I've posted a question about this on the Ariel Owner's Club website in the hopes some there has useful experience on bearing choices to offer.

The high spots in the housing and the surface of the bearing have been polished by movement of the bearing. This could have happened when the previous rebuilder pressed the bearing into a too-large oval housing or, more likely, the polishing marks and ovalness are due to the bearing having "walked" because the previous rebuilder assembled the crankshaft with the shafts not accurate aligned. Either way, and not for the first or last time, I'll say that I'm glad I'm completely rebuilding this already-"rebuilt" bike.

My measurements showed that to make the hole for the bearing round again requires removing ~0.001" from the diameter. However, to do this requires mounting the mating face of that half of the crankcase precisely parallel with the mill bed in order to make that hole precisely perpendicular. As chaterlea25 knows, machining anything is 90% fixturing and 50% everything else, and repairing the crankcase is an example of that.

The case has 8 machined "ears" on the outside for clamping the halves together and for mounting the engine in the frame. I set the case on two 1/4"-wide parallels on the surface plate that spanned two of the mounting lugs on opposite sides. Since the machined surfaces on the case aren't perfectly smooth I set another parallel on top to average out the roughness and then used a test indicator to run across the top of it. Working my way around the entire case two lugs at a time the maximum tilt was ~0.005". This is great because it means I will be able to mount the case to the mill using those lugs, with shim stock to make final tweaks. I then will find the approximate center of the ovaled hole that will requires the least amount of material to be removed to make it round again.

The actual machining of the hole will take about a minute, but only after at least a half day setting everything up. Toward that end, yesterday I machined two standoffs for holding the case on the mill bed, consisting of 1-1/2"x1-1/2"x4-1/2" blocks with 3/8" through holes to bolt to the table, and 3/8-16 tapped holes for bolting the case to the blocks. When I'm ready to do the machining, shims between the blocks and case will adjust the mating surface to be flat.

1960s catalogs from Hoffmann, SKF, R&M, and FAG all have "single row deep groove ball bearings" of the size of the RMS8 that was in the engine. What's interesting is the wide range of capacities shown for these bearings, all of which would be identical in actual performance:

R&M: 'Basic Capacity' 460 lbs at 4000 rpm
Hoffmann: 'Safe Working Load' 1300 lbs at 4000 rpm
SKF: 'Basic Capacity' static 2200 lbs., dynamic 3250 lbs., Max. rpm 13,000
FAG: 'Load Rating' static 4000 lbs, dynamic 3800

A delayed delivery of bearings needed to mount the crank on my rollers is now scheduled for today. As soon as those bearings actually show up I'll be able to make accurate measurements of the current state of the crankshaft. The big end nuts have socket head cap screws retaining them so it has been rebuilt after leaving the factory.


Attached picture IMG_6228.JPG
Posted By: gavin eisler

Re: 1928 Ariel Model C - 11/28/17 8:31 pm

Hi MM,
The National Motorcycle Museum in the UK has BMS copies of Ariel period data here.
http://www.nationalmotorcyclemuseum...ith-bms-motorcycle-manuals/ariel/page/2/
Maybe you have these already?
Posted By: L.A.kevin

Re: 1928 Ariel Model C - 11/28/17 9:52 pm

MM, I've only recently stumbled on this thread, and though I can't add much to it, I must say this is a really great read. Thanks, and I hope to get some time to be there at the finish to cheer you on your Ariel and my good buddy Richard on his Norton.

Kevin
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/29/17 3:19 am

Originally Posted by gavin eisler
Maybe you have these already?
Thanks very much for the link, but paper copies of the factory literature came with the bike. Also, the Ariel Owner's Club has pdfs of several 'how-to' magazine articles from the time.

Originally Posted by L.A.kevin
I hope to get some time to be there at the finish to cheer you on your Ariel and my good buddy Richard on his Norton.
I hope to see you there on your to-be-rebuilt Gold Star.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/29/17 4:03 pm

I've now had it confirmed by someone in the AOMCC that, although no details are in the '28 Ariel catalog, the '27 and '31 catalogs list an MJ1 as the drive-side bearing. I hadn't thought to look in my own copy of the '27 catalog (note to Gavin -- it's a BMS photocopy that came with the bike along with other literature), but indeed it does list an 'M.J.1 Ball Bearing' at a price of 12s 0d.

Now on order is an RHP (successor company to R&M, formed in '69) MJ1 bearing, sealed but of unknown clearance. I'll have to wait until it shows up to see what clearance is stamped on it, but I'd bet it will be a CN. As mentioned in an earlier post, there is an overlap of clearance grades so I'll make a jig to measure the actual clearance then plate its OD for a ~0.0015-0.002" press fit (depending on the measured bearing clearance) in the waiting-to-be-repaired crankcase hole.

The gearbox sprocket with hub I ordered long, long ago finally was delivered by UPS yesterday after its tour of the country, but the bearings I need to balance the crank have been delayed until tomorrow. It's a good thing I'm able to work on things in parallel because linearly, this would take forever. Still, every item that (eventually) arrives brings me a step closer to the finish.
Posted By: gunner

Re: 1928 Ariel Model C - 11/29/17 7:45 pm

Don't know if this helps, but Googling MJ1 bearing with C3 clearance shows that an RHP version is available in the UK, see This Link.

This bearing has no seals (presumably as per original?) and measures 25.40x63.50x19.05 (1x2-1/2x3/4).

I'm no machinist but I would imagine your approach of very accurate measuring, milling out any ovality, re sleeving and ensuring alignment between timing and drive side bearings is likely the best approach for future reliability.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 11/30/17 3:45 am

Originally Posted by gunner
Don't know if this helps, but Googling MJ1 bearing with C3 clearance shows that an RHP version is available in the UK, see...
It helps a lot. Thanks very much. It also helped me send another ~$67 of my money to ease the Brexit debt to the EU. If the bearing I ordered earlier today turns out to be a C3 as well I will have wasted this money but, if not, I'll have a necessary backup option if the other one turns out to be too tight.

To prepare the case for the bearing I mounted it to the mill's table using the fixtures I made on Monday. However, prior to doing anything to the case I ground and honed a HSS bit and tested it on the ID of a scrap piece of 3" Al tubing to make sure it cut smoothly. I then moved the case under the spindle and trammed the mounting flange. I was pleasantly surprised to find it perpendicular to the spindle to 0.0005" across the 9" diameter so no shimming was needed. I then centered the hole by tramming near the outer edge, center, and inner edge of the hole with a 0.0001" indicator. Perhaps unsurprisingly, the hole was pretty cylindrical (to +/-~0.0002") around 2/3 of the circumference but distorted downward by ~0.0015" max. on the other 1/3. This is what would be expected if a rigid cylinder (the crank) had hammered downward on the bearing for a long time. By the way, working to a ten-thou. takes a lot of effort.

I then swapped the indicator for a boring bar and sneaked up on the final dia. a few ten-thou. at a time, so it's now ready for the bearings. The bearings, on the other hand, will need some plating before they're ready for the case.

Meanwhile, the bearings needed for holding the crank in the balancing wheels arrived. I reserve the right to change the figures when I have time to make a more careful measurement and a minor correction for the weight of the socket head screws pinning the main bearing nuts, but I don't expect much change. Anyway, using the weight of the original Australian/Canadian piston the balance factor when it left the factory was 58% (+/-~1%). The piston that was in the bike when I got it changed this to 61%.



Attached picture IMG_6241.JPG
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Posted By: gavin eisler

Re: 1928 Ariel Model C - 11/30/17 6:32 pm

Originally Posted by robcurrie
60% ....my highest math score

Rob C


Well done Rob, on the BF contest , though MM himself quoted 58% for the early goldies.
Posted By: robcurrie

Re: 1928 Ariel Model C - 11/30/17 7:17 pm

Thanks Gavin, you must have a good memory - that was months ago.
Posted By: old mule

Re: 1928 Ariel Model C - 12/02/17 4:37 pm

Regarding Chaterlea's dowel suggestion, plenty of crankcases (and other machinery) use hollow dowels to locate things, with a through bolt to fasten them.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/03/17 7:10 pm

Originally Posted by old mule
plenty of crankcases (and other machinery) use hollow dowels to locate things,
Yes, that would be a more elegant solution than my flat plate, but it would take a fair amount of time to make jigs to align the cases to bore the holes for the dowels. The flat plate I made for the top accomplishes accurate alignment without me spending a lot of additional time.

The Alpha crankpin has cleared Customs at JFK and is now slowly making its way across the U.S. The bearing from the U.S. supplier arrived yesterday and the other one from the UK should be in transit, as should a Cu plating kit. My first thought was to assemble the electroplating chemicals myself, but not all chemical supply houses will sell to individuals, and others require filling out registration forms, so I decided to take the easy way out and just buy a kit. I'll post details of the Cu plating process after I'm happy with the results.

While I await the arrival of these items I'll turn to other things so there will be a temporary pause in the rebuild.
Posted By: koan58

Re: 1928 Ariel Model C - 12/03/17 9:34 pm

A fascinating log! I look forward to hearing about the electroplating, I've heard it recommended many times, but never tried it. I'm sure that you will do it with your usual scientific approach! Good luck.
Posted By: JubeePrince

Re: 1928 Ariel Model C - 12/05/17 3:14 am

Originally Posted by KevinN

I would like to add one statistic to your list; there are four riders from the state of Nebraska. In fact, we all live within about a 20 mile radius!


Must be something in the water there, then?! laugh

MM - Been a few weeks since I checked in here. Made a 3+ hour plane ride much easier....looking forward to the route details being published. Be nice to get a few of us bb.com'ers from the mid-Atlantic area to cheer you on.

Cheers,

Steve
Posted By: George Kaplan

Re: 1928 Ariel Model C - 12/05/17 12:39 pm

Originally Posted by JubeePrince

Must be something in the water there, then?! laugh
Steve


What the hell do they put in the water in California then? There are 19 from California.

(also 10 from Texas)

John
Posted By: KevinN

Re: 1928 Ariel Model C - 12/05/17 3:37 pm

Originally Posted by George Kaplan
Originally Posted by JubeePrince

Must be something in the water there, then?! laugh
Steve


What the hell do they put in the water in California then? There are 19 from California.

(also 10 from Texas)

John


I was just showing some pride in my little state. I didn't mean to take anything away from anyone else. California has 20 times the population of Nebraska. Just the city of Los Angeles has more than twice as many people people as the entire state of Nebraska. To think that almost 4% of next years cannonballers live in a 20 mile circle that contains only a couple of thousand people seems noteworthy to me. It's not the water, it's that we grow up fixing stuff. You know, so we can grow your food.




Kevin


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Posted By: George Kaplan

Re: 1928 Ariel Model C - 12/05/17 5:53 pm

Kevin, my apologies, I didn't appreciate the fact that Nebraska was punching so far above its weight when you took a states population into account.

John
Posted By: JubeePrince

Re: 1928 Ariel Model C - 12/06/17 2:30 am

Originally Posted by KevinN
It's not the water, it's that we grow up fixing stuff.


Hi Kevin,

My tongue-in-cheek water comment aside, I can identify with the sentiment. Having grown up in the northern reaches of New England, we did the same. Yankee ingenuity! A way of life that seems to be slowly dying out, unfortunately.

Cheers,

Steve
Posted By: KevinN

Re: 1928 Ariel Model C - 12/06/17 7:59 pm

No need to apologize guys. Trust me, I'm not going to melt! I appreciate your interest in the event, and I'm enjoying the discussion and the build.




Kevin


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Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/10/17 9:00 am

Originally Posted by Magnetoman
While I await the arrival of these items I'll turn to other things so there will be a temporary pause in the rebuild.
Originally Posted by KevinN
I'm enjoying the discussion and the build.
Thanks to everyone who's been following along. I've been occupied with other things the past week but expect to be back to the build within the next couple of days.

Originally Posted by JubeePrince
Be nice to get a few of us bb.com'ers from the mid-Atlantic area to cheer you on.
You're more than welcome to organize something. But, it starts in Maine so wouldn't that count as the North-Atlantic? Perhaps you could organize NATO to cheer us on at the starting line...


Posted By: Alan_nc

Re: 1928 Ariel Model C - 12/10/17 9:54 am

Do you know how far South you will go before heading West?
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/10/17 10:29 am

Originally Posted by Alan_nc
Do you know how far South you will go before heading West?
All we know for now are the locations of the start and finish and the 'day of rest' (Sturgis SD), plus the total mileage (which I don't remember, but a bit less than 4000). Google maps with those three fixed points, with the 'avoid highways' box ticked, and forcing the route to avoid hostile foreign territory (i.e. Canada), gives the shortest total route as 3285 miles. If I force the route to go through Cincinnati it increases to 3474 miles, which means there's certainly the possibility for the route to go pretty far south both before and after Sturgis.

Anything beyond the above speculation is just, um, speculation.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/13/17 3:56 pm

I returned yesterday from a trip to find one of the two drive-side bearings I ordered had arrived (with CN and C3 clearances), along with the Cu plating kit and the crankpin. The latter gave me a bit of a worry when I unpacked it because it was labeled for 250 and 350 Ariels. However, checking Alpha's site shows that indeed the same crankpin is also listed for my 500 Black Ariel. Later in the day the postman delivered the C3 clearance bearing from England, and I already had the necessary bronze for making the various bushes, so I now have what I need -- or, what I presently know I need -- for completely rebuilding the bottom end of the engine.

Time in the air gave me the opportunity to do all the calculations needed to determine the original balance factor used by the factory. However, I want to double-check the measurements and calculations before posting them. First, though, I have to recover a bit from jet lag before pulling the slide rule out to check the figures. Also, electroplating is a precise process where knowing the current, valence, and material density allows determining and controlling the thickness by calculating the time required. Again, though, this is a calculation best done with a fog-free mind to avoid making mistakes of factors of 60 for min. vs. hrs. or whatever.

Meanwhile, while I was away the riders were sent a top-secret email giving the daily stops along the Cannonball route, but asked not to share the information. However, I don't think it's violating the organizer's request for secrecy to note the route will skirt the lower edge of the Great Lakes rather than have us ride over or under the water.


Attached picture IMG_6344.JPG
Posted By: old mule

Re: 1928 Ariel Model C - 12/13/17 10:36 pm

Accurate Bearing in Addison IL has a very good reputation for finding and supplying obscure and "obsolete" bearings, I have used them for industrial machinery bearings cataloged in 1924. And good personal service too.
Also, did I somewhere read that later Ariel scramblers were often fitted by competitors with Triumph 2 valve oil pumps?

I like hearing your descriptions of machining and mensuration- best motorbike episode on the net, now, I say.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/14/17 1:58 am

Originally Posted by old mule
I like hearing your descriptions of machining and mensuration..
Thanks for your nice words.

As a mensuration musing, for reasons I'll explain later (if I remember...) it appears the flywheels were balanced individually and then the complete crankshaft tweaked to the final balance factor after assembly. Or, quite possibly, the entire balancing operation was done on the individual flywheels and no further machining done on the crankshaft after it was assembled.

Roughly speaking, my flywheels consist of relatively thin (0.6") disks 5½" in diameter with thicker (1.2") rims extending from there to the 8" outer diameter. The castings actually are more complicated than this, but these dimensions will serve for present purposes.

The moment of inertia of a disk scales as the square of the radius so the outer rim contributes significantly more than the inner part. The 1.2"-thick outer rim of each flywheel weighs

~ π/4 x 1.2" x (8"2 - 5½"2) x 0.284 = ~9.0 lbs

where 0.284 is the density of iron in lbs./cu.in. (nb. the total crankshaft assembly weighs 24.0 lbs.)

On the outer surfaces of both rims, on the crankpin/shaft axis, are drilled two 5/16" balancing holes. Since these holes are roughly the same depth on both rims the following applies to each of them. In one rim the sum of the depths of these holes is ~0.27", so the weight removed from that rim by these two holes was ~ π/4 x 0.27" x (5/16"2) x 0.284 = ~0.021 lbs. (9.5 grams).

The above shows that to do the final balancing required removing just ~0.021/9 = 0.25% of the "effective" mass of each flywheel. However, rather than drilling those holes after assembly, each flywheel could have been separately balanced using an appropriate weight in the crankpin hole in order to result in the final desired balance factor for the total crankshaft assembly.


addendum:
Originally Posted by old mule
- best motorbike episode on the net, now, I say.
I meant to include the following yesterday. If you haven't already found it you should check out KevinN's Indian build on the AMCA Forum. I know, it's not British, but it's not like there's a fundamental difference in the technology. It starts with his acquisition of the bike four years ago, through to his no-points-lost run in the last Cannonball, and recently has started up again with his rebuild in preparation for the upcoming one. His design and fabrication of new timing components is fascinating.

Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/14/17 11:07 pm

I bolted the drive-side bearings to the bed of the mill using a washer as a spacer to hold the inner races off the bed, and used a 1-micron Mahr Supramess indicator to measure how far I could displace the outer races with the uncalibrated force of my hands (which was less than the 11 lbs. called for).

Used no-name ~5 microns (this is the bearing that was in the bike)
New RHP CN clearance ~10 microns (~0.0004")
New RHP C3 clearance ~20 microns (~0.0008")

Referring to the instructions by BSA and Triumph that bearings should drop out of cases when heated to 100 oC, the differential thermal expansion between steel and Al means the proper interference fit is ~0.002" at room temperature. Bearings should have essentially no clearance between the races and balls in operation. The fact that the clearance of C3 bearings closes up to the proper running clearance of ~0" when installed in Al cases with a 0.002" interference fit means the compression of the outer race by the Al closes up the clearance by ~0.001". As my measurements above show, the no-name bearing would be much too tight, the CN bearing would be somewhat too tight, but the Goldilocks C3 bearing should be perfect.


Posted By: JubeePrince

Re: 1928 Ariel Model C - 12/14/17 11:25 pm

Originally Posted by Magnetoman
You're more than welcome to organize something. But, it starts in Maine so wouldn't that count as the North-Atlantic? Perhaps you could organize NATO to cheer us on at the starting line...


Yeah, Maine is definitely 'down-east' (at least that's how we referred to it when I was a lad in VT). Unless the route is planning on hugging the US/Canadian border, perhaps a dip into PA or OH at the very least. That would be doable from the mid-Atlantic. Fingers crossed!

Cheers,

Steve
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/15/17 5:09 pm

Originally Posted by JubeePrince
Unless the route is planning on hugging the US/Canadian border,
Without giving anything away about the precise route, it only could hug the border if there were snorkels for the bikes and riders and I don't see them on the list of required or optional items...

Today's expensive development is the result of the Dec. issue of the Ariel club's newsletter arriving yesterday. In it is an ad for "high ratio" gearsets that the club commissioned for Q-type gearboxes. The ad claims the high ratio gearbox "makes for greater riding pleasure -- especially for the overhead valve models." Hmm, I like riding pleasure, and I have an ohv model...

Burman supplied their 3-speed Q gearboxes to Ariel for 4-5 years with "low standard," "high standard," and close-ratio "T.T.A." gearsets. Mine is a QL (i.e. low) with spread in ratios between bottom and top of 2.789. This is somewhat wider than the 2.580 spread of the (4-speed) BSA STD box, resulting in a large jump between 2nd and top.

The QH (high) gearbox has a smaller, 2.018, difference in gearing between bottom and top, falling halfway between the 1.754 of the (infamous) Gold Star RRT2 and the 2.343 of the SCT. The former is quite a problem around town because it requires a lot of clutch slipping to get moving when the overall gearing is set for the highway (albeit, set for a bit higher top speed than the Ariel), while the latter is quite nice around town as well as on the highway. So, I queried people on the Ariel club website to find if the QH's spread of ratios meant in practice it behaved more like the RRT2 or like the SCT.

The answers convinced me that the QH is a better choice for the Cannonball because of the big jump between 2nd and 3rd on the QL. This would be especially problematic in hilly or mountainous country. The QH will make the gearing tall in 1st, but it seems like it won't be so tall that it would be a problem. So, another £400 (plus shipping) of my money will be going toward helping ease the pain of Brexit.

Posted By: kommando

Re: 1928 Ariel Model C - 12/15/17 5:30 pm

The Balance of payments problem looks to be solved by MM's Cannonball Run. Can you enter for 2019 as well, on a different bike of course, to make sure its solved for 2 years running.
Posted By: edunham

Re: 1928 Ariel Model C - 12/15/17 7:35 pm

It sounds like it will be just thing for commuting when the Cannonball is over. You just need to figure out how to bolt a yellow milk crate to the back!

Ed from NJ
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/15/17 8:07 pm

Originally Posted by kommando
The Balance of payments problem looks to be solved by MM's Cannonball Run. Can you enter for 2019 as well, on a different bike of course,
Greece has much more severe economic problems than the UK so I looked into restoring a classic Icarus. Unfortunately, it is well documented to have a fatal overheating problem, especially on sunny days.
Posted By: Tridentman

Re: 1928 Ariel Model C - 12/15/17 8:46 pm

Pity that--it would have made a Crete bike!
Incidentally--why the secrecy on the part of the organizers ref the route?
Posted By: kevin roberts

Re: 1928 Ariel Model C - 12/15/17 9:17 pm

i actually started to look up icarus motorcycles, then said, wait a minute . . .
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/15/17 9:30 pm

Restoration of the Icarus would have made for a story of mythological proportions if hopes for it hadn't been drowned.

I can only guess that the organizers might not as yet have locked in all the resort hotels and spas for us to stay in along the way so they want to keep the route, i.e. the daily stops, secret until they do. But, that's just a guess based on no information whatever.
Posted By: gREgg-K

Re: 1928 Ariel Model C - 12/16/17 12:28 am

Originally Posted by Magnetoman
Restoration of the Icarus would have made for a story of mythological proportions if hopes for it hadn't been drowned.<SNIP>
.

Ah, waxing poetic ... if it doesn't work, you can always wing it ...

.. Gregg
Posted By: gavin eisler

Re: 1928 Ariel Model C - 12/16/17 1:09 am

Read through the link to the Indian rebuild and run, Wow!, great stuff thanks for posting , you have got a better start , what a weird cam follower system that Indian had?3.5:1 CR and valves only 1/2 open, nice clutch though. The Ariel looks a far more modern machine in comparison. hats off to kevin for bringing back that power plus, it was pretty wrecked.
Keep on . One job at a time ( several in parallel). Interesting that he used the alloy pistons and ended up with a high balance factor, ran with it , only vibration induced failures seemed to be the exhaust manifold split
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/16/17 1:09 am

Originally Posted by gREgg-K
, you can always wing it ...
Although some entrants in past events seem to have attempted it on a wing and a prayer, I'm hoping a more grounded approach will keep me from being burned.

I've already heard back from the guy in the UK who is handling sales of the gearbox internals to confirm whether I want the "early" (no speedometer drive) or "late" (speedometer drive) set. Mine is the early type. Since this is a new item I can only hope there are no, ahem, teething problems with the gears. I hope to have the bike finished in plenty of time for tests, but even if it seems to work great I'll have the current set with me on the Cannonball as backup.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/17/17 6:44 pm

I posted the following to the Ariel Owners Club, where there are a few more Black Ariel owners than here. Not a lot, mind you, but more than here. For completeness I'm posting it here as well since some of you may find the general procedure I used, if not the actual results, of interest.

As a reminder I wanted to determine the original balance factor used by the factory on my 1928 Ariel Model C so that I could rebalance the engine for one of the two new, +60 aftermarket pistons I've already purchased. My Ariel came with a worn +30 piston and with the small end rebushed to accept the 13/16" gudgeon pin of this newer-style piston rather than the 1" originally used. So, in addition to determining weights I had to correct for the weights of different bushes as well as for the socket head cap screws now locking the big end nuts in place. However, other than socket head cap screws used to lock the crankpin nuts, and the possible exception of four 5/16" holes discussed below, there are no other signs that the flywheels have been altered by additional drilling or plugging since they left the factory.

Since a search of the AOMCC web site shows the subject of balance factors has come up more than once, along with speculation on what value Ariel might have used, below I describe in some detail the measurements, uncertainties, calculations and assumptions leading to my determination so that others can decide for themselves if they want to accept the value I found. For those who don't want to read all of this, the executive summary is that the original balance factor used in my engine was either 56% or 60% (both +/-1%) depending on an assumption about four holes described below.

A seldom discussed but fundamental issue with the static balance method as usually described is it relies on the center of mass of the flywheels being on the axis defined by the crankpin and crankshaft. If an inhomogeneity in the flywheels places the center of mass off that axis then adding weight to the hanging connecting rod (which in effect places that weight at the center of the crankpin) will draw the center of mass close to the crankshaft axis but can never precisely balance the flywheels. To achieve perfect static balance requires applying weight to the connecting rod to draw the center of mass to its point of closest approach to the axis of the crankshaft, then adding (or subtracting) additional weight from the flywheels at 90-deg. from the crank-crankpin axis.

In all there are five 1/2"-dia. balancing holes drilled on the inside rims of the two flywheels. Because of the inaccessible location of these holes I speculate that the flywheels were balanced individually prior to being assembled into a complete crankshaft. There also are four 5/16"-dia. balancing holes drilled on the outside faces of the rims. There is no way to know if these were done by the factory at the time to tweak the crankshaft into the final balance factor after assembly, or if they were done during a later rebuild to keep the same balance factor for a heavier piston, or to change it to a higher balance factor. I address the quantitative effect of these possibilities on the calculated balance factor below.

In what follows I keep the precision of individual measurements (e.g. the 10 mg of one scale) although the final quoted uncertainty largely depends on the least sensitive measurement used in the calculation. I used the following tools:

200 g balance calibrated with weights accurate to 0.3 mg. Balance reads to +/-10 mg.
6 kg balance calibrated with weights accurate to 0.1 g. Balance reads to +/-0.5 g.
6-piece set of 5-50 g balance weights each accurate to 0.01 g.
Crown-brand balancing wheels of sensitivity 1 g-cm, equivalent to 0.2 g imbalance at the radius of the crankpin.
Digital calipers.

The four "external" 5/16" holes are at the crankpin end of the crankpin/crankshaft axis and have a total depth of 3.86" resulting in a volume of steel removed of 0.296 in.3. Using 0.29 lbs./in.3 for the density of steel, the total weight removed from these four holes was 0.086 lbs. (38.9 grams)

A formula for calculating the Balance Factor can be written in the form:

Balance Factor = (balance weight + small end weight) / (piston weight + small end weight)

As can be seen, to solve this requires determining three weights as well as having a fixture for holding the crankshaft so it can rotate freely when the balance weights are added.

Small end weight:
With the bushing to reduce it for a smaller gudgeon pin it weighs 267.5 +/-1 g. However, from this subtract 7.4 g for the "excess" weight of the bronze (see 'sidebar' below for details) so it originally would have weighed 260.0 +/-2 g.
-- Current small end weight = 267.5 +/-1 g
-- Original small end weight = 260.0 +/-1 g

Piston weight:
The "piston weight" is that of the complete assembly of piston, gudgeon pin, circlips and rings. Although it doesn't enter into the calculations shown here I'll note that the weight of the additional Al used in a, say, +30 piston is not negligible. It can be calculated from the annular volume of a piston of stock diameter and one 0.03" larger than that.

-- weight of +30 piston assembly that was currently in my bike 467.5 +/-0.5g

I was lucky to find two people with original piston assemblies for the Ariel. The one in Australia is used and weighs 507.2 g and the one in Canada is new and weighs 503.5 g.

-- weight of original piston assembly weight (average of above) = 505 +/-2 g
-- weight of aftermarket +60 Gandini piston assembly 516.5 +/-0.5 g
-- weight of aftermarket +60 Omega piston assembly 435.0 +/-0.5 g


Balance weight:
I hung balance weights and washers from a wire attached to the small end until the crankshaft was in balance and weighed the final total mass. It took 196.59 g plus 10 g on the rim at 90o. Taking into account the off-axis imbalance I estimate the uncertainty in balancing the crank using only weights hanging from the connecting rod and none at 90o is +/-3 g.

The weight of the heads of the two 1/4" cap screws pinning the big end is 2 x 2.74 grams = 5.48 g. Without the cap screws it would have required that much additional weight to balance the crank originally, offset somewhat by the 7.4 g "excess" of the current bronze reducing bushing, i.e. 196.6 + 5.5 - 7.4 = 194.7 grams.

-- weight to originally balance crankshaft = 195 +/-3 g

If the 5/16" holes were added sometime later the original weight required to balance it would have been 38.9 grams less.

-- weight to balance crankshaft without the four 5/16" holes =165 +/-3 g
-- total weight to balance crankshaft in its current form = 196.6 +/-0.1 g

Original factory balance factor:

If the crankshaft in its current form (less the cap screws) is how it left the factory, the original balance factor was:

294.7 + 260.0 / 505.0 + 260.0 = 455 / 765 = 60.2 +/-1%

If the four 5/16" holes were added later it would have required 38.9 grams less to balance it originally. In this case the original balance factor would have been

165 + 260 / 505 + 260 = 425 / 765 = 55.6 +/-1%

For comparison, a 1960 BSA Service Bulletin shows 60% for the 250cc 'C' series, 58% for Gold Stars, 55% for the essentially identical 'B' series singles in the same frame as the Gold Star, and 55% for both the 500cc and 650cc 'A' series twins, also in the same frame as the Gold Star. A 1930s Vincent Comet used 66% (claimed weight 390 lbs. vs. 290 for the Ariel) but this had to be reduced to 61% in a lightweight speedway frame.

Current Balance Factor:

With current piston in it:
196.6 + 267.5 / 467.5 + 267.5 = 464.1 / 735 = 63.1% +/-0.3%

With Gandini piston in it:
196.6 + 267.5 / 516.5 + 267.5 = 464.1 / 784 = 59.2 +/-0.3%

With Omega piston in it:
196.6 + 267.5 / 435.0 + 267.5 = 464.1 / 702.5 = 66.1 +/-0.3%

To reduce the balance factor to 60% in order to use the Omega piston in it would require reducing the required balance weight by 43 g which in turn would mean removing roughly half that weight from the rim of the flywheel. This could be achieved by, for example, drilling two additional 5/16" holes approx. 1" deep each.

If the Omega offered a significant advantage over the Gandini I would modify the crankshaft accordingly. However, since the Gandini piston could be used with the crankshaft as-is, I'm particularly interested in any experiences people have with these aftermarket pistons.

--------------------
Sidebar: The difference in weight of the bronze in an original 1" ID bushing and the current 13/16" reducing bushing in the small end:

Density of steel = 7.75-8.05 gram/cm3
Density of bronze = 8.7 grams/cm3
Width of connecting rod = 0.87"
Width of current reducing bush = 1.065" (tapered)
OD of bush = 1.1875"
ID of original bush = 1.000"
ID of current bush = 0.8125"
From this, the excess weight of the small end over that with the stock bush = 7.4 g
---------------------
Posted By: George Kaplan

Re: 1928 Ariel Model C - 12/17/17 10:46 pm

Hi MM, this is very interesting stuff indeed. I will be following how this develops because I am both interested in your progress on your Ariel both now in the preparation stage and also when you take it across country. I am a firm believer in meticulous preparation being the key to a successful outcome in the Cannonball and I am hoping that you willprove this to be true.

I am also interested because I am currently pondering the building a balancing rig of my own (and your input to my questions on my option is very much appreciated).

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/18/17 1:06 pm

Offline someone asked about the source of the equation I used for the balance factor. It, and the percentages I quoted for various BSAs, comes from BSA Parts and Service Bulletin No. 51, dated 1 October 1960.

The balance factor is the fraction of the ratio of reciprocating weight to rotating weight that is to be balanced, e.g. 60%. If the crankshaft is apart the rod is suspended horizontally and the little and big ends weighed separately (the sum needs to be the total weight or you've made a mistake). The weight of the little end, along with the piston assembly, is assumed to be reciprocating weight and that of the big end is part of the rotating weight.

Phil Irving describes in words the same equation as in BSA's Service Bulletin in a section entitled "Balancing a Complete Assembly" in a chapter on "Truing and Balancing Flywheels" in 'Tuning for Speed'. He also describes how if the crankshaft is together, and if it has a roller bearing (so friction is small), the little end can be weighed by rotating the crankshaft until the rod is horizontal. This is how I weighed the little end of my engine. The weight of the big end is "automatically" included by the procedure for balancing the crankshaft.

Further on the subject of balance factors, in the same book Irving writes:

"There are in fact so many considerations involved that it is impossible to quote one figure as being ideal, since it varies with every type of engine, and even for the same engine in differently-equipped frames. The only source of reliable information is the parent factory who have certainly done a lot of experimentation. The M.O.V. Velocette factor is as high as 85 per cent, while some engines have been under 50 per cent, but failing any reliable information 66 per cent is a good starting-off point."

It takes a lot of time to accurately balance a crankshaft so if I were rebuilding a stock engine using OEM components I probably wouldn't have bothered (then again, I have the equipment and the inclination for making such measurements, so...). But, the previous rebuilder of my engine bodged enough things that I didn't feel I could trust what he had done. For example, I certainly wouldn't have purchased a new Alpha crankpin to have on hand and be taking the crank apart if I trusted the previous work. Further, the two aftermarket pistons are significantly different in weight so even without making any measurements on the crankshaft I knew they would result in significantly different balance factors (59% and 66%, as it turned out). Now knowing that the original balance factor was ~60%, and since the Ariel is in the same stock configuration as when sold, it means that if it vibrates itself apart at 60% I can curse Val Page for his design and testing, not myself for having simply slapped one of the aftermarket pistons in and hoped for the best.

Returning to my measurements, earlier I mentioned that metal had been drilled from one flywheel at 90o, indicating that there was an inhomogeneity in the casting causing an off-axis imbalance. Another hole is drilled at 135o, indicating that someone didn't quite know what he was doing (balancing holes should be orthogonal to each other). I had to add a 10 g weight at 90o to get the flywheel to balance. Since I've come this far I will be drilling a shallow hole to eliminate that slight off-axis imbalance. This probably will involve a couple of iterations of drilling, rebalancing, drilling again,...
Posted By: koan58

Re: 1928 Ariel Model C - 12/18/17 9:10 pm

Hi Mr M, I am following your journey with fascination, and what your accounts inspire me to investigate some subjects more deeply. I am well versed in science, but I haven't given full depth of thought to this matter till you presented it in such interesting terms. Thanks!

"A seldom discussed but fundamental issue with the static balance method as usually described is it relies on the center of mass of the flywheels being on the axis defined by the crankpin and crankshaft. If an inhomogeneity in the flywheels places the center of mass off that axis then adding weight to the hanging connecting rod (which in effect places that weight at the center of the crankpin) will draw the center of mass close to the crankshaft axis but can never precisely balance the flywheels. To achieve perfect static balance requires applying weight to the connecting rod to draw the center of mass to its point of closest approach to the axis of the crankshaft, then adding (or subtracting) additional weight from the flywheels at 90-deg. from the crank-crankpin axis."

I don't understand the above bit. Say you were aiming for 50% (or any factor), you would hang a weight off the big end journal of a mass of your rod big end mass plus 50% of the piston + small end mass.
A flywheel, or balance weight, is not meant to be balanced, not in a simple spinning sense anyway. How will you balance the flywheels? Dave
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/18/17 10:17 pm

Originally Posted by koan58
I don't understand the above bit. Say you were aiming for 50% (or any factor), you would hang a weight off the big end journal of a mass of your rod big end mass plus 50% of the piston + small end mass.
I agree that if you separately weighed both ends of a rod and used those values in a slightly different version of the equation you could achieve whatever balance factor you wanted.

But, you also can do it the way I described. Even though I don't know the mass of the big end of the rod (because the crank is still assembled) its mass is attached to the crankpin so is automatically taken care of when I hang additional mass off the small end to balance the crankshaft. The only difference between the two ways of doing it, disassembled vs. assembled, is I probably could determine the small end weight a little more accurately if I had the rod separate from the crankshaft rather than still attached.

I'm not sure I understand what you wrote below:
Originally Posted by koan58
A flywheel, or balance weight, is not meant to be balanced, not in a simple spinning sense anyway. How will you balance the flywheels?
A flywheel definitely can be balanced in the simple spinning sense. That is, weights of the correct mass can be attached in the correct location on the crankshaft/crankpin axis (and, if necessary, 90o to that axis) such that when you spin that flywheel there will be no vibration. This is exactly what I did when I hung weights off the little end of the connecting rod. If instead of having those weights attached to the rod, which would flop around if I tried to spin the crankshaft, I removed the rod and welded to the crankpin its full weight plus the weight hanging from the small end, the crankshaft could be spun without vibration.

Did what I wrote above answer your question? If not, please rephrase it.
Posted By: koan58

Re: 1928 Ariel Model C - 12/19/17 6:05 pm

Thanks MM for your patience! I think some my my difficulty stems from terminology so leading to talking at cross-purposes.

I had trouble understanding "it relies on the center of mass of the flywheels being on the axis defined by the crankpin and crankshaft". Having mulled over it, I think you are referring to the plane thus defined. Yes? I can see how inhomogeneity (ie a difference in mass distribution of the flywheels either side of the above plane) would shift the flywheel's centre of mass off that plane.

If I may posit an imaginary, but possible scenario as illustration:

Left flywheel's inhomogeneity results in its center of mass being X" forward of the plane at TDC.


Right flywheel's inhomogeneity results in its center of mass being X" rearward of the plane at TDC.

Assuming the flywheels are of equal mass, in the static balancing process, the crankshaft overall centre of mass will be on the plane, but may result in a significant rocking couple in use.
Without individually balancing the flywheels with respect to the plane, there could be any combination of fore and aft imbalances with a net crankshaft imbalance which can be corrected by adding 10g to either flywheel. Depending on your luck, the 10g may reduce or increase any rocking couple already present.

This is what I meant by "how will you balance the flywheels?". I meant each one individually, not as a crank assembly, and is also what I meant by "A flywheel, or balance weight, is not meant to be balanced, not in a simple spinning sense anyway".

With the kit at your disposal, your fastidious approach, and that you will be parting the crank assembly, I imagined that you would be doing this somehow.
I don't know if you can use your kit to do this with individual flywheels, hence my question "How will you balance the flywheels?".

Another thought, knowing how accurately you like to do things (most admirable and why I find your posts interesting), when you are making allowances for holes in the flywheels, heads of bolts etc, doesn't the effect of these masses have to be adjusted according to their distance from the crank axis?
For example, the balancing weights act at the centre of the crankpin (half the stroke from the crank axis), holes on the periphery of the flywheels are further away and will have a greater impact.

Finally, a little curiosity. The holes in the flywheels drilled inside the rims, are they drilled from the crank axis outwards (ie radial) or in line with the axis?
Either way, I can't see why they would choose to do it there, and if it is the radial style it just occurs to me that in use they would be filled with oil, and over time act like sludge traps. Of little consequence, but odd? Dave
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/19/17 9:31 pm

Originally Posted by koan58
Assuming the flywheels are of equal mass, in the static balancing process, the crankshaft overall centre of mass will be on the plane, but may result in a significant rocking couple in use.
Making a long story short, yes, there certainly could be a rocking couple in a single. However, in a practical sense it's a matter of how big it could be. In the case of a twin the crankpins and the reciprocating masses are 3-1/2" apart (pre-unit Triumph), while for my Ariel the crankpin and reciprocating mass are on the centerline and the flywheels are at only 1-3/4" from it.

One or both flywheels might not be perfectly homogeneous from side-to-side and only dynamic balancing would detect that if it were the case. However, the maximum amount of such inhomogeneity in the steel is so limited, and the flywheels are so narrow, that the rocking couple it could produce would be pretty small.

While I could have each flywheel dynamically balanced, the vibration from any rocking couple would be so much smaller than the vibration that is going to come from the 60% balance factor that it wouldn't worth the effort to eliminate it.

Originally Posted by koan58
I don't know if you can use your kit to do this with individual flywheels, hence my question "How will you balance the flywheels?"
Once I have the flywheels apart I'll make a shaft and a weight of exactly half that of the crankpin + rod + piston assembly + balancing weight. With this I will be able to individually balance each wheel. I'm not so concerned with getting to, say, 60% vs. 58% but rather in getting rid of the problematic imbalance at 90o. The latter only causes vibration without doing anything to balance the engine. Unlike the case of the possible small rocking couple, ~10 g spinning at 3000 rpm generates significant vibration.

Originally Posted by koan58
when you are making allowances for holes in the flywheels, heads of bolts etc, doesn't the effect of these masses have to be adjusted according to their distance from the crank axis?
Most certainly yes. For example, the cap screws locking the crankpin nuts are at the same distance from the crank as the crankpin and big end so every gram they weigh is one less gram I don't hang from the small end. If, instead, these screws were at the rim every gram would be equivalent to ~2 grams at the crankpin.

Originally Posted by koan58
The holes in the flywheels ... in line with the axis?
They're in line with the axis.
Posted By: koan58

Re: 1928 Ariel Model C - 12/20/17 8:57 pm

Thanks MM for that, do please tell me if you find my questions and thoughts an annoying distraction.

I fully agree that the relatively compact crank assembly will considerably reduce the significance of any rocking couple. However, I think you may be overlooking the opportunity you have to do your best about it, at the same time as you are doing what you intend anyway.

You are quite right to say that only dynamic balancing would allow correction of the rocking couple of a crankshaft assembly, complete. For instance, I could only get my 1-piece triumph twin crank done by using the services of a specialist with the sophisticated equipment that spins the crank and records the cycles of loadings at both ends. This is because the individual contributions of the counterweights either side could not be isolated any other way.

In your case, you will split the crank, and will be individually dealing with each flywheel, using half the total balance weight, such that you will achieve an equal balance contribution from each wheel, and correcting for any orthogonal imbalance at the same time.
To me, you are 3 parts of the way to dynamic balancing.

You will have moved their centres of masses to the plane defined by the crank and big end axes. You will also have moved their centres of masses to the same radial points on that plane. The only remaining factor that could cause a rocking couple is a difference between the masses of the flywheels. So if the centres of mass and the actual mass of the wheels are the same, that is dynamic balance.

I assume that the flywheels are pretty much similar, however we know that their mass distribution is not perfect, so it is also quite likely that their masses are different. It only remains to establish the masses of the wheels, then you can equalise them at the same time as putting their mass centres in the same place.

Of course, ascertaining the masses of the flywheels is not simple, as they have different shafts attached to them. I would start by weighing each flywheel unit. Then make an allowance for the shaft weight.
If those shafts are simple, an allowance could be calculated based on dimensions/density. Alternatively, Archimedes could be used. If the wheels come out fairly close, it's probably not worth fussing about.

A couple of separate thoughts:

"If the four 5/16" holes were added later it would have required 38.9 grams less", I couldn't see where and how this was applied in the calculations?

I think the calculation of the mass difference between small end bushes may need revisiting.

The difference in X-area between the bushes is 3.799 (current) - 2.077 (original) = 1.722 cm2

A length 2.21cm (width of conrod) of this difference produces 3.806 cm3, X 8.7 g/cm3 (density of bronze) = 33.109g

If the length of the current bush is longer (2.705 cm) than the original (2.210 cm?) this discrepancy is even larger (approaching 50g)

You only have to visualise how small 7.4g of bronze is (less than 1cm3) to see something is amiss.

Only playing devil's advocate! Dave
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/20/17 9:47 pm

Originally Posted by koan58
To me, you are 3 parts of the way to dynamic balancing.
The weights of the webs and reciprocating weights of the crankpins, and the separation between them, of a twin make that situation significantly different than that of a single. Sometimes the pursuit of perfection gets in the way of achieving more-than-good-enough. I think dynamic balancing of the individual flywheels of a single is one of those times.

Originally Posted by koan58
If the four 5/16" holes were added later it would have required 38.9 grams less", I couldn't see where and how this was applied in the calculations?
I'll double-check my calculations later to see if I made a mistake in either the calculation or in retyping it for my post.

Originally Posted by koan58
I think the calculation of the mass difference between small end bushes may need revisiting.
I didn't give the details, but the present bush isn't simply a hollow cylinder. It has the dia. of the little end through the cross section of the connecting rod, then tapers to a smaller OD out to nearly the open space inside a piston. But, I'll double-check those calculations later as well.


The Ariel manual calls for the crankshaft spindles to run "dead true," and various sources say to aim for no more total indicated runout (TIR) than 0.001", so before disassembling it I wanted to know how close to dead my crankshaft currently is. It turns out to be much too alive for its own good, yet again justifying my complete rebuild of the bike.

With the crank between centers, the total TIR is 0.006" on the drive side spindle measured next to the flywheel, 2.9" from the closest center, and 0.003" at 0.5" from the center, consistent with the center at that end being, ahem, drilled off-center by ~0.001" (for a TIR of ~0.002"). The same measurements on the timing side are 0.008" at the flywheel, 2.4" from the closest center, and 0.0015" at 0.5" from the center, consistent with the center at that end being exactly on-center. This means a perfectly straight shaft with perfectly drilled center at one end and a center off by 0.001" at the other would measure 0 TIR at the timing end, 0.001" in the middle, and 0.002" at the drive end.

I'll recut the center at the drive end once I have the crankshaft apart and can hold that spindle in a 4-jaw chuck. But, for now, knowing how much TIR a perfectly straight shaft should have with one center off by 0.001" I can determine how well my crankshaft is currently trued. Unfortunately, as noted earlier in the previous paragraph, rather than 0.001" in the middle the TIR is ~0.006"-0.008".

I marked all the points of high and low readings for all of my measurements from which it appears both spindles are straight, not bent. However, the ~0.008" TIR near the center says something is wrong.

The TIR of the side of the drive-side flywheel near its outer rim is 0.0075" and of the timing-side flywheel is 0.006". These faces are 4" from the crankshaft axis. The spacing between flywheels varies by 0.012" with it a maximum at the same orientation where the spindles come closest to the indicator.

Within measurement uncertainties all of the above is quantitatively consistent with the two spindles being straight and mounted "perfectly" in their respective flywheels, but the flywheels held together by a crankpin that is ever so slightly angled in the flywheels. As a result, the previous rebuilder installed a crankshaft that has a TIR ~8x larger than is acceptable.


Attached picture IMG_6355.JPG
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/21/17 2:31 pm

I now have the crankshaft apart. It took ~130 ft.-lbs. to loosen one of the nuts and ~160 to loosen the other. I was surprised the torque was so small since my notes show 200 ft.lbs. is used on the same size nuts on the crankpin of a BSA B44. After slipping two 1/2" steel bars between the flywheels, 2" spacers to elevate them, and two additional bars to catch the falling flywheel, it then took 3000 lbs. from the press to pop the crankpin loose from one flywheel (not necessarily the same side as the 130 ft.lbs. because I didn't keep track of which was which) and 3800 lbs. for the other.

Although I could have hit it with as much as 30T, a 2T press would have been (barely) sufficient. I can't remember having seen these figures before, which is why I've listed them here in case someone else faces this job and needs to know if their press will be sufficient.

The crankpin was in good shape with no issues whatever with the race or rollers. The absence of up-down clearance of the rod and the tiny amount of polishing of the center of the race implies the crankpin has seen very limited use, i.e. it is essentially new. I'll pack it with the other spares for the Cannonball, but if it reaches the point where a replacement crankpin is needed in order to continue, I'll be booking a flight home...

There are two holes in one of the tapers of the crankpin whose reason for existence I don't understand because there are no holes in the corresponding taper in the flywheel. These are separate from the hole that's present to feed oil to the big end. The Alpha crankpin has the same two holes in one taper, but the crankpin that was in the bike isn't an Alpha. Stamped on its end is RH L171. Since Alpha supplies the same crankpin for some later Ariels perhaps those mystery holes are there to perform a function in them.

With the rod freed from its former duties I put it on the surface plate. It's twisted horizontally by 0.017" over the length of the crankpin, which is no big deal, but also bent in the up/down direction by 0.017" which is a problem. I'll set up a different measurement to see if that's due to a simple, slight bend in the rod or if the bush at the top was pressed into place and reamed slightly askew. It wouldn't surprise me if the rebuilder installed and reamed it without taking the crank apart, which easily would explain the problem. Either way it has to be fixed because otherwise it would force the piston to rub on the cylinder (unless I have it bored with 0.018" clearance...). No matter what I planned to make a new bush myself using the bronze Chaterlea25 sourced for me (again, thanks) so I'll try to take a bit more care than the previous rebuilder did. Conveniently, both sides of the big end are machined surfaces so I'll be able to clamp that end to the bed of the mill for drilling and reaming of the new bush after it's pressed into place.

With the separate crankshaft components now laid out on the workbench I'll fire up the Magnafluxer to inspect them. Also, I still need to plate the 0.001" of Cu on the C3 drive-side bearing that gunner located (again, thanks) for a proper interference fit.

Aside from the above, it's now going to be mostly machining work for a while to get a variety of crank and cam bushes fabricated, crankshaft axis line bored, cylinder base and crankcase mouth decked, and cylinder bored (plus, whatever else I've forgotten). Once all that is done I'll be ready to assemble the bottom end of the engine and then turn my attention to the head.

Meanwhile, the "high" (i.e. closer-ratio) gear set is winging its way to me from the UK with tracking showing an estimated delivery "no later than 4 January." Even an optimist wouldn't predict I could be ready to start on the gearbox by then, but everything should be in place once I get to that task.


Attached picture IMG_6357.JPG
Attached picture IMG_6358.JPG
Posted By: L.A.kevin

Re: 1928 Ariel Model C - 12/21/17 6:24 pm

Originally Posted by Magnetoman


With the crank between centers, the total TIR is 0.006" on the drive side spindle measured next to the flywheel, 2.9" from the closest center, and 0.003" at 0.5" from the center, consistent with the center at that end being, ahem, drilled off-center by ~0.001" (for a TIR of ~0.002"). The same measurements on the timing side are 0.008" at the flywheel, 2.4" from the closest center, and 0.0015" at 0.5" from the center, consistent with the center at that end being exactly on-center. This means a perfectly straight shaft with perfectly drilled center at one end and a center off by 0.001" at the other would measure 0 TIR at the timing end, 0.001" in the middle, and 0.002" at the drive end.


Just from experience in my industry (electromechanical aircraft parts), centers are often a source of error. For really critical measurements, parts are clamped in v-blocks on the bearing journals using packing tape on the v-block and a Teflon end on the machinist clamp to protect the journals. Many times, I've found that there has been error by relying on the non-functional shaft end center to measure run-out. You've probably thought of this, M-M, but I just wanted to remind you. Centers can be used, but you really have to check to make sure they run true. I found the worst cases of this sort of error is when live centers were used and different bearing journals have been cut on different machines.
Posted By: chaterlea25

Re: 1928 Ariel Model C - 12/21/17 6:44 pm

Hi MM,
Re the big end nut torques ?
Does it take the same ft/lbs to undo a nut as to tighten it ?
I don't believe so? I think that the metal yields a little over time after tightening ??
The Ariel flywheels are cast where as the B44 wheels are steel so friction /grip and yield of the metal will be different
Recently I rebuilt a couple of Indian Chief engines, The torques for the big end and main shaft nuts is 100ft/lbs when the engine has
"Z" metal flywheels, non "Z" flywheels get 70/75 ft/lbs
These pins and shafts do not have shoulders though ( I could go and check thread size and pitch on the old parts if needed)
With shouldered pins the shoulders need to to seat against the flywheel when fully tightened,
a gap between pin shoulder and flywheel when fitted by hand is essential so the grip is taken up by the taper

Final torque value is not a fixed figure I believe
Whatever the nuts need to pull the pins against the shoulders, +
Of course the flywheel taper bores stretch every time the pins are replaced which does not help when fettling old engines
From The figures that you measured to release the tapers it looks like the flywheel bores are in good order though

I prefer to not rely on the mainshaft centres, but set up the assembly on bearings and v blocks instead

I believe it would be very difficult to evenly plate the main bearing ? the surface of the copper plating will not be smooth ?
I believe that you need to plate oversize and machine to the desired figure
I think I would have gone the route of a steel sleeve on the bearing as you had the case set up on the milling machine ??

Always more than one way to skin a cat!!!
John




Posted By: George Kaplan

Re: 1928 Ariel Model C - 12/21/17 9:27 pm

Hi MM, I cant help with the balancing or truing of your crankshaft but I was just reading the last few posts and it occurred to me that this could be the first time that anyone has blueprinted a 1928 Ariel engine.

John
Posted By: old mule

Re: 1928 Ariel Model C - 12/21/17 10:09 pm

George, now everyone will want it done!
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/22/17 4:10 pm

Originally Posted by George Kaplan
this could be the first time that anyone has blueprinted a 1928 Ariel engine.
Including on the factory assembly line...

Originally Posted by chaterlea25
Does it take the same ft/lbs to undo a nut as to tighten it ?
Ah, of course your explanation must be correct.

Originally Posted by L.A.kevin
Just from experience in my industry (electromechanical aircraft parts), centers are often a source of error.
Originally Posted by chaterlea25
I prefer to not rely on the mainshaft centres, but set up the assembly on bearings and v blocks instead
I agree with both of you, and I won't be relying on the centers when I assemble the crankshaft. Both centers are (were) rusty and probably have been hammered on so it's surprising they're as close as they are. However, they served my purpose better than a V-block would have for characterizing the current condition of the crankshaft.

The limitation is that the ends of each shaft aren't useable for precision measurements because of threads and splines. Had I held the crank next to the flywheels, as I did for balancing, I only would have been able to measure the runout fairly close to where it was being supported which would have disguised the degree of misalignment. Holding it by the centers, after having determined how off-center the centers were, allowed me to make better measurements of the deviations from being straight. Again, this was just for the purpose of seeing what the crank was like as-received, not for the highest precision reassembly. That said, centers can be useful so I've already recut the off-center center after centering it to better than a half-thou., the best I could achieve given the less than perfect surface of the spindle. Whether or not I'll want to use that center in the future remains to be seen, but now it's in good condition in case I do.

Originally Posted by chaterlea25
I believe it would be very difficult to evenly plate the main bearing ? the surface of the copper plating will not be smooth ?
I haven't done it yet but I don't expect this to be a problem. I'll curve the Cu anode into a cylinder, and anyway the bearing will be an equipotential surface, so the plating will have no choice but be uniform. I expect it will be smooth as well, but that's not an issue. With the case heated to 100 oC and 0.001" of Cu on the bearing it should drop right into place. The Al will then close up on it when it cools to hold it in a death grip thanks to the 0.002" interference fit.

I'll plate for half the time I've calculated it should take and measure the progress at that point. Based on that measurement I'll adjust the remaining time, if necessary to give the 0.001" thickness (0.002" increase in diameter) I'm looking for.

Bearing steel is high strength and thus especially prone to hydrogen embrittlement. Based on the best information I could find, immediately after plating I'll toss the bearing in an oven at 375 oF for a full 24 hours to eliminate the hydrogen.

Originally Posted by chaterlea25
I think I would have gone the route of a steel sleeve on the bearing as you had the case set up on the milling machine ??
Always more than one way to skin a cat!!!
When possible I try to err on the side of removing the least amount of material I can since, generally speaking, material can't be put back once it's removed. Also, a sleeve is a more complicated solution. As long as there is a 0.002" interference fit, either of bearing in housing or of bearing in sleeve in housing, what could possibly go wrong?...

On the subject of plating, I originally convinced myself that pits in the shafts at either end of the camshaft only degraded a small enough fraction of the surface area that they wouldn't be a problem. Unfortunately, I couldn't keep myself convinced of that.

Figuring out how deep the pits are, and hence how thick a layer of hard chrome plating would need to be, took a bit of effort. I easily could have used the depth of focus on a standard microscope to determine the depth of the pits (the z movement of the stage is calibrated in microns). But to do that the cam would have fit in the space under the objectives, which it doesn't. My inverted microscope was no good either because the gear on the cam doesn't let the surface in question lie in the right plane.

I then decided to see if I could use an old surface roughness gage as a "secondary standard" to make an estimate, but I immediately discovered there are no units for the numbers on it, i.e. are they microinches or microns, and are they average roughness values Ra or peak-to-peak roughness values Rz which are ~4-10x larger depending on the degree of randomness of the roughness?

So, using a profilometer I determined the numbers engraved in the gage are a reasonable match to Ra in microinches. I then compared the visual "depth" of the various patches on the gage with the appearance of the pits on the cam and decided a certain patch engraved 500 microinches was a reasonable-ish match. However, converting from Ra to Rz for non-random surfaces is problematic so I then put the gage in the microscope and determined the depth of the grooves in this patch is around 30 microns (~0.0012"). As a check I then used my profilometer on the gage to display Ra (356 microinches, vs. the 500 engraved on the gage) and Rz (0.000992"). I count the latter as better than perfect agreement with my visual determination/estimate.

The above "only" took ~45 minutes away from doing anything tangible to determine I need to deposit ~0.001" of hard chrome to fill all but the deepest of pits. This is convenient because currently the diameter of the shaft at one end is 0.7462"-0.7470" and at the other is 0.7460"-0.7465". Using the rule of 1.5 thou./inch for the proper clearance between a shaft and bush each of these has to be built up by ~0.002" in diameter (i.e. ~0.001" Cr thickness) to properly fit in bushes that are reamed to 0.7500". This is well within the ~0.006" thickness the web tells me is reasonable for hard Cr so a hard Cr plating kit is already on its way to me.

I'll probably end up plating ~0.002" and then grinding back to size using my toolpost grinder. As with any plating hydrogen embrittlement is a problem, and it appears it's especially bad with Cr. Although the cam isn't made from high strength steel I'll still bake it for a full 24 hours at 375 oF immediately after plating. First, though, I'll need to find something to "paint" most of the cam with that's easy to remove afterwards, in order to leave only the spindles at both ends exposed for plating.

As an aside, the cam lobes show no sign of pitting so they've been ground at some time in recent history. I've yet to measure the base circle and lift to determine what changes might have been made to them (assuming I can find or infer the original values).
Posted By: George Kaplan

Re: 1928 Ariel Model C - 12/22/17 5:09 pm

Hello MM, I am following your progress with interest and quite often have a few questions and sooner or later you inevitably answer them before I ask them. You mention in your last update that, for the hard chrome plating, "I'll need to find something to "paint" most of the cam with that's easy to remove afterwards". Before you mentioned that I was wondering how you intend to mask the bearing before copper plating it so that you only plate the outer surface that you want to increase the size of?

I was thinking of sandwiching the bearing between two custom made washers that would leave the outer surface exposed. This would also provide a way of holding the assembly in the plating tank. Or do you have some other arrangement in mind?

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/22/17 9:26 pm

Originally Posted by George Kaplan
I was wondering how you intend to mask the bearing before copper plating it so that you only plate the outer surface that you want to increase the size of?
Keeping in mind that I haven't yet plated the bearing, so what follows needs to be taken with a grain of salt for now, I simply used Kapton tape to cover the sides. Although I had no doubt the tape would resist water, I tested it anyway by sticking a piece to a chunk of steel and letting it sit in a beaker of water for a few hours. For the electrical lead I wrapped one turn of brass wire around the outer surface (the one that will be plated) and tightened it with safety-wire pliers. That will leave a narrow line of unplated steel under the wire, but the area of that line will be negligible. While the tape and wire work for the simple geometry of a flat-sided bearing where an unplated line doesn't matter, the cam will require a different masking solution.

I was getting ready to plate yesterday but at that point discovered that whereas the ad for the Caswell "Flash Cu" kit I bought said it "can be used to plate copper over steel, zinc, pot metal, ..." the sheet of instructions that came in the box said it "should not be used on steel, zinc, iron..." I called the tech rep today and he confirmed the ad is correct (i.e. it can be used), and that the instruction sheet is for their "Acid Cu" kit. Anyway, meanwhile I had ordered their hard Cr kit which will come with a 180-page manual so I decided to wait until that shows up in case it contains helpful information. I should have no problem filling my time for the next week with other work that needs doing.

I've done electroplating three times I can think of over the past 40 years so this isn't my first venture into it. Although the principle is very simple, producing the best quality results requires a witch's' brew of additives, a current density for the given material that is neither too high nor too low, the right temperature range, the proper surface "activation," etc. Since I don't want to take the time to reinvent the process, I just want to plate the parts with a minimum of time and effort, the premium paid for the chemicals in proven kits is well worth it to me.
Posted By: gREgg-K

Re: 1928 Ariel Model C - 12/23/17 1:30 am

I just had an idea about how to mask the bearing ID while leaving the entire OD of the bearing race open for plating. Protect the bearing with two disks attached to the bearing's open "faces" by a through bolt, with one disk on each face. If need be, the disks could also be sealed to the edge of the bearing race.

If the disks are metal, they could additionally serve as the electrical contact for the lead to the power supply.

Workable?
.. Gregg
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/23/17 5:51 pm

Originally Posted by gREgg-K
If need be, the disks could also be sealed to the edge of the bearing race.
If you cut the disks to size and found a way to seal their edges as well as the bolt hole it certainly would work.

I already knew from measurements I made a few months ago that the cylinder bore was slightly tilted from being perfectly perpendicular to the base of the muff. The base of the mounting flange also was slightly warped and heavily pitted from rust that had been cleaned away and painted over.

To get the cylinder back into shape, yesterday I machined a 1"-thick steel plate to be flat to a half-thou. and bored holes in it so I could bolt to the top of the cylinder. Since the sleeve projects above the muff to form the mounting surface for the head this meant the top of the steel plate was parallel with that surface. I then mounted this assembly in the four-jaw chuck and adjusted the runout of the inner surface of the lower end of the cylinder to be ~0.001". Since I already knew the bore of the cylinder was tilted in the muff it would have been better to center it on the OD, but that surface is too rough to use for this to any degree of accuracy. Anyway, with the centering I did it was possible to skim the base of the mounting flange to within no worse than ~0.01" of the outside edge of the cylinder which is good enough for it to fit in the cases.

I had to remove from 0.015" from the base to get it flat, i.e. parallel with the top, mounting flange. This also was enough to remove all but a few of the deepest pits. When centered on the ID of the cylinder the runout of the OD was ~0.01" consistent with my measurements of a few months ago from which I inferred the cylinder had been (incorrectly) bored by placing it upside down on a boring bar rather than properly right side up. Now, after machining, when I placed the cylinder upside down on the surface plate and ran an indicator around the mounting flange I found the surfaces parallel with each other to within a half-thou. side-to-side. I'm calling that good enough...

Once the mouth of the crankcase is faced to be accurately parallel with the crankshaft axis the piston will go up and down as it should without being forced back and forth sideways toward the cylinder wall on each stroke.

The cylinder is now ready for boring, to be supported by parallels under the base flange and with a torque plate (that I made a few months ago) bolted to the top plate. However, before doing that I'll need to revisit my balance factor post to look for the error koan58 said he found, to see if it affects my choice of which piston to use.

Returning to the crankshaft, I mounted the two halves by their shafts in the lathe and measured the amount of wobble of the sides of the flywheels. The timing side wasn't perfect, but wasn't awful at 0.003". However, the drive side was 0.016". Even if the crankpin went into its tapers perfectly straight these shaft would make a pretzel of the assembled crankshaft. I don't have experience with this but I hope this large amount of wobble can be corrected by careful reassembly and doesn't mean the tapers have been permanently distorted.

In both cases the orientation of maximum wobble was opposite to the crankpin. What this means is with the mounting of the crankpin slightly crooked it would be possible to reduce the runout of the shafts on the assembled crankshaft to roughly the average of the 0.003" and 0.016", i.e. to ~0.010", when supported on the centers and measured next to the flywheels. Not coincidentally, in a post a few days ago I determined that to be ~0.006"-0.008". Showing, if nothing else, that two wrong actually can make a (almost) right...

Clearly, there isn't a nut or bolt on this bike that isn't going to be unmolested before this rebuild is finished...


Posted By: kommando

Re: 1928 Ariel Model C - 12/23/17 6:21 pm

Quote
If you cut the disks to size and found a way to seal their edges as well as the bolt hole it certainly would work.


End rod seals, these are dished, rubber on the OD and steel in the centre.

https://sealsit.com/product/ws1000-rod-end-seal/

[Linked Image]
Posted By: Alan_nc

Re: 1928 Ariel Model C - 12/23/17 8:41 pm

Slightly off topic:
Bore: Why does it matter which end you bore a cylinder from if - you are holding on a surface with a known relationship to the cylinder and you are allowing for any error?
Posted By: George Kaplan

Re: 1928 Ariel Model C - 12/23/17 9:54 pm

Originally Posted by Magnetoman


I don't have experience with this but I hope this large amount of wobble can be corrected by careful reassembly and doesn't mean the tapers have been permanently distorted.



Unfortunately I don't have experience in this either but I did watch these two youtube videos recently:

https://www.youtube.com/watch?v=GfcUFelP5_w

https://www.youtube.com/watch?v=NyHRnba50fI

The second one shows lapping of a crankpin to correct a misalignment where it fits in the flywheel which was picked up in the first video. It occurs to me that a similar technique could perhaps be used in your situation except you are correcting a issue with the shafts rather than the pin.

I am just guessing here but it might be worth checking out unless anyone has a better idea or if just careful reassembly reduces your run out to an acceptable level.

John
Posted By: Shane in Oz

Re: 1928 Ariel Model C - 12/23/17 9:59 pm

Originally Posted by Alan_nc
Slightly off topic:
Bore: Why does it matter which end you bore a cylinder from if - you are holding on a surface with a known relationship to the cylinder and you are allowing for any error?

It's the "if" which can bite. The bore needs to be absolutely perpendicular to the crankshaft so the piston runs parallel to the bore. Provided the top face of the crankcase is parallel to the crankshaft (and MM's will be), the bottom face of the cylinder flange is also parallel to the crankshaft and forms the reference face for boring.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/23/17 10:10 pm

Originally Posted by commando
End rod seals, ...
Thanks, but I'm set for now with the Kapton for the bearing but welcome ideas of a substance to paint on the camshaft that's insoluble in water but easily dissolves afterwards in acetone, ethanol, or whatever.

Originally Posted by Alan_nc
Why does it matter which end you bore a cylinder from if - you are holding on a surface with a known relationship to the cylinder
It doesn't matter if the top of the cylinder is accurately parallel to the base of the mounting flange. But, you can't count on that happening. Actually, it's best to count on it not happening. In the case of my Ariel I had to remove 0.015" from the base to make it parallel to the top face. Had I not done that, and if it were bored upside down. the cylinder would have ended up tilted by that amount with respect to the base. If that tilt all were in the side-to-side direction it would have forced the piston back and forth by that amount on each revolution.

It took ~150 ft.lbs. to loosen the nut holding the drive-side spindle then ~3800 lbs in the press to pop it loose.

With a torque wrench, big copper hammer, and more than a dozen trips between the lathe and vise, I now have the drive side wobble reduced from 0.016" to 0.0035". I torqued the nut in stages, each time measuring the wobble, marking with paint, and developing a calibrated hammer arm to whack it and remeasure to see what I had accomplished. Whacking components of a machine with a big hammer seems so very, very wrong.

I now hope someone like chaterlea25 with experience in such matters weighs in with advice on whether ~0.003" is enough for now, given I'll have to go through it again when the crankpin is installed, or if I need to continue until I get both shafts individually closer to 0.000" in order to ensure I'll be able to get the overall runout of the assembled flywheel no worse than 0.001".

While I had the spindle removed I used the opportunity to Magnaflux it and the flywheel. Both passed the test (I'll do the other flywheel/spindle and connecting rod later today, or tomorrow). I also used a wire brush and two hours in my favorite de-rusting solution to make the end of the spindle that sticks into the primary case look a lot better than it was.


p.s. several replies came in while I was composing my post off-line so I'll read them and watch those videos.

p.p.s. 0.016" at a distance 4" from the spindle means the the ~1" taper would have to have ~0.004" removed from it. Not only would that require a lot of lapping, it would make the taper too large for the spindle to fit without bottoming out on the shoulder before it was seated.
Posted By: koan58

Re: 1928 Ariel Model C - 12/23/17 11:19 pm

You're doing a cracking job MM.
I am relieved that you are taking the trouble to double-check the balance calculations. Ideally, another technically minded peep would work through it independently. However, most of it is straightforward, and any error should be obvious as you go through it again.
My query about the 38.9g was only that I couldn't see how it was being employed.
My point about the mass of the small end bush is absolute, and I wouldn't like you to make calculations based on a false quantity.

I first converted all of your dimensions into cm:

conrod eye radius R = 1.508 R sq = 2.274

ID of original bush radius Ro = 1.270 Ro sq = 1.613

ID of reducing bush radius Rr = 1.032 Rr sq = 1.065

Cross sectional areas:

original bush = pi X (2.274 - 1.613) = 2.077

reducing bush = pi X (2.274 - 1.065) = 3,798

X - sectional difference between bushes = 1.71 cm sq


Now, say both bushes are just the width of the conrod = 2.210 cm

Volumetric difference = 2.210 X 1.71 = 3.78 cm3 X density 8.7 = 32.9g


This doesn't allow for the reducing bush extending beyond the limits of the small end eye.


Hope it's helpful,
Dave
Posted By: gavin eisler

Re: 1928 Ariel Model C - 12/23/17 11:49 pm

I didnt see a 3rd finale to that lapping video, probably bell mouthed the female hole, the bigger OD cuts faster than the minor, where the paste goes is critical for lapping tapers. At work , the large machines ( 240 ton rotating mass, 500 rpm) were allowed 0.008" radial run out over a 26 foot shaft supported/ aligned by a taper fitted thrust collar, best I ever saw was 0.003 " , at 4 inches from the collar the runout would have been so low we would not have been able to detect it with the clocks we used.. The collar was stretched hydraulically and pushed down then retained by semi circular keys like giant circlip,
To seat the collar the weight of the machine was allowed to bear on it as the pressure from the expander gear was relaxed, usually with a decent bang . Sometimes we honed keys , other times we used shims, 2 thou max., if a key was out by a 1/10 of a baw hair it would throw the run out . Not quite the same scale though! Does illustrate how the top register fit will influence final run out.
Posted By: robcurrie

Re: 1928 Ariel Model C - 12/23/17 11:49 pm

Regarding a waterproof removable coating, Rustoleum make a flexible rubber spray-on coating which can be peeled off.

Rob C
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/24/17 12:15 am

Originally Posted by koan58
I am relieved that you are taking the trouble to double-check the balance calculations.
Even though I might not immediately act or reply to them, I definitely appreciate all input and suggestions. I'm certainly not proceeding in a linear fashion through this rebuild but there are limits to my ability to multitask and work in parallel. This means when I've put something aside I might need to leave it dormant for a while. Earlier this month I was in the UAE and from there to Australia so in the runup to that long trip I devoted quite a bit of my time to getting items ordered so they could start arriving while I was away. I wrote the draft of the balance factor post at 30,000 ft. and then checked it while still jet lagged after my return from having gone through 24 time zones so would be disappointed, but not surprised, if an error slipped through.

Originally Posted by robcurrie
Rustoleum make a flexible rubber spray-on coating which can be peeled off.
'Flexidip'. Thanks for pointing that out. It looks like it might be perfect, as long as it doesn't leave too much residue behind in the nooks and crannies when it's pealed off. I'll buy a can and try it. Thanks again.

The connecting rod passed the Magnaflux test, leaving the timing side spindle and flywheel yet to test.
Posted By: koan58

Re: 1928 Ariel Model C - 12/24/17 12:52 am

I'm not comfortable about the wire around the outside of the bearing. For one, it will have a higher potential than the bearing outer, distorting the migration, possibly even ending up welded to the bearing.

I'm trying to think of a way to put the cathode wires into a bearing, such that electrical contact is perfect to the outer race, without the wire itself interfering electrically.

I have a germ of an idea. Suppose the bearing is perfectly degreased. Then a multistrand copper cable is stripped back ~2", frayed out and the strands stuck in the bearing (maybe even anneal the strands) so that they jam between the balls and race, with a modicum of force to ensure contact. Wiggling back and forth with enough wires in enough places will get a jammed situation soon enough.
This will give a more even potential around the bearing.

Now the insulated wire must be embedded in wax, with the bearing.

Then carefully remove the wax from the perimeter, now I'm losing faith!

This plating business is easier said than done, for instance you don't want copper on the bearings, the tiniest leak will allow that to happen.
Interesting stuff.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/24/17 1:01 am

Originally Posted by koan58
t will have a higher potential than the bearing outer, distorting the migration, possibly even ending up welded to the bearing.
No, the wire will have precisely the same potential as the bearing. The plating potential is only ~4 V so the wire won't be welded to the bearing.
Posted By: koan58

Re: 1928 Ariel Model C - 12/24/17 1:31 am

MM,
No, of all people you should know that potential difference changes with resistance, so for instance 4V supply when it gets to the bearing, could be 3.9V.
Now, a 4V cathode vs a 3.9V cathode will make a difference, in ion migration.
All I am saying is that the wire should be insulated from the electrolyte. Dave
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/24/17 1:42 am

Originally Posted by koan58
potential difference changes with resistance,
Yes, but the contact resistance will be milliohms or less in air, let alone in a conductive solution, and the current less than 500 mA, so the potential drop will be less than a mV. This will have a totally negligible effect.
Posted By: koan58

Re: 1928 Ariel Model C - 12/24/17 2:29 am

Fair dinkum, lets see.
Where I'm coming from is to give you the best chance of an even coating of copper in the right place.
It is all about how charged particles move in an electric field.
A voltage of X will be imposed on the object, a similar voltage will exist on the wires leading to the object. The field around the wires will be more attractive to the cations than the more surface-rich object.
I do think that the feed wires should be isolated from the electrolyte, but this is new to me too, but I do want you to be successful! Dave
Posted By: Tridentman

Re: 1928 Ariel Model C - 12/24/17 2:48 am

"I'll curve the Cu anode into a cylinder"---from an earlier posting by MMan.
I would certainly recommend an anode exactly the shape of the outer bearing surface.
This will give as even a coating as possible. In my first job as a development engineer I was involved in electrochemical machining (the reverse of plating) and the electrode shape was critical in getting the desired results. We even experimented with electrodes that were moved during the process to achieve the desired result. Then did things like rotating the workpiece and made things that are impossible to machine using conventional means. Bit of a solution looking for a problem situation as we couldn't figure out a use for it!
Very far sighted organization---Friday afternoons were free--you could do anything using the companies facilities.
A couple of the things coming out of that were the automatic choke for carbs on cars and the first gas engine fuel injection system that was economic to produce.
But I digress----keep up the good work ,MMan.
Do you have the dates for the Cannonball Run in 2018?---particularly the start date?
Over Christmas I want to start planting some seeds about how nice a vacation would be in Maine next year!

Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/24/17 3:08 am

Originally Posted by Tridentman
Do you have the dates for the Cannonball Run in 2018?---particularly the start date?
The start will be September 8, but everyone will be there a few days before that.
Posted By: gunner

Re: 1928 Ariel Model C - 12/24/17 10:41 am

Regarding masking of parts being electroplated, one option is to use specialised electroplating masking tape, see This Link as an example.

It's claimed that this tape is resistant to all electroplating chemicals & solvents up to 170f, is abrasion resistant and has an adhesive rubber backing with excellent adhesion to most surfaces.

Available on Amazon see Link
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/24/17 3:17 pm

As 2017 draws to a close and the 2018 Cannonball draws rapidly nearer, best holiday wishes to everyone who has been following along on this thread. My special thanks to those who have taken the time to contribute. The Honor Roll of contributors, in order of appearance, for whom I hope Santa will be especially nice tomorrow (or today, if you're from down under), is:

robcurrie
kevin roberts
Adam M.
gRegg-K
gavin eisler
Triless
Shane in Oz
Richard Kal
Hillbilly bike
johnm
Stuart
Bruce Martin
Alan_nc
norton bob
Tridentman
RPM
JubeePrince
Villiers
franko
kommando
No Name Man
Lannis
edunham
KevinN
chaterlea25
Tribsauk
old mule
triton thrasher
George Kaplan
koncretekid
Rich B
gunner
koan58
L.A.kevin
(and apologies to anyone I accidentally left off this list)

Posted By: robcurrie

Re: 1928 Ariel Model C - 12/24/17 5:09 pm

Thanks MM and a Merry Christmas to you and yours as well.

Rob C
Posted By: gREgg-K

Re: 1928 Ariel Model C - 12/24/17 6:03 pm

Wishing you the best of luck in the challenge MM. Mind you, with the thorough preparations you are doing, not much luck is going to be needed!

.. Gregg
Posted By: gunner

Re: 1928 Ariel Model C - 12/24/17 6:24 pm

Best wishes MM, have a great Christmas and New Year, especially on the Cannonball run.
Posted By: koan58

Re: 1928 Ariel Model C - 12/24/17 8:35 pm

Thanks MM. Have a gold-plated time yerself! Dave
Posted By: gavin eisler

Re: 1928 Ariel Model C - 12/24/17 10:26 pm

Thanks for the thread, and have a great Christmas and New Year.
Posted By: Tridentman

Re: 1928 Ariel Model C - 12/24/17 10:38 pm

Merry Christmas, MMan and a Happy and Healthy 2018 with peak fitness and reliability in September 2018!
Posted By: L.A.kevin

Re: 1928 Ariel Model C - 12/25/17 5:37 am

This thread has been a great Xmas present to us all. Thanks so much for some excellent reading.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/26/17 11:45 pm

I decided to make my own 2-post version of an $800 crankshaft assembly fixture like the K&L.

The premise of such 2-post and 3-post fixtures is that if both crankshaft spindles are held precisely in line with each other when the crankpin is pressed into place the assembled crankshaft will have no choice but to have 0 runout. However, the design is at the mercy of tolerance buildup so I expect final tweaking of the crank will be required. If the holes for the spindles are oversized by only, say, 0.001" that alone would allow the centerlines of the shafts to be displaced from each other by as much as 0.002". Still, the closer the alignment is to start the easier it should be to get to the final result.

Commercial units like the K&L appear to be made from 2"-thick steel but I'm making mine from 1" because i) I have the steel on hand, and ii) it won't have to survive being operated by an uncaring mechanic. While thinner steel will bend easier than thicker, as described in an earlier post I've determined that less than 4000 lbs. will be required to press the Ariel crankpin into place. It appears Harley cranks require 3-4x this, and commercial fixtures are intended to handle that additional force without excessive flexing.

Anyway, today I made the two alignment posts from 1"-dia. steel and, after rigidly clamping the 1" plates together, drilled and reamed one of the three holes before quitting for the day. I'll use bushings in the holes accurately sized to the worn spindles. Also, this will let me use this same fixture in the future should I ever need it for a Gold Star crankshaft.
Posted By: koan58

Re: 1928 Ariel Model C - 12/27/17 1:52 am

I can see how such a jig would give you a good start with the assembly.
I can imagine others less thoughtful than yourself assuming that they can assemble a crank with such a tool.
At the end of the day, I'd be surprised if you didn't resort to the traditional whacking with a soft hammer while tightening the nuts to achieve the best compromise.
I suspect you would almost be reliving something done in 1927!
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/27/17 4:15 pm

Tracking of my "High" (i.e. closer ratio) gearbox that was shipped to me via myHermes International shows it will be delivered "no later than 04/01/2018." It also shows it arrived at their Hub somewhere in the UK on 22 December and then 8 hours later was "Misrouted to Incorrect Depot," with no further tracking information after that. So, following their instructions for what to do if tracking hasn't been updated for a few days, I contacted them via their 'live chat.' I was told that since it isn't Jan. 4 yet they don't consider the package lost (yet) so, while they have no information on where it is at the moment, I shouldn't worry. Oh well, at least it's insured.
Posted By: kommando

Re: 1928 Ariel Model C - 12/27/17 4:37 pm

Hermes do not have the best reputation so on the 5th I would be straight onto them unless its been updated, luckily our local Hermes driver is good so once they get themselves sorted in the hub we do not have to worry. You can relax a bit once its exited the UK.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/27/17 7:06 pm

Originally Posted by kommando
You can relax a bit once its exited the UK.
A month ago I was expecting a delivery from Amazon.com ("by 8pm") when a car pulled up around 8:15pm when it was dark, circled the driveway, then stopped maybe 150 ft. back down the driveway. I went outside and could see the driver looking at his iPhone in a way that appeared he was trying to figure out what to do. I walked over to him and he asked me where the front door was. I said he could just hand me the package but he said the app wouldn't let him mark the package as delivered unless he was within 50 ft. of the front door. Also a month ago UPS tracking site showed that a package to me had been misdirected to the east coast, after which I followed it as it made its way back across the country to be delivered. The point is, with current technology there's no excuse for Hermes not to know where a package is at all times, even if it's not where it's supposed to be.

Speaking of packages, 15 min. ago a Caswell Hard Chrome plating kit was delivered, complete with their 181-page manual. So, bearing and camshaft plating should happen within the next few days.


Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/28/17 10:59 pm

My younger, motorcyclist, daughter is in town for the week and we had hoped to take our traditional father/daughter ride for lunch in a mining town 100 miles from here, this year on Gold Stars. But she has to return to New York tomorrow, and visiting with relatives and friends this week didn't leave any time slots open that were long enough. Life is full of disappointments...

I didn't have a lot of time to work on the Ariel today (or any time this week, for that matter) but I copied the appropriate Cu plating section of the Caswell manual and highlighted the important points. I then laid out all the necessary chemicals, beakers and heater to be ready to plate, possibly tomorrow afternoon.

While doing some more machining on the crankshaft alignment fixture I calibrated the full range of the oven in the garage so in the future I would know where to set the dial to get the required temperature. In this case, the oven is needed for heating the bearing (and later the camshaft) after plating to remove the hydrogen. The oven takes ~15 min. to reach equilibrium at each new setting so I'd turn the dial to a new setting, machine for a while, then read the temperature when the light was cycling on and off indicating it had reached the new set point.

Another bit of progress today is that Hermes updated their tracking of my gearbox to "Receipt at Hub" from the previous "Misrouted to Incorrect Depot." So, there's hope they haven't permanently lost it. Yet.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/30/17 3:53 am

Hermes tracking shows the package went through several steps today, the last of which was "handed over to the Landmark depot." I found that Landmark is owned by the Belgian post office so I hope this doesn't mean the gears are taking an eastern route to me at the rate of a few hundred miles per week. At that rate it should be here in time to use in the 2020 Cannonball.

I finished the crankshaft alignment jig today and it came out great. However, whether or not it actually helps when it comes time to reassemble the crankshaft remains to be seen. I made it to very tight tolerances which I can see could be a problem unless I get the spindles accurately perpendicular to the flywheels prior to assembly, otherwise the shafts could bind in the jig.

Tracking Update: The gears have finally made it to Heathrow nine days after they were shipped from a village 125 miles away, for an average speed so far of 0.6 mph.
Posted By: RPM

Re: 1928 Ariel Model C - 12/31/17 2:31 pm

Happy New Year MM. Glad you are making some progress. Always seams to take longer than expected. Hurry up and wait.
I have made progress on the Nortons. We have the rolling chassis built for the 23 and 24. The 1924 had a crack in the steering head just behind the neck, rear wheel was tilted to the left by 9 degrees, Front end spindles would not rotate freely and front end had bent plates on both sides. The 1924 had 1/4" balls installed on the steering head instead of 5/16" balls. That did not work well. We never rode or heard bike run when we got it. It was put together and sold. Never started or ridden. Reminded me of something that would have come out of the Meacum Vegas auction. Looked nice but scary bad on the inside. Sun rims ,new spokes and sealed bearings in wheels are working great.
The 1923 was nice riding bike when we started in on it. Frame was nice and straight. Motor was a little tired but overall pretty good.
Trying to get everything going by April for a shake down run in the Texas Hill Country. Sounds easy but it won't be.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 12/31/17 4:52 pm

Originally Posted by RPM
Sounds easy but it won't be.
Now there's an understatement...

Originally Posted by RPM
The 1923 was nice riding bike when we started in on it.
I'm reminded of a conversation with my wife earlier this fall:

wife: What are you so busy doing in the garage?
me: I'm completely rebuilding the Ariel from the ground up.
wife: Why? It was running fine when you got it.

I trammed the mill to better than 0.0005" out of 13" to get ready to ream the small end bush, but then decided the lathe would be better. I used chaterlea25's favorite PB1 bronze to make a new bush, a boring bar to make the ID a bit smaller than the final size but perfectly parallel to the OD, and then reamed to the final 13/16" (0.8125"). After pressing it into place I reamed it again but found it a smidgen too tight with the old gudgeon pin. At that point I measured the ODs of the three pins and found: old one that was in Ariel 0.8112", Gardini 0.8115", and Omega 0.8122". I'll measure the actual ID of the bush today and, after making my final decision on the piston to use, I'll gently hit it with a hone to size it for the appropriate pin. I'll also measure the side-to-side tilt to confirm that it's well within the limits it needs to have.

As a check on the point koan58 asked about my earlier balance factor calculation I measured the weight of the bush I removed. It's 88.86 g. Rather than calculating the weight of an original 1" ID bush based on geometry and an assumed density of bronze, I took an experimental approach. I drilled it with a 1" bit and measured the weight again. It's 47.77 g, for a difference of 41.09 g in the weight of the small end of the gudgeon pin. This is different than my previous calculated weight so was well worth the time it took to determine this. Thanks, koan58, for your post that prompted me to do this.

Actually, the bush protruded from both sides of the rod so, assuming an original 1" bush would have been the width of the rod, it would have weighed slightly less. I trimmed the bush to the width and remeasured it at 40.65 g for a final-answer difference of 48.21 g. I'll use the 40.65 g value of the weight of an "original" 1" ID bush when I revisit the balance factor calculation.

Finally, KevinN must have received an email from the organizers I haven't seen yet because yesterday on his AMCA thread he was able to post a route map showing the locations (but not the still-secret names of the towns) of the evening stops. Participants were given the stops a few weeks ago but sworn to secrecy.

[Linked Image]
Posted By: koan58

Re: 1928 Ariel Model C - 12/31/17 8:11 pm

Hi MM,
Thanks for your thanks, I'm just glad that it was worthy of, rather than a waste of, your time.
Just by way of a footnote for purposes of comparison between real-world and calculation:-

Reducing bush actual = 88.86
calc = 89.40 (as a parallel tube, no tapers)

Original bush actual = 40.65
calc = 39.93

Considering the possible slight errors in density and dimensions, I think the correspondence is pleasing.

I look forward keenly to your electrolytic adventures!

Hoping the "laws of physics" continue to apply for you in 2018! Dave
Posted By: robcurrie

Re: 1928 Ariel Model C - 12/31/17 11:32 pm

The Cannonball organisers posted the map on their Farce Book page, their website doesn't seem to be working properly except for their merchandise section.
Rob C
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/01/18 5:15 pm

Originally Posted by koan58
Hi MM,Thanks for your thanks,
Credit where credit is due.

Originally Posted by koan58
for purposes of comparison between real-world and calculation...
This is a good opportunity to make a general point. For the record, (absent arithmetic error...) the level of agreement between estimate and calculation is as to be expected. When someone (not koan58) writes something like "in theory is should have been..." and then quotes a 'real world' result that differs all that means is they used the wrong theory (or made an arithmetic error...).

Originally Posted by Magnetoman
I measured the ODs of the three pins and found: old one that was in Ariel 0.8112", Gardini 0.8115", and Omega 0.8122". I'll measure the actual ID of the bush today
Setting the bore gage on the diameter of the smallest pin (0.8112") the ID of the bush is 0.0002" larger. This very tiny clearance was enough to allow the smallest pin to be a tight press fit, but the other pins are larger so I'll have to hone the bush for whichever of the two aftermarket pistons I decide to use.

With the bush in place it was time to address the slight bend in the connecting rod. As far as I could determine it was a simple bend originating at the big end and resulting in the small end being displaced sideways by 0.025". Since the small end is ~6.5" away from the point of the bend, and the gudgeon pin is ~2.6" wide, this resulted in one end of the pin being 2.6/6.5x.025 = ~0.010" higher than the other. The top of the piston is ~1.25" above the gudgeon pin so this would result in one side being 1.25/2.6x.01 = ~0.0048" closer to the cylinder wall than the other (similarly for the opposite skirt since it's roughly the same distance below the pin and the top land is above it). Given the piston/bore clearance, clearly this is a problem that has to be addressed.

It took repeated use of the press, precision 2"x4"x6" blocks, and test indicators to reduce the side-to-side tilt of the pin to 0.0018". The problem with doing better than this isn't with the measuring instruments, but with the reproducibility of mounting the rod in the blocks for measuring using the machined surfaces of the sides of the big end. My first project of the New Year will be to machine a mandrel to fit in the big end and use it to see if I can do a bit better. But, the 0.0018" tilt translates to just under 0.001" reduction in clearance to the bore at the top and skirt of the piston, which would be fine.
Posted By: Alan_nc

Re: 1928 Ariel Model C - 01/01/18 7:48 pm

Is there a way to calculate the rate of ware to the cylinder? In other words: at the end of 3,000 miles how wallowed out will the cylinder be. I know you are trying to minimize this but with whatever you do are you going to have an engine that self destructs at x miles. And....if this can be calculated is there a way to predict that x miles will be y miles past the completion point? Yea I know.........if pigs could fly
Posted By: robcurrie

Re: 1928 Ariel Model C - 01/02/18 12:27 am

I think it will be very difficult to calculate wear due to there being so many variables, you would do better to use historic data rather - but that may vary vastly because of factors like weather, geology of the area the engine is used in and rider, to mention a few. Also, 3000 miles is not very much for an engine like this, it would just be bedded in nicely!

Rob C
Posted By: kommando

Re: 1928 Ariel Model C - 01/02/18 8:49 am

Take a sample of used oil and send it away for analysis, after the 3rd oil change you will have an idea of the typical analysis of a normal contents, any subsequent analysis showing different results tells you something is up.
Posted By: Tridentman

Re: 1928 Ariel Model C - 01/02/18 2:12 pm

What Kommando describes is common practice on large (10000-15000 hp) diesel engines being used in ships or for land based power generation.
In the latter case the engines are run 24/7/365.
It is quite a sight to see the tappets being readjusted while the engine is running---the locknuts have a wrench about 3 feet long and it takes two guys to do it!
But--I digress---the oil analysis in these situations is used to schedule down time for bearing changes etc.
But to do so needs a lot of data gained over many years for it to be at all accurate.
Overall I would suggest that it is of dubious value in this case.
I tend to agree with Rob---this engine --due to the great attention to detail on the part of MMan, is going to be better than any Ariel engine that. ever left the factory.
And even factory or back street assembled engines in the day with poor or non existent maintenance, could swallow 3000 miles with little problem
Just my two centsworth of course.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/02/18 2:41 pm

Originally Posted by Alan_nc
Is there a way to calculate the rate of ware to the cylinder?
I doubt cylinder bore wear will be an issue. The exposed valve guides, on the other hand...

Yesterday ended with me 0.0010"-0.0015" closer to assembling the crankshaft. I machined a mandrel for the ~1.5" ID of the big end of the rod with a tight push fit, and with the ends of the mandrel parallel with each other to within 0.0001". Clamping one end of the mandrel with the rod against the side of a precision "cylindrical square" would make the top surface of the gudgeon pin perfectly parallel to the surface plate if the bend in the rod had been completely eliminated. A number of trips back and forth between the press and the surface plate got the gudgeon pin parallel to within 0.0010"-0.0015" (~0.0005" was the reproducibility of the measurements when I would unclamp the assembly, rotate the rod somewhat in the mandrel, re-clamp, and re-measure).

Key to doing this was having a way to reproducibly bend the rod, and to reproducibly measure the result. I used large C-clamps to hold the platform of the hydraulic press rigidly against the frame and used a dial indicator with magnetic base to determine the deflection of the rod. The big end of the rod was clamped between two 2"x4"x6" machinist blocks which in turn were held to the thick steel plates on the press's platform by large C-clamps. All of this was to remove as much extraneous free play as possible.

I would zero the gauge and then apply force in ever increasing increments, each time dropping back to zero force to read the indicator. The initial applications of smaller forces ensured play had been removed from the system, but at some point after deflection measured an inch or so from the small end had exceeded ~0.1" the indicator showed a permanent deflection had been introduced. Already from my most recent measurement on the surface plate, corrected for geometry, I knew how much deflection I needed so I would stop when that point was reached. However, working to 0.0001" with 8" C-clamps and a 30T hydraulic press has its limits so even when I was very close it still took a few more trips back and forth to achieve the final result.

Despite all of the above I'm not finished with the rod just yet. I let it soak in the oven at 150 oC for two hours last night and will remeasure it later today to make sure remnants of the bend haven't returned. I pulled that temperature out of the air; it's higher than the big end will reach in operation, which is where the bend was located, but lower than the small end. I'll also Magnaflux it again. Finally, when I assemble the crank I'll reuse the crankpin and bearing assembly that was in it since they show no sign of wear, leaving me with a new Alpha crankpin surplus to needs.

The ~0.025" bend in the rod that I just reduced to ~0.001" was in it when I removed it from the engine. That bend was large enough that it should have caused the old piston to contact the cylinder wall so I examined that piston again. Sure enough, there is obvious scuffing of the lower portion of the skirt on one side and the portion above the gudgeon pin on the other. The piston clearly had been well-worn when the previous rebuilder installed it, and I knew I would have to replace it, so I hadn't paid much attention to the specific marks until now. I'll speculate that the bend was introduced by someone who pressed or pounded the gudgeon pin (or bush) in or out at some time without supporting the piston/rod.


Attached picture IMG_6398.JPG
Attached picture IMG_6400.JPG
Posted By: Rich B

Re: 1928 Ariel Model C - 01/02/18 6:57 pm

Details on the stops for the Cannonball are being posted. My local AMCA chapter actually sent an email yesterday with the Ohio stops. Need to get my room reserved so MM & Kevin N have a pit monkey available. cool
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/03/18 12:58 am

Originally Posted by Rich B
Details on the stops for the Cannonball are being posted. My local AMCA chapter actually sent an email yesterday with the Ohio stops.
I smiled when I received the mail with the list of stops and read that all ~100 of us were supposed to treat the information as secret. Sure, with 100 people, like that's going to happen. However, I always keep information confidential until it is clear others have spilled the beans.

Originally Posted by Rich B
Need to get my room reserved so MM & Kevin N have a pit monkey available.
I hope to arrive each evening refreshed, full of energy, and able to socialize well into the evening because no maintenance will be needed on the Ariel for it to be ready for the next day. However, in the unlikely event it doesn't play out quite that way ...

By the time the trip starts in September it will have taken me over a year to prepare for it. And, even then, I won't know for sure when I'm on the starting line whether or not I'm actually fully prepared for what's in store. In contrast, more than once I've left on trips halfway around the world that I didn't even know about until the day before I bought the tickets and left. Traveling to Portland OR is way more complicated than traveling to Phnom Penh.

The heat treatment resulted in ~0.002" of the bend returning, i.e. ~10% of the original bend. So, today I overcorrected the bend by ~0.001" and subjected the rod to the same two hours at 150 oC. Following this I checked it and found the same value as before the heat treatment.

However, I then switched from using a 0.0001 dial test indicator (DTI) to a Mahr Millimess 50 millionths (half of a ten-thou.) dial indicator. I should have used it from the start. A DTI can be a bit more convenient for many measurements, but it's really only accurate for finding 0, and only roughly measures deviations from 0, while a dial indicator gives true readings. Further, Millimess gages have no detectable hysteresis so you can rely on their readings. Anyway, with the Millimess the gudgeon pin is 0.0014" higher at one end than at the other, consistent with the less accurate DTI measurement I made before baking the rod. Now, since I can rely on the measurements to better than 0.0001", this evening I put the rod back in the oven to cook for another two hours at 150 oC to be absolutely sure the rod doesn't have any inclination to rebend.

Interestingly, the heat treatment gave the PB1 bronze a slightly darker, slightly brownish hue that is close to the color of the bronze bush that had been in the rod when I got it.
Posted By: koan58

Re: 1928 Ariel Model C - 01/03/18 2:23 am

Hi MM, cracking stuff!

We went to Millimess all of a sudden, is that CMM or similar? What makes it inherently more accurate(without recalibrating?).

In metrology, I often found the shadowgraph very helpful, ok the precision a bit vague, yet when you're dealing with an object, it works quite well.

It surely is important that the bore and stroke is roughly in the right direction, that the finely crafted engine has it's angelic balance, and hopefully tows a few despondents over the finishing line.

I don't know what is allowed, but can you put a drip to your rockers? Dave
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/03/18 5:41 pm

Originally Posted by koan58
I don't know what is allowed, but can you put a drip to your rockers?
I addressed this in a previous post some time ago. The short answer is I don't intend to feed oil to the rockers or valve guides.

Originally Posted by Magnetoman
with the Millimess the gudgeon pin is 0.0014" higher at one end than at the other
It's now 0.0016", but I'm at the limit of measurement uncertainty so call the readings identical at 0.0015", i.e. last night's heating didn't change anything. However, the heating cycles have tightened up the ID of the bush by ~0.0001" (judged by the tighter feel of the pin) so it's good I went through this procedure prior to final honing to size.

The top lands of both aftermarket pistons are 1.25" above the center line of the gudgeon pin so the tilt will bring one side 0.0015" x 1.25"/2.5" = ~0.0008" closer to the cylinder wall than the other (unless combustion pressure equalizes the gap). If it's bored with a 0.005" clearance, i.e. 0.0025" per side, that's ~1/4 of the gap. Looked at differently, and again if combustion pressure didn't center the top of the piston in the bore, it would be as if one side had been bored with a 0.0066" clearance and the other with a 0.0034" clearance.

The skirt of the Gardini piston is 1.5" below the gudgeon pin so it would be a little closer, and a little further from the wall than the top. However, the Omega piston has a much shorter 0.7" skirt on the sides so there certainly wouldn't be clearance issues with it with the present slight bend.

I'll revisit my balance factor calculation to decide which piston to use which, in turn, will tell me by how much to hone the bush. The 0.0014"-0.0016" taper over the 2.5" length of the gudgeon pin corresponds to 0.0006" over the 0.997" width of the bush. I'll mount the rod horizontally on the mill using the mandrel I've been using for these measurements, which will make the small end precisely parallel to the big end. Honing for either piston's pin will remove at least three-quarters, if not more, of this material so there would be no point attempting to straighten the rod further before doing this (and, possibly no point in doing it after honing).


Gearbox update: Hermes tracking shows my gears arrived in the U.S. yesterday afternoon, in Buffalo, NY of all places.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/03/18 8:36 pm

Absent someone like koan58 finding an error in the following revised balance factor calculations it looks like the original balance factor was 65% and that the Gandini piston will be going in the Ariel:

-- revised ------
A formula for calculating the Balance Factor can be written in the form:

Balance Factor = balance weight + small end weight / piston weight + small end weight

As can be seen, to solve this requires determining three weights as well as having a fixture for holding the crankshaft so it can rotate freely when the balance weights are added.

Small end weight:
With the 13/16" bushing to reduce it for a smaller gudgeon pin than the original 1" pin it weighs 267.5 +/-1 g. However, from this subtract 48.2 g for the "excess" weight of the bronze in this smaller ID bushing so it originally would have weighed 219.3 +/-1 g.

-- Current small end weight = 267.5 +/-1 g
-- Original small end weight = 219.3 +/-1 g

Piston weight:
The "piston weight" is that of the complete assembly of piston, gudgeon pin, circlips and rings. Although it doesn't enter into the calculations shown here I'll note that the weight of the additional Al used in a, say, +30 piston is not negligible. It can be calculated from the annular volume of a piston of stock diameter and one 0.03" larger than that.

-- weight of +30 piston assembly that was currently in my bike 467.5 +/-0.5g

I was lucky to find two people with original piston assemblies for the Ariel. The one in Australia is used and weighs 507.2 g and the one in Canada is new and weighs 503.5 g.

-- weight of original piston assembly weight (average of above) = 505 +/-2 g
-- weight of aftermarket +60 Gandini piston assembly 516.5 +/-0.5 g
-- weight of aftermarket +60 Omega piston assembly 435.0 +/-0.5 g

Balance weight:
I hung balance weights and washers from a wire attached to the small end until the crankshaft was in balance and weighed the final total mass. It took 196.59 g plus 10 g on the rim at 90o. Taking into account the off-axis imbalance I estimate the uncertainty in balancing the crank using only weights hanging from the connecting rod and none at 90o is +/-3 g.

The weight of the heads of the two 1/4" cap screws pinning the big end is 2 x 2.74 grams = 5.48 g. Without the cap screws it would have required that much additional weight, plus the 48.2 g that the current bronze reducing bush weighs more than the original 1" bush. So, to originally balance the crank it would have required 196.6 + 5.5 + 48.2 = 250.3 g.

-- weight to balance crankshaft in its current form = 196.6 +/-0.1 g
-- weight to originally balance crankshaft = 250.3 +/-2 g

If the 5/16" holes were added sometime later the original weight required to balance it would have been 38.9 grams less.

-- weight to originally balance crankshaft without the four 5/16" holes =211.4 +/-3 g

Original factory balance factor:

If the crankshaft in its current form (less the cap screws) is how it left the factory, the original balance factor was:

250.3 + 219.3 / 505.0 + 219.3 = 469.6 / 724.3 = 64.8 +/-1%

If the four 5/16" holes were added later it would have required 38.9 grams less to balance it originally. In this case the original balance factor would have been

211.4 + 219.3 / 505 + 219.3 = 430.7 / 724.3 = 59.5 +/-1%

For comparison, a 1960 BSA Service Bulletin shows 60% for the 250cc 'C' series, 58% for Gold Stars, 55% for the essentially identical 'B' series singles in the same frame as the Gold Star, and 55% for both the 500cc and 650cc 'A' series twins, also in the same frame as the Gold Star. A 1930s Vincent Comet used 66% (claimed weight 390 lbs. vs. 290 for the Ariel) but this had to be reduced to 61% in a lightweight speedway frame.

Current Balance Factor:

With current piston in it:
196.6 + 267.5 / 467.5 + 267.5 = 464.1 / 735 = 63.1% +/-0.3%

If Gandini piston were used in it without any other changes:
196.6 + 267.5 / 516.5 + 267.5 = 464.1 / 784 = 59.2 +/-0.3%

If Omega piston were used in it without any other changes:
196.6 + 267.5 / 435.0 + 267.5 = 464.1 / 702.5 = 66.1 +/-0.3%

To reduce the balance factor to 65% if using the Omega piston would require reducing the required balance weight by 7.5 g which in turn would mean removing roughly half that weight from the rim of the flywheel. This could be achieved by, for example, drilling two additional 5/16" holes approx. 3/16" deep each. If I did this I would carefully and incrementally make any such changes only after assembling the flywheel and checking the balance.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/04/18 3:17 pm

Originally Posted by Magnetoman
... the ODs of the three pins ... old one that was in Ariel 0.8112", Gardini 0.8115", and Omega 0.8122".
Since it looks like I'll be using the Gardini I honed the bush for it. Should I change my mind the hole can be made larger for the Omega easier than it could be made smaller. Also, I fussed some more with the bend in the rod, finally getting it down to 0.0005" over the 2.5" of the gudgeon pin.

I couldn't find any specs on the allowable bend for connecting rods of any kind, let alone the one in a 1928 Ariel, but I did find that Sunnen sells a fixture(*) for measuring bends that certainly isn't any more precise than my setup. Their fixture includes a long steel bar for bending the rod into shape. I can't imagine a crowbar wielded by a mechanic being able to work to extraordinarily high precision, and in any case at the current level of tilt the results of each of my tweaks is more luck than it is skill.

The remaining 0.0005" of tilt I didn't remove (oh, the shame of it...) means the tops and bottoms of the piston will be 0.00025" nearer/farther from the bore than if there were no tilt at all. It's hard to imagine this will be a problem.

(*)TN-111 Rod Aligner. I found a pre-1960s Sunnen manual for this fixture on line that describes how to use light passing through a gap to determine if there is a bend and how to remove it, but it provides no specifications or indication of accuracy. However, my Brown & Sharpe cylindrical square is designed to measure tilt when it is in one orientation so it provides an answer to this. An object 2.5"-long falls between the 0.0006" and 0.0008" contours, i.e. this is the limit of the tilt you could hope to detect in a machine shop by looking at light in the gap between two straight edges. By this measure, if the Sunnen fixture was good enough for rebuilding engines back in the day, the tilt I achieved is at least 50% better than good enough.
[img]http://www.practicalmachinist.com/v...sharpe-master-cylindrical-square-299766/[/img]

Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/04/18 7:59 pm

Hi MM, interesting stuff and I am pretty sure that your rod is straighter than any out there.

Regarding the other jigs that you mention I agree with you that your method is more accurate.

Only a few days ago I read some articles posted by Cotten on Virtual Indian about crank rebuilding and balancing. On the page about "Inspection" I noted a couple of pictures, one showing a vintage Aamco rod alignment gauge and another showing a fixture being used in a press to straighten a rod. Obviously you have straightened yours but if you haven't seen them already then the pictures may be of interest. If you click on the thumbnails they get bigger.

link here: http://virtualindian.org/1techflywheel3.htm#straight

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/04/18 8:59 pm

Originally Posted by George Kaplan
I noted a couple of pictures, one showing a vintage Aamco rod alignment gauge and another showing a fixture being used in a press to straighten a rod.
Thanks very much for the link to that thread. That Aamco gauge is similar in principle to the Sunnen. The fixture for straightening rods is, ahem, a bit agricultural for my tastes.

My process for measuring, and removing, the bend was a case of me reinventing the wheel. Only last night, after having solved my own particular problem, did I think to use google. And then it was just to see if I could find a spec on the acceptable amount of bend. That's when I found the Sunnen fixture. Interestingly, I couldn't find very much at all about rod straightness on Britbike (which must mean everyone who rebuilds their engines simply knows their rods are straight...).

The late Pete R wrote about straightening rods that he liked to achieve 0.002" in 8" (equivalent to 0.00063" in 2.5"). Although he didn't mention how he decided on that figure, from the context it may be that this allows the rod to slip through both connecting rods in an assembled twin engine. His description relies on having an 8" rod that is known to be straight to within a few ten-thou. as well as a tight fit in the small end bush. Still, it's the identical procedure as the one I used, except I used a shorter rod (the gudgeon pin) in combination with a more sensitive gauge to make the same measurement.


Tracking Update: My gears were sighted in Buffalo NY on Tuesday, York PA on Wednesday, and Glendale Heights IL today, so they're coming across the U.S. on a Conestoga wagon rather than an airplane. However, the web site continues to maintain the fiction that "The delivery date of your parcel should be no later than 04/01/2018." Although, in the American way of writing dates, that's April Fools Day, so maybe it is correct.
Posted By: kommando

Re: 1928 Ariel Model C - 01/05/18 1:24 pm

Could be worse, what if it said 29/02/2018 !!!!
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/05/18 5:43 pm

Again, KevinN has the information on his AMCA thread from some source (Facebook?) other than the email from the organizer. Here are the towns where we'll be spending the nights:

Grand Departure, September 8: Portland, ME
Stage 1, September 8: Keene, NH
Stage 2, September 9: Binghampton, NY
Stage 3, September 10: Jamestown, NY
Stage 4, September 11: Bowling Green, OH
Stage 5, September 12: Bourbonnais, IL
Stage 6, September 13: Anamosa, IA
Stage 7, September 14: Spirit Lake, IA
Stage 8, September 15: Pierre, SD
Stage 9, September 16: Sturgis, SD
Rest Day, September 17: Sturgis, SD
Stage 10, September 18: Billings, MT
Stage 11, September 19, Great Falls, MT
Stage 12, September 20, Kalispell, MT
Stage 13, Septmeber 21, Spokane Valley, WA
Stage 14, September 22, The Dalles, OR
Stage 15, September 23, Portland, OR

A straight line between Anamosa and Spirt Lake comes close to the town where I was born so I assume the town fathers will start organizing a parade in my honor once word reaches them...

With the rod taken care of it's time to assemble the crank and see how much trouble truing the shafts will give me, and whether the truing jig was worth the effort it took to make it. I don't have much time today so starting on that probably will have to wait until tomorrow.
Posted By: old mule

Re: 1928 Ariel Model C - 01/05/18 8:43 pm

The old crank alignment article from the 40s by "Slide Rule" himself was reprinted on line today in the "OZ Vincent Review". A good reaad.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/05/18 9:48 pm

Originally Posted by old mule
The old crank alignment article from the 40s by "Slide Rule" himself was reprinted on line today in the "OZ Vincent Review". A good read.


Thanks old mule I found it on-line. Is "Slide Rule" Phil Irving? I ask because it looks like an extract from one of Phils books.

John


Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/05/18 10:05 pm

Originally Posted by George Kaplan
Is "Slide Rule" Phil Irving?
Phil Irving chose that as his nom de plume because at the time it signified the fact the writer was a skilled engineer. However, no one born since ~1960 would have even seen a slide rule in school which means none of the parents of current college students, let alone the students themselves, are old enough to have seen one in use. Now it would signify the fact the writer is from a lost era of obsolete technology. That said, I keep a Post Versalog on my desk for old times' sake. When the N. Koreans take out our power grid with a nuclear blast I'll still be able to compute the square root of pi (1.77) when everyone's PCs are dead.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/05/18 10:26 pm

Thanks for that MM. Also thanks for the explanation for those who dont know what a slide rule is.

My daughter and my nieces and nephews cant get their heads around the fact that when i took my high school maths and physics exams, calculators were banned and we had to use log tables and sin, cos and tan tables. They sort of get sin, cos and tan tables but have no idea what log tables are.

However we are in a different era and things move on. Not always for the best but they move on.

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/05/18 11:22 pm

I have a collection of once-essential, now-obsolete scientific tools that I drag out every year to astound the audience: slide rule (same 'Astrolog' model I got in high school), circular slide rule, TI-59 calculator with card reader, Gerber variable scale, zero setting compensating planimeter, proportional divider, log-log graph paper, Polaroid film (for oscilloscope and microscope cameras), articulating compass drafting set, Dietzgen Master Detailer aluminum drafting set, French curves, ships curves, railway curves, ellipsograph, and Leroy lettering set. Few in college have heard of any of these tools, and none have seen any of them in operation, yet as recently as ~1985 all of these tools (except slide rules) were widely used.

The planimeter almost always gets the greatest interest since its operation is so non-obvious, yet I show them how remarkably accurate it is. If you need to accurately know the area inside a BSA A10's timing cover gasket, a compensating planimeter is the tool for you.

Although I have a real fondness for old technology (hence the 1928 Ariel...), not for a moment would I want to trade a modern instrument for whatever in the above list it replaced.
Posted By: Rich B

Re: 1928 Ariel Model C - 01/06/18 12:35 am

I find obsolete technology to be fascinating!
Posted By: kevin roberts

Re: 1928 Ariel Model C - 01/06/18 12:42 am

at a swap meet once, i stood in front of an ancient bamboo-backed slide rule, beautiful with the original leather case. three dollars.

i didn't have three dollars.
Posted By: Stuart

Re: 1928 Ariel Model C - 01/06/18 4:42 pm

Originally Posted by George Kaplan
calculators were banned and we had to use log tables and sin, cos and tan tables. They sort of get sin, cos and tan tables but have no idea what log tables are.

And when you say something like, "it expands logarithmically", blank looks guaranteed ... laughing

The "Drafting sets" on the same page as the Leroy lettering sets were common when I was in school and college. However, here in GB, the British Thornton company then supplied drafting instruments individually through schools and colleges, and their then-innovative idea was to supply the cases simply lined with foam; the owner bought whatever instruments he (the gurls were doing cookery ...) desired; when the case was closed, the foam pressed on the instruments and kept them in place. Still got all mine, including a 10" beam compass/dividers and 10" extension ... I can still draw/scribe a 40"-diameter circle anytime ...
Posted By: Alan_nc

Re: 1928 Ariel Model C - 01/06/18 6:06 pm

I was in a 4 hour math final in college and a student ask the professor if we could use a calculator. He gave the student a funny look and said "go ahead if you want". I think everyone who had a calculator was finished with the exam in about 30 minutes. That was at Ohio State in 1963.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/06/18 6:32 pm

Originally Posted by Rich B
I find obsolete technology to be fascinating!
Enough discussion of obsolete technology, let's return to discussing the um, er, 1928 Ariel...

I have everything ready to try to hold the 32 rollers in place while I slip the connecting rod over them without having any roll under the workbench, and then press the crankshaft back together with my fixture and measure it to find the shafts parallel to within 0.0001"...

Meanwhile, to make sure I'm ready for the following step, I laid out everything for Cu plating the drive-side bearing: 9"-dia. plastic bucket (the Cu anodes need to be at least 3" and no more than 9" from the bearing), hot plate (plating solution at 110 oF), aquarium air pump (for agitation), and 1/2-Amp power supply (70 mA/in.2 x 5.89 in.2 = 0.41 A to plate at rate of 0.001"/60 min.). I also have a fish tank heater and will have to experiment with it and the hot plate to determine the settings needed to maintain the correct temperature.

Once I have everything in place I'll see if the kit supplied enough Cu sheet,when cut into ~1" strips, to completely surround the bearing (pi x 9" = ~28"). If not, I have OFHC Cu sheet to use to make up the difference.

All of the above might sound overly fussy, but electroplating requires the right parameters to produce a good coating. Presumably, Caswell has worked these out for their chemicals so I'll be following their instructions to the letter. After plating, the bearing will immediately go into the oven at 375 oF for 24 hours to eliminate the possibility of hydrogen embrittlement.


Tracking Update: 06/01/2018 - 09:53 Shipment received at originating postal facility
It doesn't indicate where that originating postal facility is located, but it must be very close indeed because it still shows that The delivery date of your parcel should be no later than 04/01/2018.
Posted By: kevin roberts

Re: 1928 Ariel Model C - 01/06/18 6:38 pm

lol, can't resist

i have some precision tools. back when i was a zoology student i spent $16 on a handful of stainless dissecting tools, and sewed a case for them. 45 years later i still have the kit, with stuff added. i can still skin out and stuff a museum-quality mouse in 15 minutes, start to finish.

[Linked Image]

butterfly forceps, alligator forceps, plain forceps, splinter forceps, blunt probes, needle probes, needles, handfuls of hemostats, operating scissors, iris scissors, metzenbaum scissors, scalpels with various blades, droppers, and so on. the complete skinning kit i a fishing tackle box includes vernier calipers, monel and brass tail wire, chatillion and pesola spring balances, skinning labels, india ink, rapidographs pens, a snake bite kit (never used . . .), hypodermic syringes and needles, and so on.

all my miniature vein and arterial clips were filched over the years by roommates searching for roach clips.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/06/18 9:57 pm

In the 1980s computer punch cards were still in use in some places, each 0.007" thick and storing 64 8-bit bytes. A 1 Tbyte hard drive is ~0.31" thick, and half the length of a card, so a stack of ~20 cards occupies roughly the same volume but the drive stores ~109 more data. My now-obsolete 160 GB iPod has 125 GB worth of music on it, 23,754 songs, in the same volume as a cassette tape that holds just 10 songs. This means that, if full, my iPod would store 3000x more songs in the same volume as a cassette tape. These orders-of-magnitude advances in electronics and magnetics were made in ~30 years.

Meanwhile, after 90 years of mechanical development the fastest production motorcycles in 2018 go only ~2x as fast as the fastest ones of 1928. As a result, someone who knew nothing about motorcycles would have no trouble recognizing that a 1928 Ariel and 2018 Honda were "the same," but couldn't possibly guess there is a functional connection between a vacuum tube and an IC.
Posted By: Triless

Re: 1928 Ariel Model C - 01/06/18 9:59 pm

That is really impressive, and interesting, Kevin. But I have simple springloaded devices that can stuff a mouse in a second.
The result is definitely not musuem quality, though.
Posted By: kevin roberts

Re: 1928 Ariel Model C - 01/06/18 10:38 pm

lol
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/08/18 3:21 pm

Good new on the gears. Tracking information dated the 6th, that only appeared on the site today, shows the package had made it as far as Las Vegas on Saturday and still will be delivered no later than last Thursday. All of this might be explained by the "Service Alert" that has been posted at the top of the web site ever since I first checked: "As a result of the adverse weather conditions experienced over the weekend and today, delays are expected in collections and deliveries." Aside from the permanently bad weather problems encountered by my package, should I ever need an organ transplant I'll encourage the hospital to use a different courier service to get the replacement to me.
Posted By: kommando

Re: 1928 Ariel Model C - 01/08/18 5:13 pm

Well now that Hermes UK are not really involved in this delivery anymore I can provide you with some light reading.

https://uk.trustpilot.com/review/my-hermes.co.uk
Posted By: Rich B

Re: 1928 Ariel Model C - 01/08/18 6:17 pm

John,

What is the problem here, this is the internet. Only those who have had bad service will post a review laughing
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/09/18 2:52 am

Originally Posted by kommando
Well now that Hermes UK are not really involved in this delivery anymore ...
Thank you for not sending that link earlier.

Originally Posted by Rich B
Only those who have had bad service will post a review
Only those with really bad service will post a review. And judging by the number of posts on that site, a lot of people have experienced really bad service.

I didn't want to jinx it by writing earlier, but a few hours after my previous post a flurry of updates showed the package actually was in my town and 'out for delivery.' Although it still shows as 'out for delivery,' it was dropped in my mailbox ~5 hours ago (no signature required). I suppose I can't complain about the total travel time (21 Dec. - today), but the incomplete and out of date tracking information infrequently posted was pretty frustrating.

In the package were six well-wrapped pieces that look to be well made. One shaft is inside the bushing of another and it rotates smoothly and with what feels to be the proper clearance, so it passes than indicator of quality. I'll measure the hardness, diameters, etc. later, when it's the gearbox's turn to be dealt with.

I couldn't stop myself from messing a little more with the bend in the rod. As a result it is now down to 0.00015" (+/-~0.00005") over 2.5", at which point I decided it was a waste of (more) time to try to do any better than that. I then Magnafluxed it again and started reassembling the crank.

I'm using the old crankpin and bearings because they look to be in excellent condition. If I replaced the pin assembly (pin, rollers, and outer race) I certainly would need to hone the race, as I would have to do with the current race even if I only used the Alpha crankpin and rollers. Anyway, if I could see anything wrong with the current crankpin assembly I wouldn't use it, but I don't, so I will.


Attached picture IMG_6651.JPG
Posted By: Stuart

Re: 1928 Ariel Model C - 01/09/18 7:44 am

Hi,

Originally Posted by Magnetoman
Only those with really bad service will post a review.

Without intending to hijack the thread, I've been a MyHermes user for at least five years and I've never received service even remotely as bad as claimed in the Trustpilot reviews. I'm a regular eBay seller and almost all my stuff goes by MyHermes (they can't do tyres or very high value stuff). Here in the Scottish Highlands, we suffer from some carriers loading their rates; organising MyHermes to pick up and deliver to me is just as easy and cheap as sending. Also here, I get the same guy picking up from me and delivering to me; thanks to the vagaries of the MyHermes computer system, he'll often pick up a day earlier than booked, MyHermes still deliver in the normal three days. :bigt

I haven't used MyHermes international delivery; aiui, it's fairly new, it's possible the tracking information part of their system needs reviewing and tweaking.

Regards,
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/09/18 5:40 pm

Given the sub-0.001" clearance I was sure the assembling the two rows of 16 rollers ea. onto the crankpin and then slipping the rod over them was going to be a nightmare, but it wasn't. To hold the flywheel on the bench while I worked on it I drilled 1" and 1-1/2" holes in a piece of 4"x4" wood to clear the spindle and nut on the crankpin and placed this on a towel to, I hoped, catch any wayward rollers. I then inserted the crankpin, gave it a light tap with a Cu hammer so seat it in the taper, and stuck the rollers on one-by-one using grease to hold them in place. Holding my breath I then slipped the rod over the rollers, but it only took gentle pressure and slightly wiggling and rocking to get it over both rows of rollers without dislodging any of them. After I had it together I used a pump-type oil can to force oil through the crankpin to wash away as much grease as possible since I don't know how much pressure the engine's lubrication system will apply to the oil.

Unfortunately, at that point I decided I no longer could ignore the fit of the spindles in the flywheels which results in neither of them being quite perpendicular. This has been nagging at me for several weeks, but when I tried to remove the Woodruff keys from the shafts so I could lap them into the tapers both keys were frozen. I then convinced myself the small tilt of each shaft with respect to its flywheel was acceptable. However, since a "blueprint" is only as good as the weakest link (or something like that), I have to deal with this.

Doing the right thing at this point and machining the frozen keys from the shafts I'll only have wasted the 15 min. it took to assemble the rod on the crankpin (assuming I don't lose any rollers when I take it off again...). If I wait until I assemble and true -- or try to true -- the crankshaft before I then do the right thing I'll have wasted hours.

A few notes: The cams have base circles of 1.478" and 1.483" so I suspect they were reground at some point to remove ~0.020" of wear marks, grooves, and roughness. The lobes measured from the base circle are 1.835" and 1.841", respectively. Interestingly, the cam for the oil pump, which is part of the single 4.4"-long camshaft along with both the inlet and exhaust cams, is a simple circle of diameter 1.070". It gets its cam action by being offset by 0.175" from the axis of the spindle.


Attached picture IMG_6356.JPG
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Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/11/18 4:17 am

I don't remember having described the oiling system before. A single-acting plunger pump operates from one of the three cams on the, um, camshaft. The other two being the inlet and exhaust. Oil is forced through a hole that runs alongside the timing side shaft of the crankshaft into a shallow hollow cavity on the side of the flywheel. Shims ensure a small clearance between the outer rim of this hollow and the case to keep most of the oil from escaping that way. Centripetal force flings the oil to the outer rim of the cavity where a 1/8"-dia. hole drilled at an angle channels it through the flywheel to a similar hollow at the crankpin. The OD of the cavity is 1.39" and the OD of a ridge at the end of the crankpin is 1.20", resulting in an annular area of thickness 0.19" between the cavity and the ends of the rollers. This is how the oil gets to the rollers.

The oil leaves the crankpin via one of two routes. One is simply out the other end and through the small gap between it and the flywheel. The other is through two small holes under the rollers that lead to a hollow drilled halfway through the crankpin (i.e. it is hollow at one end and solid at the other), and from there out the end of the crankpin to the cylinder wall on that side of the piston. However, unlike the crankpin that came in my Ariel the Alpha crankpin (which was used in other Ariel engines as well as mine) has a hole completely through it that is plugged at both ends by small hex screws, so it's not clear if the second oil escape route is important for my engine. Or, toward which side of the engine it should point if it is important. For what it's worth, the previous rebuilder aimed the outlet hole of the crankpin toward the timing side.

When stopped for any length of time, like getting fuel, and depending on the orientation of the flywheel when this happens, there is nothing to stop oil from draining back down the 1/8" hole and past the small gap into the crankcase, or out through the small gap at the crankpin and into the crankcase. So, even after a stop of only a few minutes it will be important to sit with the engine idling for a minute or two to give time for the juices to be flowing.

OK, back to the problem at hand. Before assembling the crankshaft I want to lap the spindles into their respective flywheel tapers since neither spindle is perfectly orthogonal to its flywheel. But, the Woodruff keys are frozen in place. I mean really frozen. When I clamp the exposed parts of the keys in a vise the metal clamped by the jaws lets go before the keys move, and if I try to lift them out with a screwdriver driven by a hammer nothing moves. It's almost as if they are silver soldered in place... say, wait a minute, maybe they were soldered in place to repair damaged keyseats in the shafts. Inspection at 60x shows a thin line of slightly golden, silver-solder colored, material between the key and the slot.

The problem now has two parts, the first being how to mount the spindles on the mill so their keyseats are parallel to the mill bed as well as with their sides precisely in the plane of the bed in order to let me cut the present key out. Mounting a shaft parallel to the bed is no big deal, but getting the surfaces of the present Woodruff key parallel to the bed is. Imagine mounting the shaft horizontal but so the key were at the 5:00 position instead of either 3:00 or 9:00. That would be easy to see and correct. How about 3:30? Still easy. However, "eyeballing it" to better than a few degrees isn't possible.

My solution was to mount the spindle in a 5C collet in a fixture. That took care of making the spindle parallel to the mill bed. Gage blocks slipped between the bed and the bottom of the spindle determined that height, so adding half the diameter of the shaft (1" for one, and 7/8" for the other), minus half the thickness of the 3/16" key, determines the height of the bottom of the key when it is in the correct horizontal orientation. That is, assuming the key is in perfect condition, which neither is, so there's a bit of uncertainty. In the case of the key in the 1" shaft it is 0.015" narrower than 3/16" over a portion so half of that has to be added to the mix. Rotating the spindle in the collet until the key hits a "stop" of the correct height sets the proper orientation for it to be ready for machining.

As for the depth, Machinery's Handbook has the answer. A 3/16x3/4 Woodruff key needs its keyseat to be 0.214" deep. So, tomorrow I need to bring the cutter against the shaft, set '0' on the DRO, back off and rotate the spindle against the "stop" to set the orientation, and then simultaneously mill away the current key and form a new slot to a depth of 0.214".
Posted By: quinten

Re: 1928 Ariel Model C - 01/11/18 8:22 am


orthogonal... sure why not

... as a simple process , if the key is suspected of being soldered , why not try de-soldering it ?

.



.
Posted By: kommando

Re: 1928 Ariel Model C - 01/11/18 11:33 am

Quote
if the key is suspected of being soldered , why not try de-soldering it ?


It's highly likely the soldering is to recover worn broken key slots, that the current key cannot be removed says its a good repair structurally but not necessarily dimensionally. by desoldering you are back to having to repair whatever you uncover. Better to make a fresh cut taking the current key out and leaving a proper cut key slot in its place which will be both structurally and dimensionally correct. The worst that can happen is a cut into both steel and braze/solder results in a tear at some point due to the differing requirements of cutting angles between the 2 metals. Then its back to desoldering.
Posted By: koan58

Re: 1928 Ariel Model C - 01/11/18 2:22 pm

I'm only throwing ideas out, with no experience of what you're trying to do.

If both keys are frozen in place, is it likely that both have been soldered in place? If so, I'd have thought that indicative of a radical crank failure, if the soldering is to fill damaged key slots. Are the flywheel slots showing any sign of damage?
If the crank had become sufficiently loose, wouldn't the tapers be wrecked?
With these old taper-fit cranks, wasn't it the idea to finally knock or press the components into "precise" alignment?
Whether the flywheel is orthogonal to the shaft to the Nth second of degree is surely unimportant?
Isn't the important thing that the 2 mainshafts and the crankpin are precisely parallel?

If the flywheels precess minutely, is that important? I'd suggest that if you think it is, then you should also individually balance the flywheels.

I think that you are making unnecessary work for yourself, by machining out the key slots. It sounds like they are very happy where they are, and if their external bits are sound, what improvement are you likely to achieve?

Your description of the oiling system is fascinating.

The offset circular cam - the Triumph pump is effectively the same.

The oiling priorities can be clearly seen (I assume you meant a slot in the mainshaft bush?) deals with that vulnerable area first. I think we'd usually expect a high pressure supply here nowadays, but I suppose things hadn't come that far from drip-feed, and the pump is probably more about flow than pressure? Anyway, this bush is the only bearing that needs continuous positive oilfeed.

Then the use of centripetal force (pretty small at the crank axis increasing greatly towards the crankpin, drawing the oil from the hollow in the flywheel.

I would then assume that the bigend bearing would be as full of oil as the pump supply would allow. Oil spraying from both sides of the rod supplying the piston/bore.

I'd see the only neglected bearing to be the driveside main, so my instinct would be to put the open end of the crankpin in that direction, as there will be some pumping effect from the bigend rollers through the drilling in the crankpin.

With regard to the issue of draining the sump every so often, I don't know what mods you're allowed, but if you could allow more oil throughput you may increase your chances of success.

Dave
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/11/18 4:57 pm

Originally Posted by kommando
Better to make a fresh cut taking the current key out and leaving a proper cut key slot in its place which will be both structurally and dimensionally correct
+1. In addition, heat causes warping, which is a very good reason to avoid it if possible. The problem with the non-orthogonality of the shafts may well be due to the soldering. The taper is ~10o (~5o per side) so whether or not it can be fully corrected by lapping without the spindle moving too much into the flywheel remains to be seen. If it does move too much, hard chrome plating and grinding, or machining a new shaft, are possible solutions, although I hope it doesn't come to that.

Originally Posted by koan58
Whether the flywheel is orthogonal to the shaft to the Nth second of degree is surely unimportant?
Isn't the important thing that the 2 mainshafts and the crankpin are precisely parallel?
It sounds like they are very happy where they are, and if their external bits are sound, what improvement are you likely to achieve?
It's not the Nth I'm worried about, it's N-8. As I discussed in a previous post the TIR of the crankshaft was ~0.008" when I removed it from the engine, which is ~8x larger than permissible.

If you think about it, getting the two mainshaft spindles and the crankpin all to be precisely parallel (as well as the shafts coaxial) when neither shaft is perpendicular to its flywheel is a losing battle with geometry. Only by knocking each of the three shafts out of ideal alignment with the four tapers might it be possible to get somewhat close (say, within 0.008"). The reason I will be cutting the keys from the shafts isn't because I'm trying for perfection, it's because I need to achieve good enough.

Originally Posted by koan58
(I assume you meant a slot in the mainshaft bush?)
Actually, no, although there is a slot in the mainshaft bush that is currently in the bike. An oilway in the timing cover casting exits into the case and flywheel cavity at the OD of the mainshaft bush. The bush currently in the engine has a linear groove at the top that feeds from the always-full timing chest. Although there is a breather in the timing chest that exhausts to a tube that drips oil on the chain, apparently the two flapper valves on the crankcase that bring oil mist into the timing cover keep the pressure in the chest higher than in the crankcase so oil is pushed along that groove in the mainshaft bush from the chest into the crankcase.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/11/18 5:37 pm

Originally Posted by koan58
Isn't the important thing that the 2 mainshafts and the crankpin are precisely parallel?
Dave



Yes but also both mainshafts have to be on the same axis, If you just go for parallel irrespective of how perpendicular the shafts are to the flywheels then you would lose the battle.


Originally Posted by Magnetoman
If you think about it, getting the two mainshafts and the crankpin all to be precisely parallel when neither crankpin is perpendicular to its flywheel is a losing battle with geometry.


Not that I have done this either but I am pretty good at basic geometry.

John
Posted By: chaterlea25

Re: 1928 Ariel Model C - 01/11/18 8:36 pm

Hi MM and All,
Quote
from there out the end of the crankpin to the cylinder wall on that side of the piston. However, unlike the crankpin that came in my Ariel the Alpha crankpin (which was used in other Ariel engines as well as mine) has a hole completely through it that is plugged at both ends by small hex screws, so it's not clear if the second oil escape route is important for my engine. Or, toward which side of the engine it should point if it is important. For what it's worth, the previous rebuilder aimed the outlet hole of the crankpin toward the timing side.


???????
The crankpin rotates within the crankcase and does not go near the cylinder or piston (usually?)
If oil escapes from the crankpin end then in my opinion that oil has missed the most vital bearing in the engine !! The Big End
Oil escaping from the sides of the big end will be thrown towards the underside of the piston and small end during the period
before and after TDC
This will be enough to lube the small end and as the new piston has an oil ring and holes/grooves through the piston wall
oil will find its way to the upper bore
The flywheel rims also dip into the oil in the crankcase and distribute this radially around the case, reaching the bore as well.
Oil will drain down the crankcase wall and lube the main bearings, which in reality only need a mist

I would leave the crankpin ends plugged,
The Ariel lube system is similar to period J.A.P engines, some have solid pins where the oil is just fed into one end of the big end bearing,
via a hole in the flywheel adjacent to the crankpin
On hollow pin engines the oil is fed through the pin as in most later design engines

I have experience of several different make 20's engines where the total loss lube system just drips oil into the crankcase
and leaves the rest to the splash effect of the flywheels
The big end life on these engines does not seem much shorter than positively lubed big end bearings (to a degree depending on design and use)
The small number of large diamater rollers used in Blackburne engines is not one of the cleverest, especially if the engine is used hard
I have converted my Blackburne engine so the total loss oil is directly fed to the big end via drilled mainshaft flywheel and crankpin
20's Rudge engines use a wide big end of "small" diamater with small diamater long rollers, no method other than splash lube is employed
but the big end bearings are very reliable

Lapping the mainshafts into the flywheels needs ultra care ,
The sharp ends of the tapered shafts will leave a ridge in the tapered bore in the flywheels
In order to get the shafts to seat in the reground tapers the ridge must be removed or the ends of the shafts relieved to clear the ridge
Blueing and scraping the tapers is my preference

John



Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/11/18 9:16 pm

Originally Posted by chaterlea25
The crankpin rotates within the crankcase and does not go near the cylinder or piston (usually?)
Er, um, blame this on a temporary mental swapping of big and small ends...

Thanks very much for your insights and inputs into this.
Originally Posted by chaterlea25
I would leave the crankpin ends plugged,
The crankpin I will be reusing has one end open with two small holes in the middle under the rollers. However, I doubt if much oil will leave via that route since the area of those holes is much less than the area bringing oil into the big end so most oil will flow on through to the other end of the crankpin.

Originally Posted by chaterlea25
Lapping the mainshafts into the flywheels needs ultra care , ... Blueing and scraping the tapers is my preference
Duly noted. My plan, subject to you pointing out fatal flaws in it, is to blue both the flywheel and spindle tapers, mount the spindle in a Z collet (7/8" or 1", as appropriate) on the mill, and with a dab of grinding paste lightly touch down in the flywheel taper to reveal the scope of the problem. Depending on what I find I'll either use a scraper to start working on the high areas, repeating as required with more bluing, or use the scraper to slit my wrists.


Posted By: chaterlea25

Re: 1928 Ariel Model C - 01/11/18 9:27 pm

Hi MM
Quote
The crankpin I will be reusing has one end open with two small holes in the middle under the rollers. However, I doubt if much oil will leave via that route since the area of those holes is much less than the area bringing oil into the big end so most oil will flow on through to the other end of the crankpin.


Ok slight misreading on my part
In that case I would plug the open end of the crankpin that you are going to use, to "force" all the oil to the rollers

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/11/18 11:53 pm

Originally Posted by chaterlea25
I would plug the open end of the crankpin that you are going to use, to "force" all the oil to the rollers
Will do. Upon close inspection when I got home this evening I found the open end is countersunk for a short distance but then tapped 1/4-26 for a distance before continuing on further into the crankpin. I'll make a custom fastener to fill as much of the volume as possible to minimize the number of mg of oil that can enter and totally disrupt the balance factor after it's set.
Posted By: robcurrie

Re: 1928 Ariel Model C - 01/12/18 3:00 am

Originally Posted by Magnetoman
Depending on what I find I'll either use a scraper to start working on the high areas, repeating as required with more bluing, or use the scraper to slit my wrists.

The profile of a scraper in not conducive to slitting wrists.

Rob C
Posted By: Tridentman

Re: 1928 Ariel Model C - 01/13/18 1:08 am

MMan--suicide is permissible during the Cannonball Run --but not during the preparations!
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/13/18 4:36 am

I made good progress today so the scraper hasn't touched anything organic. But, there's still plenty of time...

Following chaterlea25's advice to plug the open end of the crankpin I machined a 2" 1/4-26 cap screw to do the job. The hole in the crankpin starts with a 60o taper, followed by ~3/4" of thread, followed by a 3/16" hole to a total depth of 2". So, I trimmed the head of the cap screw at 60o to fit the taper and reduced much of the length to 3/16" dia. to fill the hole. This left 3/4" of hollow which, when it fills with oil after I balance the engine, will upset things by approximately 0.4 grams. Oh well, I'll have to accept this error. I briefly considered machining an extension to solder on but decided to spend the time on something else instead. I cleaned the threads thoroughly and used red Loctite.

Next was to remove the Woodruff key from the drive-side spindle. Following the procedure I mentioned in a previous post I moved the cutter against the edge of the spindle to set the '0' of the DRO then used gauge blocks to make the old key parallel to the mill bed. I then lowered the cutter to the top of the same blocks, then dropped it another 0.008" to adjust for the difference in height of the worn key. A few minutes later I had milled the new 3/16"x3/4" keyseat. Without a DRO and calculator (to add/subtract the various gauge blocks and other dimensions) it would have taken a lot longer. When done I found a 0.005" strip of metal at the bottom so my keyseat was that much shallower than the one from the factory (I removed the strip so now it's the same).

I'll have to be even more careful on the timing side. A few thou. doesn't sound like much but if I'm off by 0.005" sideways (not in depth, which isn't that critical) that will change the valve timing by 1/2 x 0.005" x 360o/(3.14159 x 7/8") = 0.32o. While not huge, it isn't 0, either.

Tomorrow the bluing goes on to see how the tapers mate.


p.s. the Cannonball web site is finally working:

http://motorcyclecannonball.com/




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Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/14/18 1:02 am

It turns out that the devil is in the..., well, Woodruff key. Which is, after all, a detail.

Today I mounted the now-keyless drive-side spindle in a 1" Z collet with the flywheel on the mill's table below it, brought the spindle down to center the flywheel and then clamped the flywheel in place. I then raised the spindle and coated the mating tapers with engineer's blue.

After it dried I inserted the spindle in the flywheel, removed it, and looked for high and low spots. However, as far as I could tell, there were no high and low spots. So, I removed both pieces from the mill and tapped the spindle into place, still without a key, and checked the runout of the rim of the flywheel between centers. Within the several thou. roughness of the flywheel the runout was no more than 0.002".

I then took used abrasive paper to remove ~0.001" from a new Woodruff key to make it a tight, but sliding fit in the slot in the flywheel, and then removed about twice that from the lower portion to make it a snug, but not too tight, fit in the spindle. The depth of the slot in the flywheel was 0.100" (specs. call for it to be 0.100"), but after pressing the key into the spindle it projected above the shaft by 0.110" even though I had cut the keyseat to the specified depth of 0.214". That clearly would be a problem even without looking at the spec, which calls for the key to project above the shaft by 0.094". So, I filed it down to the required dimension.

In light of the previous paragraph, plus the excessive runout when I first removed the crankshaft it from the engine, I speculate that the Woodruff key that was in the drive side projected by too much, forcing the shaft to be tilted. Unfortunately, I hadn't thought to measure the height of the cheap, disposable key before I cut it away so I can't know for sure. But, circumstantial evidence strongly suggests the Woodruff key was the cause of the problem on the drive side. The devil truly is in the details, and the fit of even something as insignificant as a Woodruff key can't be taken for granted.

The TIR of the timing side always was much better so instead of removing its spindle again I decided to press the crank together. Whether it was the assembly jig I had made, or beginner's luck, or both, straight from the press the TIR of the timing side was 0.003" and of the drive side was 0.004" when turned between centers and measured next to the respective flywheels. Although I pressed the crank together I didn't use full force, nor have I torqued the bolts yet. This is to allow some ability to tweak the alignment.

Both shafts have their high and low points in the same orientation indicating that one or both flywheels isn't perfectly straight on the crankpin. So, I used a C-clamp to squeeze the flywheel rims at the orientation where the shafts are at their highest excursion from straight. The TIR of both shafts measured next to the flywheels dropped to 0.002". I had to quit for the day at that point, but in light of these results I'm (over)confident that I can get the TIR to below 0.001" tomorrow. Of course, that may just be the margarita I had at dinner talking...
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/15/18 12:57 am

I sneaked up on the max torque I could apply to the crankpin nuts with a 3/4" breaker bar and large ring spanner (more than 150 ft.lbs. but less than 200), checking the runout as I went. Between centers I ended up with just under 0.003" TIR next to the flywheel at the drive side and just under 0.0005" (a half.thou.) on the timing side). In a previous post I found the timing side center was accurately drilled but the drive side center was off by 0.001" so it would have a TIR of 0.002" even if both spindles of the crankshaft were perfectly coaxial. Correcting for this, the actual TIR of the drive side is 0.001" and the timing side is 0.0005".

This measurement pushes the limits I can trust for the locations of the centers so I then moved it to my rollers. Instead of holding the crankshaft at the ends of the shafts, rollers support it on the shafts themselves fairly close to the flywheels. Because of the way it is supported the runout near the flywheels is "forced" to be zero there so any deviations from being coaxial, or if the shafts are bent, will be in the form of TIR of the ends of the shafts. Unfortunately, the drive-side end consists of splines that have suffered from wear and rust so the TIR measured there isn't too meaningful. The timing end has a taper and the crankshaft "walks" sideways slowly as it is rotated on the rollers causing the indicator to slowly move up or down the taper. Because of this it isn't possible to get a precise measurement of the TIR. However, it is no more than ~0.001".

The above means I've reached my goal of truing the flywheel to within 0.001". This also means I can line bore the timing side bush with respect to the drive side bearing and the 0.002" clearance of the bush will be sufficient to keep that end of the crankshaft supported on a cushion of oil without the shaft wearing into the bush.

The minimum side clearance of the connecting rod should be 0.006"-0.012" so I had a moment of real disappointment when a 0.006" feeler gauge wouldn't fit, until I found it was stuck to the neighboring 0.007" leaf. The clearance turned out to be 0.008" (min. clearance on one side as well as side-to-side movement).

The time I spent making the crankshaft alignment jig probably wasn't break-even on the time it saved truing this one, although I now have it for any future crankshafts and it will more than pay for itself on the next one. But, even for this one, having done an initial test fitting and knowing the jig easily got the alignment to within a few thou. meant I had no hesitation assembling, testing, and disassembling several times as I felt my way through the process of accurately truing a crankshaft.

With the crankshaft done this young man's fancy now lightly turns to thoughts of electroplating. Once I get the drive-side bearing plated and installed in the case I can slowly start putting the engine back together again. Unless it's Humpty Ariel...



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Posted By: chaterlea25

Re: 1928 Ariel Model C - 01/15/18 8:22 pm

Hi MM,
I'm glad to hear that the crank is back together !!!
"Tuning for Speed" suggests turning up a tight fitting collar to fit tightly on the splined shaft so that it can be indicated
I usually sit two ball bearings on the mainshafts and those in V blocks, adjusting the blocks so the shafts are level if there are different size main shafts and sit the lot on the mill table
Rotating the crank like this run out is easy to check and not dependant on centres
Place the bearings as near the flywheels as possible and check the outer ends
Then move the bearing out along the drive side shaft and check near the flywheel

I am not sure why you made a complicated plug for the big end pin?
The pin will never be filled with oil on a total loss engine, so the weight of the oil volume/ /balance issue does not matter
in my opinion

Keep up the good work
John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/15/18 11:42 pm

Originally Posted by chaterlea25
"Tuning for Speed" suggests turning up a tight fitting collar to fit tightly on the splined shaft so that it can be indicated
I considered doing that, and still may since I'm not quite done with the crankshaft yet. I still have to balance it in its present form once I make my final decision on which piston to use, and also to eliminate the ~10 g imbalance I found at 90o when I checked it in its original form. However, the measurements I made convinced me that I have the crankshaft trued about as well as is going to be possible, and within the 0.001" TIR that was my goal.

I have no experience with truing old cranks (although I've interacted with a few on Britbike... but, I digress), but going by Radco's description, when held between centers a "True Assembly" has no more than +/-0.0015" runout at the drive end (i.e. 0.003" TIR) and +/-0.001" (0.002" TIR) at the timing end. My crank is now trued to ~3-4x better than this which is why I'm prepared to declare victory and move on.

Originally Posted by chaterlea25
I am not sure why you made a complicated plug for the big end pin?
The pin will never be filled with oil on a total loss engine, so the weight of the oil volume/ /balance issue does not matter
I plugged it because:
Originally Posted by chaterlea25
I would plug the open end of the crankpin that you are going to use, to "force" all the oil to the rollers
Actually, when plugged it will be filled with oil because there are two small holes in the middle of it that are there to force oil to the rollers when the same pin is used in later engines with pressurized lubrication systems. Alpha lists the same A5 crankpin that they supply for mine also for other Ariel engines through 1953).

If the end of the crankpin is plugged it allows for the possibility of it filling with oil through those holes. If it does fill, the extra weight of the oil will alter the balance factor, albeit by a very small amount. Since I was going to plug it anyway, as per your suggestion, I filled as much of the volume as possible with the plug I made for it. Now if the remaining volume fills with oil that will be just 0.4 grams to upset the balance.
Posted By: chaterlea25

Re: 1928 Ariel Model C - 01/16/18 7:34 pm

Hi MM,
I must have misread or not "taken in" the route the the oil takes from the flywheel groove to the big end
I thought that the oilway through the flywheel lined up with the oilway into the crankpin (mid taper) as on later Ariel's & BSA's
and from there to the two holes that feed the rollers (provided the crankpin end plugs are fitted)

John

Posted By: koan58

Re: 1928 Ariel Model C - 01/16/18 10:06 pm

As MM described it a post or so ago, the lube system is "eccentric" almost literally, using centripetal chambers as stepping stones to the bigend bearings.
I'm not clear exactly how the timing side bush is lubed, is it just by immersion?
And the drive side bearing, is the little fling from the big end enough? That's why I thought maybe an open end to the crank pin may assist. The rollers would tend to pump oil into the pin, and hence to it's end? Only a thought.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/17/18 1:18 am

Originally Posted by chaterlea25
I thought that the oilway through the flywheel lined up...
I knew the total loss system didn't "need" the plug you asked for in a pin that had been made so it would cover a range of models, but mine was not to reason why, but to do and, well, make a plug and trust the Loctite to keep it in so the engine wouldn't die.

Originally Posted by koan58
I'm not clear exactly how the timing side bush is lubed, is it just by immersion?
And the drive side bearing, is the little fling from the big end enough.
Ariel's description is that after the oil makes it through the big end "it is thrown on to the piston and cylinder wall, from which it drains back to the bottom of the crankcase, where it is picked up by the flywheels and re-distributed by splash." That splashing is what lubricates the drive-side bearing.

The "oil-laden air" that is splashing around the crankcase gets driven into the timing case by two one-way valves. Once it fills the case to a predetermined level it drains through a small hole back into the crankcase to keep plenty there to splash around. The crankcase itself has a breather to the outside that is at the height of the bearing, but it's hard to believe oil gets that high because it would cause quite a drag on the flywheels if it did.

The level in the timing case is such that "the timing pinion is constantly running in oil." The timing pinion is above the crankshaft so the bush at the timing end of the crank is lubricated by immersion. The bush in it now has a long slot at the top (0.046"x0.046"x1.9"), which is 0.65" below the "official" drain hole of 0.086"-dia. Although the area of the slot is only 29% of that of the hole, and the slot is longer, which also would slow the flow, it still represents a drainage path into the crankcase so it could cause the level to be too low in the timing chest. Even if the flow into the timing chest is faster than that out through the slotted bush so it would fill to the proper level in steady state, it will drain down to that level when the engine is stopped overnight. I'll have to give some thought to this when I make a new bush.

The oil in the engine and timing case is supposed to be drained every 1000 miles and the timing case refilled with 1/4 pint. After doing this you turn the oil flow valve fully on, take several big puffs from your asthma inhaler, and run the engine gently until you no longer can see anyone standing next to you and all mosquitoes within 1000 ft. are dead. Then turn the oil valve back to its normal position and start off, knowing you have fresh oil and that the planet now will be 0.1 degree warmer than it was.
Posted By: gavin eisler

Re: 1928 Ariel Model C - 01/19/18 2:23 am

MM , luvvin it so far, the crank is 8 times better, great !, glad it was just the key. Fitting keys correctly is 2nd year apprentice stuff, you were very right to go through this motor, I reckon it will run like a sweetie, bad crank and twisted rod wouldnt have got too far.

,One thing that got a lot better after the 30s was exhaust valves, got any special plans there? Have you considered staged drops of castrol R , smell is a huge advantage.
Posted By: BSA_WM20

Re: 1928 Ariel Model C - 01/19/18 1:16 pm

Originally Posted by Stuart
Hi,

Originally Posted by Magnetoman
Only those with really bad service will post a review.

Without intending to hijack the thread, I've been a MyHermes user for at least five years and I've never received service even remotely as bad as claimed in the Trustpilot reviews. I'm a regular eBay seller and almost all my stuff goes by MyHermes (they can't do tyres or very high value stuff). Here in the Scottish Highlands, we suffer from some carriers loading their rates; organising MyHermes to pick up and deliver to me is just as easy and cheap as sending. Also here, I get the same guy picking up from me and delivering to me; thanks to the vagaries of the MyHermes computer system, he'll often pick up a day earlier than booked, MyHermes still deliver in the normal three days. :bigt

I haven't used MyHermes international delivery; aiui, it's fairly new, it's possible the tracking information part of their system needs reviewing and tweaking.

Regards,


And not meaning to cause the thread to drift even further off line.
The problem with transport is it is labour intensive so to do it properly cost a lot more money that few are willing to pay.
To be done economically requires a lot of consolidation then reconsolidating so it is always travelling with a lot of other parcels going sort of the same way which is what Hermes are doing.
As for the problems on the web site, that is arrogance & greed of owners.
The same advances that puts a life time of music on MM's iPod allows owners to equip drivers with all sorts of electronic gadetery that prevents the driver thinking let alone taking any sort of initiative .
Because the electronic system is so good & has taken all of the thought out of the job, the owners can then employ the brain dead and pay them less than unemployment benefits which is what is happening.

Evilpay has this down to an art.
I have bought 6 BSA catalogues the past year and all of them took better than two months to clear customs which is rather odd as printed matter not for resale dose not need customs clearance .
A box of parts & tools from Tiny Tach took 6 days to arrive from the USA and it did need customs clearance .

Now having read the thread from start to finish just one other thing regarding seating tyres onto rims.
The speed of inflation is really important so next time try inflating with your air duster rammed into the empty valve tube.
I have to do this all the time to get mower tyres to seat properly.
The higher energy from the rapidly inflating tube is generally sufficient to overcome the static friction in a "funny" patch on the rim.
However it might be worthwile to turn down the regulator a bit as occasionally I have blown the tyre right off a rim using this method.
Funny to look at but not when it is your genetalia a few inches from the rapidly escaping air.
Posted By: BSA_WM20

Re: 1928 Ariel Model C - 01/19/18 1:37 pm

Originally Posted by gavin eisler
MM , luvvin it so far, the crank is 8 times better, great !, glad it was just the key. Fitting keys correctly is 2nd year apprentice stuff, you were very right to go through this motor, I reckon it will run like a sweetie, bad crank and twisted rod wouldnt have got too far.

,One thing that got a lot better after the 30s was exhaust valves, got any special plans there? Have you considered staged drops of castrol R , smell is a huge advantage.


That is why they are exposed.

Original valves were made from the same material used in aircraft engine because military research budgets are just about limitless.
And they were exposed to very fast moving air.
So it was not till WWII that the need for valve steels capable of running inside a cover became a problem to be overcome.
Any modern valve made with a Nimonic alloy will happily run inside a cover without overheating.
Unfortunately they are usually found in either diesels or top fulers but they can be turned down to size with carbide tooling.
Posted By: BSA_WM20

Re: 1928 Ariel Model C - 01/19/18 1:45 pm

Originally Posted by Magnetoman
I
With the crankshaft done this young man's fancy now lightly turns to thoughts of electroplating. Once I get the drive-side bearing plated and installed in the case I can slowly start putting the engine back together again. Unless it's Humpty Ariel...


If you have not yet done the plating,
Liquid electrical tape is another rubberised paint on solution that can be used to make a water tight coating that will not wick into palces where you don't want it.
Even better is you can use it to paint over the electrical connections to prevent corrosion on all of the fleet.
Works really well on the pre WWII light switch terminals as it not only prevent corrosion but also stope those tiny BA screws fron falling out.
I think some one already mentioned CRC soft seal which comes as a spray on, paint on or dip.
It is the same stuff that used to applied to the end of chisels in the days when they left the factory sharp enough to use.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/19/18 6:11 pm

Originally Posted by gavin eisler
you were very right to go through this motor ... bad crank and twisted rod wouldnt have got too far.
Some things the previous rebuilder did just fine, but others would have left me stranded well before we reached the Midwest. In the 2014 Cannonball an Italian purchased a bike sight-unseen based on a UK dealer's description of it and had the bike shipped directly to the start. He spent 99% of the time riding in the breakdown truck.

Originally Posted by gavin eisler
One thing that got a lot better after the 30s was exhaust valves, got any special plans there?
Originally Posted by BSA_WM20
Any modern valve made with a Nimonic alloy will happily run inside a cover without overheating.
Unfortunately they are usually found in either diesels or top fulers but they can be turned down to size with carbide tooling.
Either in an earlier post or off-line chaterlea25 also suggested diesel exhaust valves to modify. I'll investigate those options once I start work on the head and know the size I should look for. Diesel engines in cars have ~500cc cylinders so fingers crossed that finding an appropriate valve won't be too difficult.

I'm more worried at this point, needlessly I hope, about the valve springs. I can't count on the ones currently in it being correct or of good quality so I'll have to work out what's needed for myself and then hope something readily available can be substituted. Then there's the condition of the valve guides and seats to worry about once they've been revealed. The list goes on.

Originally Posted by gavin eisler
Have you considered staged drops of castrol R , smell is a huge advantage.
There's nothing like the smell of Castrol R, although the following riders would benefit from it more than me. There could be good reason to add a bit of oil to the fuel, but doing so drops the octane. Whether it drops it enough to cause knocking remains for me to see.

Originally Posted by BSA_WM20
The speed of inflation is really important so next time try inflating with your air duster rammed into the empty valve tube.
It's a good suggestion but, believe me, I tried that. I have a compressor with a large tank and with good size lines so it would be difficult to ram air in faster than I was able to.

Originally Posted by BSA_WM20
Liquid electrical tape is another rubberised paint on solution that can be used to make a water tight coating that will not wick into palces where you don't want it.
Re-reading the Caswell instructions they caution that the alkali solution can attack paint. Because of this I've already taped both sides with Kapton tape since Kapton shows 'excellent' resistance to nearly all chemicals, dropping only to 'good' for 25% lye. That's for Kapton itself, not for the glue, but I'll have to hope the very thin exposed line of it stands up to the plating solution for the required hour or so.

Posted By: Shane in Oz

Re: 1928 Ariel Model C - 01/19/18 10:07 pm

Originally Posted by Magnetoman
Originally Posted by gavin eisler
One thing that got a lot better after the 30s was exhaust valves, got any special plans there?
Originally Posted by BSA_WM20
Any modern valve made with a Nimonic alloy will happily run inside a cover without overheating.
Unfortunately they are usually found in either diesels or top fulers but they can be turned down to size with carbide tooling.
Either in an earlier post or off-line chaterlea25 also suggested diesel exhaust valves to modify. I'll investigate those options once I start work on the head and know the size I should look for. Diesel engines in cars have ~500cc cylinders so fingers crossed that finding an appropriate valve won't be too difficult.

I'm more worried at this point, needlessly I hope, about the valve springs. I can't count on the ones currently in it being correct or of good quality so I'll have to work out what's needed for myself and then hope something readily available can be substituted. Then there's the condition of the valve guides and seats to worry about once they've been revealed. The list goes on.

If it helps at all, Dragonfly has some info on valve dimensions

As far as the valve springs go, you can measure the spring rates of the existing springs in their working range and compare that to a known reference like, I dunno, a Gold Star.
One would expect the original spring rates were similar to later Ariel singles or a fairly softly tuned BSA single like a B31 or B33.

Something to consider with the valves is that guides are hard to replace, but valves are easy. As long as the head doesn't break off, which was way too common in the early days, it doesn't really matter if the valve stems wear and the valves have to be replaced on the rest day while the decoke is in progress. Any modern valves will have been engineered for far higher temperatures and engine speeds than you are likely to encounter, so mechanical failure is somewhat unlikely.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/19/18 10:36 pm

Originally Posted by Magnetoman
Either in an earlier post or off-line chaterlea25 also suggested diesel exhaust valves to modify.


I looked into this when looking at replacement valves for my IoE Harley. Its worth noting that most modern valves are made of 214N stainless steel. Stainless steel and cast iron valve guides don't like each other unless you surface treat the stainless so if you machine them you will need to get then treated or change the valve guides to bronze (although that also has issues with differential expansion in hot side valve valves). If you look at G&S valves website (they are the last UK manufacturer of valves) there is lots of information. Start here: http://www.gsvalves.co.uk/assets/g-s-technical-infomation.pdf But there is a lot more on their website and on the web in general


Originally Posted by Shane in Oz

Any modern valves will have been engineered for far higher temperatures and engine speeds than you are likely to encounter, so mechanical failure is somewhat unlikely.


I agree that the materials are much better now but modern engines have much better cooling.

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/20/18 3:01 am

Originally Posted by Shane in Oz
If it helps at all, Dragonfly has some info on valve dimensions
Unfortunately, my valves aren't on that list. The parts list gives mine as A6/98 (inlet) and A6/99 (exhaust).

Originally Posted by Shane in Oz
One would expect the original spring rates were similar to later Ariel singles or a fairly softly tuned BSA single like a B31 or B33.
My thoughts exactly. I just have to hope springs with reasonable rates have dimensions that are compatible with the Ariel.

Originally Posted by George Kaplan
Start here: http://www.gsvalves.co.uk/assets/g-s-technical-infomation.pdf But there is a lot more on their website and on the web in general
Thanks for the link. Once I figure out what might work I suspect I'll end up buying several choices for each valve, like I did with pistons and crankpins. Thankfully, the Ariel isn't a 4-valve V-12.


Turning to something else, I plated the drive-side bearing today. All went very well. Details to follow.
Posted By: Shane in Oz

Re: 1928 Ariel Model C - 01/20/18 5:41 am

Originally Posted by Magnetoman
Originally Posted by Shane in Oz
If it helps at all, Dragonfly has some info on valve dimensions
Unfortunately, my valves aren't on that list. The parts list gives mine as A6/98 (inlet) and A6/99 (exhaust).
Oh, well. It might be of some use finding something close after you measure the current valves. Widening the search a little, some Ford and Chev valves are very close if the Ariel has 3/8" stems.

Originally Posted by George Kaplan
Start here: http://www.gsvalves.co.uk/assets/g-s-technical-infomation.pdf But there is a lot more on their website and on the web in general
That one went straight to the pool room.
Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/20/18 8:09 am

Originally Posted by Magnetoman
Once I figure out what might work I suspect I'll end up buying several choices for each valve, like I did with pistons and crankpins. Thankfully, the Ariel isn't a 4-valve V-12..



I had thought that you already had something in mind, if not then it may be worth contacting G&S valves. When I spoke to them they were very helpful and if nothing suitable is available they will make bespoke valves in small quantities. I think they quoted me for a batch of 2, 6 or 10 for my 20F. However they list valves for lots of bikes in their vintage motorcycle range so they may find something close to what you need in their existing catalogue. See here:http://www.gsvalves.co.uk/catalogues.html

If you look at option of modifying a modern diesel valve then the problem I had was that the valve catalogues are all published in pdf format with differing formatting throughout. The catalogues are huge so in the absence of being able to convert easily to a searchable database it is a long tedious job looking for valves close to that you need. ( I found some Caterpillar ones close to what I need but it took some time to find them)

John
Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/20/18 9:17 am

Oh, I forgot to mention, when I spoke to G&S they didn't have valves for my 20F but had made them previously for someone else so they did have a drawing which they emailed me a pdf print of. If they have done valves for your Ariel previously they may have a drawing which they might share with you which may be of help if you decide to make enquiries closer to home.

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/20/18 7:14 pm

Originally Posted by Shane in Oz
some Ford and Chev valves...
Originally Posted by George Kaplan
... it may be worth contacting G&S valves
I'm afraid you guys are a few weeks ahead of me so please save those thoughts for later. There are still quite a few hours between now and when I'll have the bottom end assembled (rebalance crank, install bearing, install and line bore bushes, Cr plate and regrind cam spindles, ...). Back to plating:

The bearing OD is 2.5" x 3/4" for a surface area of 5.89 in.2. According to the Caswell instructions for Cu, a current of 0.07 A/in.2 will plate 0.001"/hr. (for an increase in diameter of 0.002"), which would mean a current of 0.412 A. This turned out not to be quite correct, but more on that later.

I followed the plating instructions more closely than most people might, but not to publication-level standards. Instructions say to "try to keep the anode at least 3" away from the article being plated and no more than 9" away." The issue with this is the bigger the container the more plating solution that is required to fill it to at least 3/4". With the Cu anode wrapped around the inner edge of a 7-1/4" glass container the bearing was 2-1/2" away and I had enough solution to just get to the top of the bearing. The instructions say you should try for 3", not that you must, so that's the container I used.

Not enough Cu sheet came with the kit I bought to cover the ~23" circumference of the container so I supplemented it with two 1"-wide strips of OFHC Cu to fill in the gaps and completely surround the bearing. I placed the bearing in the center of the container and preheated those items on a hot plate, without solution as yet, to roughly the 110 oF called for in the instructions. I then added the solution and waited until it was up to temperature. I did it in this order to minimize the time the Kapton would be in contact with the solution. Once the solution was up to temperature I turned on the power supply and adjusted the current for 0.41 A. Over the course of the next hour the temperature varied between 117 and 104 oF as I fiddled with the hot plate settings. I agitated the solution manually every few minutes by stirring with the thermometer. For what it's worth, the instructions say the plating voltage will be "2 volts approx" and I measured 1.74 V.

The Kapton tape itself was fine, but not the glue. I saw it lifting at the edges so placed a block of Teflon over the bearing to keep the tape flat. I'll try to find something better to use if I need to plate another bearing, and certainly before I hard chrome the cam spindles.

After an hour I removed the bearing, rinsed it, and measured the diameter. It should have increased by 0.002" according to the information in the Caswell manual, but it had increased by just under half that, 0.0008". I put new tape on the bearing and placed it back in the solution for another hour and a quarter at a ~25% higher current adjusted for the measured deposition rate during the first hour. At the end of the second plating session the diameter had increased by the total of 0.002" I wanted. The plating is uniform, varying by no more than ~0.0002" in my various measurements.

All reliable information on hydrogen embrittlement emphasizes the importance of having the least possible delay between plating and heat treating. So, after removing the tape and brass wire electrode around its circumference (which left a very narrow unplated line) I put it in the oven. No matter what it had been ~2-1/2 hrs. since hydrogen started infusing itself into the steel.

----------- Sidebar ------------
Nb. Most people will want to skip past this sidebar. I'm writing it more to document it for myself than for any one else.

You might think that it would be easy to find the answer to the question, at what temperature and for how long do I need to heat an electroplated part, but it's not. Far from it. This was a case of, the more I read, the less I felt I knew.

Hydrogen embrittlement is a very complex subject with the exact mechanism responsible still not understood after more than a century of study. To summarize a number of sources ranging from the Caswell manual ("The possibility... is remote"), to the web (" A simple hydrogen bake out cycle can be performed to reduce the risk of hydrogen damage ... Caution: over-tempering or softening of the steel can occur,..." to recent peer reviewed scientific publications ("...the mechanisms by which hydrogen embrittlement occur and the suitable means for its prevention are yet to be fully established."), basically, the required heat treatment depends on the exact composition and previous processing of the steel because that determines the diffusion constant of the hydrogen through the lattice.

Based on quite a bit of reading, originally I planned to use 375 oF to drive the hydrogen out but I subsequently found one reference to bearing steels that quoted the lower 275 oF figure. Looking further, technical information in the FAG catalog says bearings that will operate above 300 oF need special heat treatment. That refers to operating temperature, not temperature when static, so looking further I found that ball bearing balls and races are hardened at high temperature and then annealed at 300 oF to temper them. So, I decided to use the 275 oF value.

The issue with temperature is that removing the hydrogen is an exponentially activated diffusion process so a lower temperature is much less effective than a longer time. Dropping from 375 oF to 275 oF reduces the absolute temperature by a factor of 464 Kelvin/ 408 Kelvin = 1.14, but to compensate the time has to be increased by a factor of exp(1.14) = 3.12. So, I simply have to leave it in the oven for 3.12x longer than, well, longer than what? I couldn't find a reliable source for the time for a bearing steel.

I found that bearing races have a hardness of 58-62 Rockwell C, and the ASTM document B 850-98 (2009) Standard Guide for Post-Coating Treatments of Steel for Reducing the Risk of Hydrogen Embrittlement has a table of heat treatment times at 375 oF for hardness values from 31 up to 51. Extrapolating those values to ~61 gives a time of ~30 hours. Multiplying by 3.12x gives ~94 hrs. Based on this quasi-scientific analysis, I'll be heat treating the Ariel's bearing at 275 oF for roughly 4 days.
---------------- end sidebar ---------------

The bearing has been in the oven at 275 oF for ~20 hours as I upload this so it has another 3 days to cook.
Posted By: koan58

Re: 1928 Ariel Model C - 01/21/18 3:07 am

I've been looking forward to this electrochemical bit.
The project when doing my degree, was on the solubility of hydrogen in various alloys.
This was the late 1970's.
The idea in our minds at the time was to store hydrogen in a safe form for use in vehicles.
Our favourite alloy at the time was of titanium/iron. The lattice was distorted such that it "welcomed" hydrogen interstitially to lower its energy state.
Its welcome was so strong, that with a pressure of a few atm, it would hold more H than you could fit in the same volume of liquid H2.
It only required a little lowering of pressure and/or modest warming, and the fuel was released in a controlled way.
It was even demonstrated in the mid 80's in a BBC programme called Horizon, where efforts were made to explode/ignite this lump of concentrated hydrogen.
It could not explode or combust in any significant manner, because the hydrogen could not diffuse rapidly enough to the surface.

This is where I draw a parallel to your hydrogen embrittlement situation.

The hydrogen ions produced by electrolysis are attracted toward the same target as the copper ions.
The huge copper ions can only stick in the rough surface of the steel.
However, hydrogen ions (protons) are small enough to burrow in between any metal atoms, disrupting the ordered strength of the crystal lattice, inducing stress.
You are right to describe this as diffusion, it is like osmosis in a way, but it is the solute (hydrogen) which is migrating.
The rate at which hydrogen can diffuse through a metal like bearing steel could only be tiny, nanometres per month for arguments sake, especially as you have no potential drawing inwards.
In a nutshell, I think any hydrogen will be limited to the outer 2,3 or 4 atomic layers, and as such easily driven off by your heat treatment. I'd be doubtful that it would matter anyway. If it were near to a bearing surface, it may matter more?

As yet, my intterest in the 70's hasn't spawned any fruit in the way intended, though oddly the solubility of hydrogen in various alloys has become relevant in for example, NIMH cells.
Posted By: BSA_WM20

Re: 1928 Ariel Model C - 01/21/18 11:29 am

Going off topic again,
Koan,
That is rivitingly interesting.
So what stops the H ions migrating through the lattice then forming H2 molecules which rip the lattice apart under external stress ?
As an undergraduate I worked with Prof Muir on his project determining hydrogen gas precipitation at the root tip of cracks in maraging steels, for which he was awarded an ACTA Metallurgia.
I was several years after the award when he was widening the investigations into the same mechanisms which lead on to the brand new field of fracture toughness.

With relatively low concentrations of H2 generation we could get cracks to rip through steels at phenomenal rates.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/21/18 7:54 pm

Everything you need to know about hydrogen-powered vehicles you can learn in 1 min. at:

https://www.youtube.com/watch?v=jH-mhZLuGRk

and about hydrogen embrittlement in electroplated films in 20 sec. at:

https://www.youtube.com/watch?v=u0nqcpHHImo

Although I was being facetious with the first video, the "hydrogen economy" hasn't lived up to the promise it seemed to have when proposed nearly 50 years ago.
Posted By: BSA_WM20

Re: 1928 Ariel Model C - 01/22/18 12:21 am

And atomic fusion has not quite lived up the expectations either, apparently we are just 10 years or so from cracking it which is where we were when I was an undergraduate , perhaps they are Pluto years.

The hydrogen economy is here right now but like a lot of things that challenge the existing economic structure, those who suffer finanacially from it are doing their utmost to delay it.
Hydrogen welding is now done industrially and is rapidly knocking acetylene out as the preferred fuel. BOC ( CIG here) has done all it could to prevent this happening in Oz & I am sure the gas suppliers in the USA have done the same.
Hydrogen generators are readily available but I have not seen any offered by major gas companies, then again I have not been looking all that hard either.
When the government slapped an enviromental levly on acetylene down here doubling it's price I did have look but decided it was not worth the effort at this point in time .

Back in the 90's UNSW had pilot electryolys plants working but funding got cut, no doubt due to the influence of both the coal industry & supported by the royalty seeking individual State governments.
Several plants were set up at near commercial scale in various Pacific Islands as part of the foreign aid budget because they could not get research funding and AFAIK they are still running but the people I knew who were involved with this are long out of my social circle.

We seem to be drifting again, hope the life is teathered securely to the Ariel .

On the subject of hydrogen enbrittlement, I can not think of any work done on it under compressive loading, only tensile & shear, but mostly tensile .
While the mechanism for hydrogen migration througn a lattice under tensile strain should be the same as migrating under compressive strain I really could not see your bearing fracturing during use.
As it will be running at elevated temperatures I would imagine that hydrogen gas would continue to be exuded by the bearing during use.

Thin films and monocrystaline fibres are great for research purposes and in particular make the maths accessible ( buy don't ask me to do it now ) the actual bulk mechanical properties are somewhat different in real life applications.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/22/18 2:47 am

Originally Posted by BSA_WM20
atomic fusion has not quite lived up the expectations either, apparently we are just 10 years or so from cracking it which is where we were when I was an undergraduate
I have a newspaper clipping from the mid-1970s in my office when, while visiting a research facility, the then-Secretary of the Department of Energy commented that it appeared producing energy from fusion research might be faster if we just burned the money. Although it is especially noticeable when it happens with major research projects, the nature of research is that the outcome is judged promising enough at the outset to pursue, but by no means can it be guaranteed.

With the bearing slow roasting for two more days I returned to the flywheel. The first order of business was to double-check that all drillings in the flywheels and crankpin were clean. Then back on the rollers to see what needed to be done to balance it to be 65% with the Omega piston as I had determined the original balance factor to be.

My notes show the weight of the complete Omega piston assembly (piston, rings, gudgeon pin, and clips) was 435.0 +/-0.5 g, but I reweighed it to be sure and got the identical result. I had machined and installed a new bush for the small end and, when the crankshaft was apart, was able to accurately weigh the small and big ends to be 267.0+/-0.5 g and 291.0+/-0.5 g, respectively, vs. the 267.5+/-1 g of the small end I had previously measured in situ with the old bush.

Up until now I had been checking the balance using a pair of bearings with the same OD but with 7/8" and 1" IDs to level the crankshaft on the wheels. However, the bearings are narrow enough that they can "walk" off the rollers after enough rotations so I took the time to machine two sleeves from 1-1/4" OD material, reamed 7/8" and 1". This was much more satisfactory.

After spending quite a bit of time I'm not convinced I can reliably determine the balance to better than +/- 2.5 grams hanging from the connecting rod, which is equivalent to 1.1 g at the edge of a flywheel. According to the specs I should be able to get to ~0.1 g but that wasn't possible (due, it appears, to residual friction of the big end rollers). Anyway, 2.5 g more than 193 g definitely was a bit too much, and 2.5 g less definitely was a bit too little. As will be seen from the final calculation, being able to balance it better than this wouldn't make a difference in my conclusion.

Plugging the measurements into a reduced form of an earlier post results in the following if I use the crankshaft as-is:

Balance Factor = balance weight + small end weight / piston weight + small end weight

Balance weight:

-- weight to balance crankshaft in its present form = 193.0 +/-2.5 g

Small end weight:

-- Current small end weight = 267.0 +/-0.5 g

Piston weight:

The "piston weight" is that of the complete assembly of piston, gudgeon pin, circlips and rings.

-- weight of aftermarket +60 Omega piston assembly = 435.0 +/-0.5 g

Balance factor with Omega piston:

193.0 + 267.0 / 435.0 + 267.0 = 460.0 / 702.0 = 65.5 +/-0.4%

Thanks to a happy coincidence, within experimental uncertainty this is identical to the 65% I determined the original factory balance factor to be (actually, I found I found 64.8+/-1%). So, I'm going to leave the crankshaft as-is and bore the cylinder for the Omega piston.

If instead I used the Gandini piston as-is the balance factor would be 58.7%.

Posted By: koan58

Re: 1928 Ariel Model C - 01/22/18 5:53 pm

Thanks for the videos! I've always been amazed that some survivors ran away from that, I can only imagine that the updraft brought cool air in just long enough.
I actually found the 2nd vid fascinating, I know I must get a life!
It is all about stress fracture, and I have no problem with this, and WM20's info. Under stress, any flaw has a tendency to open, increasing access for hydrogen. This is not what is going on during electroplating a quality ground surface.
Plating using one of the "semi-noble" metals, employing an appropriately low current, will not result in significant H+ production in the 1st place.
The only dangerous possible penetrations would be where crystalline imperfections already exist at the surface, but as it isn't a stressful situation?
H can and will creep into a metal lattice through the surface, this is a very different phenomenon to penetration through fractures, and where the penetration is at the already most vulnerable point. There is also little opportunity for H2 (vastly larger than H) to form within the lattice, where space is available there is already structural vacancy.
WM20, Why would you think that adsorption would be unchanged with compression/tension? When H is adsorbed into a metal, the volume increases slightly, of course. The ease with which this can happen is affected by how you squeeze or stretch the sponge.
Your talk of H2 formation applies as you said, at the fracture point in a tensile situation.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/22/18 7:45 pm

Originally Posted by koan58
Plating using one of the "semi-noble" metals, employing an appropriately low current, will not result in significant H+ production in the 1st place.
If the electroplating process were 100% efficient all I would have to do would be to count the number of electrons that entered the solution (current x time) and I would know the exact number of Cu atoms deposited. However, it isn't 100% efficient as evidenced by the visible bubbles of hydrogen gas when I plated the bearing. This happens because some of the electrons are hijacked by the H+ ions to allow the formation of H2 gas (the chemistry is a little more complicated but this captures the essence). "Low current" wouldn't help since, say, one-tenth the current would just take ten times as long. The total amount of hydrogen produced would be the same.
Posted By: KevinN

Re: 1928 Ariel Model C - 01/22/18 8:01 pm

Originally Posted by Magnetoman


With the bearing slow roasting for two more days I returned to the flywheel. The first order of business was to double-check that all drillings in the flywheels and crankpin were clean. Then back on the rollers to see what needed to be done to balance it to be 65% with the Omega piston as I had determined the original balance factor to be.

...snip...

Thanks to a happy coincidence, within experimental uncertainty this is identical to the 65% I determined the original factory balance factor to be (actually, I found I found 64.8+/-1%). So, I'm going to leave the crankshaft as-is and bore the cylinder for the Omega piston.



Don't you love it when things work out!
You must be living right.
Good job.


Kevin

.
Posted By: koan58

Re: 1928 Ariel Model C - 01/22/18 8:29 pm

If there were no metal ions in the electrolyte (eg if it were just water or sulphuric acid), then the flow of +ve ions to the cathode could only be H+.
For electroplating, the electrolyte contains the desired metal ions, which will be replenished by the anode as they are deposited.
In this case, both Cu++ and H+ ions are available.
Cu++ are more readily made at low potential. However, their migration is much slower than H+.
So if the current exceeds what Cu++ migration can support, the excess will be performed by H+.
The optimum recommended current will be a compromise between reasonable plating time and tolerable hydrogen production.
There is no doubt that increasing current will result in greater hydrogen produced in proportion to copper deposited.
Posted By: quinten

Re: 1928 Ariel Model C - 01/22/18 8:48 pm


I can't remember... how was the cathode attached to the bearing race ?
And did it interfere, in any way, with the depositing of the copper ?
.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/22/18 9:12 pm

Originally Posted by KevinN
You must be living right.
I owe it all to clean living... no, wait, obviously there must be another explanation...

I'd hate to think how many hours it took for me to simply determine the goal was 65%. Measurements, calculations, tracking down original Hepolite pistons, etc. If only the 65% figure had been documented some place it could have saved all that time. That's why I'm documenting what I'm doing so the one other Black Ariel owner in the world who might come along in the future won't be starting from scratch. The same thing can be said for your thread on the AMCA forum. If I owned a pre-'20s Indian I would be very grateful for the detail you've been providing.

Originally Posted by koan58
If there were no metal ions in the electrolyte...
This is straying a bit off topic. I'll just leave it for now by saying that it is known that all plated coatings on all steels are susceptible to hydrogen embrittlement to some degree, with the problem more severe for higher strength steels, requiring a suitable bakeout as quickly as possible after the plating is finished. I'll return to electroplating when I deal with depositing hard chrome on the worn spindles of my camshaft.

Originally Posted by quinten
I can't remember... how was the cathode attached to the bearing race ?
And did it interfere, in any way, with the depositing of the copper ?
I don't have the brass wire I used handy at the moment but its diameter was about that of typical safety wire (~0.030"). I wrapped it once around the circumference of the outer race and twisted it tight with safety wire pliers. Although I used brass wire, stainless would have been fine. The wire masked the area under it but that only reduced the coverage by ~0.03" out of the 0.75" width of the race (~4%). I could have devised something more complicated to avoid that strip but, since I was doing this to provide an interference fit, not for a cosmetic coating, the appearance doesn't matter nor should the loss of 4% of the gripping force.

I checked again this morning and it's still cooking away with another ~18 hours to go.

Posted By: quinten

Re: 1928 Ariel Model C - 01/22/18 10:27 pm


Thanks,

What was process for choosing copper as the plating material , as opposed to say... nickel ?
Ease of plating,
Toxicity of electrolyte , cost ?
.
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/22/18 11:20 pm

Originally Posted by quinten
What was process for choosing copper as the plating material , as opposed to say... nickel ?
Less "research" went into my choice of Cu than into some of the other things I do. Any metal I could deposit to a thickness of 0.001" would have been fine for this purpose. For that matter, if it would have been possible to wrap the bearing with 0.001" steel or brass shim stock and press it into place without destroying the shim stock, that approach would have been fine as well.

That said, I've done plating in the past so I know Cu is pretty well behaved. Also, one of the reasons it's used as the first layer in "triple chrome" plating is because it adheres well to steel. For my purposes Ni probably would have deposited just as well onto the bearing, but I "knew" Cu would deposit in a uniform coating, vs. being "pretty sure" Ni would.

Another factor in my choice of Cu is it can be plated on pot metal. In the back of my mind is the idea to sometime experiment with using it to build up worn carburetor components. I don't have anything in particular in mind right now, but having the Cu solution in hand means I could try it without any (additional) expense. If it worked to reclaim whatever pot metal component I tried it on, great, and if it didn't, it wouldn't have cost anything.
Posted By: BSA_WM20

Re: 1928 Ariel Model C - 01/23/18 4:52 am

Originally Posted by quinten

Thanks,

What was process for choosing copper as the plating material , as opposed to say... nickel ?
Ease of plating,
Toxicity of electrolyte , cost ?
.


Nickel plating is notorious for hydrogen embritlement and most of the research in the early days was done on nickel plate.

At the interface of the bearing & the plating solution if hydrogen is generated then it will be drawn into the metal by the loose electrons which is the nature of the metallic bond.
Once in the structure it can & will travel quite freely as it is a very small atom ( well proton actually ) happily sharing electrons so will migrate along paths of slightly higher negative valence or get pushed around by the positative valence of the steel's atoms.

However like Koan said, if the plating current is slow there should be next to no H disolving ino the steel.
Posted By: BSA_WM20

Re: 1928 Ariel Model C - 01/23/18 5:14 am

Originally Posted by koan58

WM20, Why would you think that adsorption would be unchanged with compression/tension? When H is adsorbed into a metal, the volume increases slightly, of course. The ease with which this can happen is affected by how you squeeze or stretch the sponge.
Your talk of H2 formation applies as you said, at the fracture point in a tensile situation.


We did not look at H being adsorbed from the atmosphere.
We were looking at H that was already in the lattice ( a lot more than you would think ) migrating to the crack tip.
What actually forces the steel atoms to separate and thus the crack to grow, is not the applied stress shattering bonds but the H2 produced internally shattering the bonds.
This is why the research was so important .
We were only looking at the H2 evolution inside a metallic grain and not grain boundry H2 generation, which is the prime process in hydrogen embrittlement.
You get substantial amount of H2 at the grain boundries thus creating a lot of stress so substantially less load than would normally be required to initate failure cause a grain foundry failure.
And while not being 100% accurate , brittle failures in steels are grain boundry failures.
The test wires were made from vacuum remelted steel and the volume of H that gets liberated from the melt pool on the first remelt was really astounding. ( well it surprised me anyway ).
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/23/18 6:42 pm

Hydrogen
Originally Posted by BSA_WM20
However like Koan said, if the plating current is slow there should be next to no H disolving ino the steel.
I disagree. While reducing the current reduces the rate of hydrogen production, it also reduces the deposition rate of the Cu so the part has to stay in the solution exposed to hydrogen ions proportionally longer. The time a part can be exposed before the ingress of hydrogen is irreversible despite subsequent heating is in single digits of hours so longer has potentially severe consequences.

For me to go further down this hydrogenated side road by supplying references to the technical literature would require time I need to use for making progress on this rebuild so I'm stepping away from electroplating for now. If there are further H posts please don't take my lack of response to them as tacit agreement.

Crankshaft
Because there seemed to be a bit of stiction in the rod when I was measuring the balance factor I installed the crank in the lathe, put it in back gear, and spun it at ~60 rpm for two minutes while holding the rod away from the ways. I used plenty of oil on the crankpin, and felt no resistance at all. I then took it out of back gear to let the chuck spin free and spun the crank by hand by pumping the rod. Again, no resistance or rough spots.

With the crank now reacquainted with its task of spinning I put it back on the rollers where I found I now had more sensitivity. The balance weight is now at the low end of the range in my earlier post, i.e. the balance factor even closer to 65.0%. However, hard as it was to fight OCD, I forced myself to accept good enough as good enough and not to spend any more time determining the weight even more accurately. There are many other tasks that are more important to spend my time on. So, I'm certifying the crankshaft as fit to return to service with an Omega piston.

Bearing
This morning the drive-side bearing had racked up enough hours to rid itself of H so I turned off the oven, opened the door, and let it cool in air as it had during the tempering cycle when manufactured. The Cu coating had discolored but passed the rub-hard-with-thumb adhesion test. Also it's still 0.002" thick.

Since the bearing had been pretty hot for a long time I wanted to be sure the hardness had not been affected so I measured it and a companion RHP bearing I purchased at about the same time, although the latter with 'Standard" clearance. Also, the non-plated bearing came in a box labeled "RHP, member of the NSK Group" so it was manufactured more recently than the RHP I plated, and possibly not in the same facility.

All the information on bearing hardness seems to fall between 58 and 64 Rockwell C. First I checked my tester against a 49+/-1 Rockwell calibration block, and then tested both bearings at several locations on the outside edges of the inner and outer races. The newer RHP/NSK bearing consistently tested at 65 Rockwell, while the plated one came in a bit lower at 61-62. While these differences are (just) within the claimed +/-1.5 Rockwell absolute accuracy of my tester, the side-by-side comparison leaves no doubt the newer bearing is a bit harder. However, 61-62 is within what bearings should have and, since I didn't measure it before the heating cycle, the hardness certainly could be identical to the value it had at the start.

The next order of business will be to install the bearing in the case. Taking a low value for the thermal expansion of Al along with the value given for bearing steel, the differential thermal expansion between the bearing straight from the freezer and the case pulled from a pot of boiling water should be ~0.0025". So, the bearing should drop into place with very little urging and the friction not be an issue for the relatively soft Cu. Again, I decided on 0.002" as the "press fit" because BSA Service Sheet says this bearing should drop out of the case if it is heated in boiling water.

p.s. the brass wire I wrapped around the bearing to make electrical contact is 0.039" in diameter, although the track it left behind is only 0.015" wide, so only 2% of the surface was left unplated.


Attached picture IMG_6432.JPG
Attached picture IMG_6439.JPG
Posted By: George Kaplan

Re: 1928 Ariel Model C - 01/23/18 7:57 pm

Great stuff MM, now that you have finished baking your cookie you are now starting the reassembly process so it seems to me that you have passed a key milestone. We are in mid (ish) January so I think you are on reasonable course to have the bike ready in plenty of time to test ride it enough and iron out all of the bugs.

Keep up the good work.

John
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/24/18 1:32 am

Originally Posted by George Kaplan
I think you are on reasonable course to have the bike ready in plenty of time to test ride it enough and iron out all of the bugs.
Knock wood that your good wishes haven't jinxed it...

My most recent around-the-world trip along with its subsequent jet lag and the holidays kept me from making much progress during December, but things are nicely moving forward again. So far... (see above paragraph).

I have a large galvanized tub (20" dia. x 10" deep) that I'm forbidden to use ever again on the barbeque to degrease stubborn engine parts. It's amazing how acrid the smell and how long it lingers... But, this time it was just to heat a clean case in water so that's what I used. I tied a string to the case to use to haul it out of the boiling water.

I had placed the bearing in a baggie in the freezer at ~0 oF an hour or so earlier and the IR thermometer said it already was down to 18 oF when I fired up the barbeque. To have everything ready I laid out a quadruple thickness of towel so the case would be insulated from the counter top and cool more slowly, a socket with 2.48" OD, a Cu hammer for additional encouragement if required, and a pair of thick gloves.

The better part of an hour later the bearing was at 8 oF when the water started boiling. I wrapped the bearing in a towel to carry outside, quickly had the case in place on its towel, and just as quickly had the bearing installed. However, it was good I had the hammer and socket ready because I needed them.

The case is now cool and the bearing spins freely but with no sign of clearance, which confirms the fact that, like with a Gold Star, a C3 bearing coupled with 0.002" press fit is the way to go. I wonder how tight the original CN bearing I bought would have been had I used it instead.

I had carefully cleaned the bearing of all oil nearly five days ago so I generously lubricated it with lathe spindle oil from a pump oil can I had handy. Examined closely under a microscope there is no sign of Cu anywhere around the interface between the bearing and housing, which would have been there had any peeled or scraped off the surface during the installation. I'm very happy with how this turned out. Fingers crossed that this attention to detail pays off in September.

There's still plenty to do but, as John wrote in the previous post, it's now almost ready to (slowly) start going back together. As soon as I make and line bore three bushes on the timing side the bottom end will be ready to assemble. I already have the jig needed to bolt the cases to the mill since I made it to clean up the distorted hole for the drive-side bearing a month or two ago (which is why I needed to plate the bearing oversize).
Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/25/18 1:54 am

The clearance in the present timing side crankshaft bush varies between 0.0045" and 0.0057" so it definitely needs to be replaced. However, I'm a bit puzzled by my measurements at the moment.

Normally non-custom tooling is used to ream a bush to a standard dimension and the shaft made sufficiently undersize to allow clearance for the oil. The only comparable figure for a crankshaft I've found so far is Nicholson who gives 1.3735" as the standard diameter for the timing side of a BSA A10 crankshaft, which would mean a clearance of 0.0015" when new if the bush were reamed to a standard 1-3/8". Consistent with this, separately he gives a minimum of 0.0015" clearance when a new bush is installed. Also consistent with this, a pre-unit BSA gearbox layshaft is 0.002" smaller than the bush, which itself is reamed to a standard diameter. Further, Nicholson notes that if the clearance has increased to 0.003" the bush needs to be replaced.

As for the Ariel, the shaft projects ~1-3/4" from the flywheel. Other than the outermost ~1/2" where the wear is more (it tapers to 0.8738" at the very end), over most of the length the diameter varies from 0.8741" at the smallest to 0.8743" at the largest. This would result in clearances of only 0.0007"-0.0009" if the bush were reamed to a standard 0.8750". I could machine a new bush with any ID I wanted, but I'm puzzled why it doesn't appear to have been a standard size when new. Or, if it was a standard 7/8", why Ariel made the clearance so small. I'll give some more thought to this before I make the replacement bush.

Once again it sucks not living in North Korea, because if I did I would be ecstatic if I could get my hands on any kind of bronze in the next six months, rather than being forced to select between scores of different varieties (most of which could be delivered by Friday, if not tomorrow).

I still have enough of the PB1 tin bronze (ASTM 90700 or SAE 65 nearest U.S. equivalent) that chaterlea25 sent me a few months ago, that I used for the small end of the connecting rod, and it has a large enough diameter for the 1-3/8" "hat" on the end of the 1-1/8" OD bush, but I'm leaning toward using "high strength" 544 phosphor bronze for this crankshaft bush instead. If the bush in the rod doesn't distort with the PB1's 25 ksi yield strength, the one for the crankshaft should be fine with the 544's 50 ksi. However, the jobs the two bushes do are different.

Both bushes are subjected to the hammering of combustion (although the crankshaft bush shares it with the drive-side bearing), but the small end sees the gudgeon pin oscillate back and forth by only ~+/-20o so the surface speed of the pin over the bush is relatively small (pi x 13/16" x 40/360 x 5000 rpm = 120 ft./min.) whereas the crankshaft bush sees the spindle rotate at fairly high surface speeds (pi x 7/8" x 5000 rpm = 1100 ft./min.). Further, the small end bush has a clearance of only a few ten thousandths while that of the crankshaft bush is ten times larger because it relies on a hydrodynamic cushion of oil. Again, not living in North Korea forces me to read specifications to try to decide on the best bronze for the application.

Once I decide on the material for the bush and make it I'll need to shim the crankshaft for the correct end float when the crankcases are bolted together. Ariel uses shims for this purpose and a few of them were in place when I disassembled the engine. Draganfly supplies a set of these shims in a variety of thicknesses for only ~$10 including postage so, although I don't know if I will need them, I ordered a set.
Posted By: gunner

Re: 1928 Ariel Model C - 01/25/18 6:17 am

Many of the TS bushes available in the UK for the BSA A65 are made from solid lead bronze (SAE 660). Apparently this Bronze has good hardness and strength qualities as well as good wear resistance, it also has excellent machining properties and anti-friction qualities. Additionally I note that SRM sell TS bushes for the A65 made from phosphor bronze (PB1) which is suitable for bearings having medium to high loads and speeds and good resistance to impact loading or pounding.

I have no idea whether either of these bronzes are suitable for your application but to help you decide, there's a long article on selecting bronze bearing materials, see This Link
Posted By: kommando

Re: 1928 Ariel Model C - 01/25/18 8:24 am

As you are using unfiltered oil, noting that it is total loss, you need to include embedability in your list of properties when selecting your bush material. Use a material with low embedability and any hard debris build up on the surface will convert your bush into a grinding wheel. Lead bronzes can suffer from this hence Vandervell's use of soft lead/indium overlay plating and Glaciers soft lead/tin overlay, these acted as sinks for debris as they are so soft its kept below the surface but kept the strength of the leaded bronze subtrate plus were more resistant to acids from combustion. That's not an option here but watch out for the temptation of using the highest fatigue strength.
Posted By: gavin eisler

Re: 1928 Ariel Model C - 01/25/18 12:41 pm

When SRM was still Steve MacFarlane they/he offered a service for A10/ a65s where the timing side journal was fitted with a hard sleeve to minimise journal wear , just a thought.
Re bush clearance
"This would result in clearances of only 0.0007"-0.0009" if the bush were reamed to a standard 0.8750"."
This fits pretty well to the old one thou clearance per inch of shaft diameter for bush clearance.
Posted By: gunner

Re: 1928 Ariel Model C - 01/25/18 1:06 pm

I've heard about the hardened steel sleeve on the journal and also hard chroming the journal to increase service life.

I guess in principle its better to have the bush wear rather than the journal, especially on a rare vintage bike where spares are hard to get.

Its interesting to note that modern cars can run for many hundreds of thousand miles using bushes and journals to support the crank. Presumably the engineers have found the ideal match of crankshaft material and bush material together with high quality filtered oil.
Posted By: kommando

Re: 1928 Ariel Model C - 01/25/18 2:23 pm

Its a lot to do with improved oils and the extra oil film strength you get, if the oil film never breaks down then you can get away with a much lower fatigue strength as direct contact journal to bearing never takes place. The Cu/Pb high fatigue bearings are being dropped in favour of lower fatigue strength Al/Sn with a touch of copper with special heat treatments and other variations (they offer fatigue strengths higher than the old Al/Sn bearing but still not to Cu/Pb levels and are much cheaper) together with nodular steel cranks (these are conditioned by the newer Al/Sn bearings during the first 100 miles). Now where Cu/Pb is really needed such as high performance engines such as racing and the high output Diesel there are even better bearing materials with higher fatigue strength so it is being hit from both ends and is being marginalised. Sputter bearings are one example of these new high fatigue strength materials (used on the lower big end shell only due to cost).

https://www.highpowermedia.com/blog/3445/what-are-sputtered-bearings

So successful are these newer materials that aftermarket bearing market is also being killed off.

Sadly none of these newer materials can be retrofitted to old engines without the oil delivery system be completely overhauled and these new manufacturing processes are high volume and low batch sizes would be too costly. One of them uses a mini jet engine to blow atomised Al/Sn over a Al/Sn on steel substrate. a robot controls the spraying.
Posted By: Tridentman

Re: 1928 Ariel Model C - 01/25/18 3:15 pm

K--that is very interesting.
Reminds me of work I was involved in at the AE RE&D Center in the late 1960s---plasma spraying the leading edge of turbine blades for Rolls Royce aero engine to refurb them rather than just throwing them away.
With spraying techniques you can get some interesting and very useful combinations of materials and thus characteristics.
Sorry to go off at a tangent!
Posted By: quinten

Re: 1928 Ariel Model C - 01/25/18 5:44 pm


Those new bearing materials are cool
But The engine in question here , as hot as it may look , is more lawn mower than race car.
Low hp, low compression and low oil pressure.
I think the bearing may need to survive where lubrication may be low or interrupted.
Maybe an old school 80-10-10 lead-bronze ?

.

Posted By: Magnetoman

Re: 1928 Ariel Model C - 01/25/18 6:32 pm

Thanks very much guys for the quite helpful responses. When I'm not certain of the best way to proceed I post something like "I'm thinking of..." in the hopes of getting other insights and information.

In addition to the posts on Britbike, offline Triless sent a page from a 1930s manual for Matchless X and AJS big twins showing their timing side bearings should be "reamed in position to 7/8" +0.00075/-0". However, it doesn't give the diameter of the spindle that will go in it so I can't tell from this what clearance those bikes used.

Unfortunately, the important "embeddability" isn't among the properties of bearing materials that are listed by suppliers. That link gunner included discusses the importance of this property, but it fails to recommend a bronze that excels at it.

Also not helpful are qualitative descriptions like "light duty" or "low load." Compared with what? The bushing for a steamship's propeller shaft, or for a 1/10 h.p. electric motor? Focusing on 660, one supplier describes bushes made from it as "used for general utility applications under medium loads and speeds, "while another says it is "the standard bearing material for light duty applications," and another says "ample strength and hardness, adequate ductility." I'm reminded of a Gene Hackman line in 'The Unforgiven': Ample? Ample for what?

Unlike my N. Korean counterpart who would be happy to use any bronze he could get his hands on, I have the following bearing bronzes "i