Classic British SparesKlempf British PartsBaxter CycleBritBike Sponsor SteadfastCyclesSRM EngineeringLucas Classic MotorcycleIndustrial tec supplyHepolite PistonsThe Bonneville Shop

Upgrade your membership to: Premium Membership | Gold Membership | Life Membership | Vendor Membership | Site Sponsor Membership
Welcome to BritBike Forum!
Britbike forum logo
Member Spotlight
BeezaBryan
BeezaBryan
Derbyshire UK
Posts: 3,510
Joined: April 2006
ShoutChat
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Top Posters(30 Days)
Allan G 80
quinten 51
Top Likes Received (30 Days)
Cyborg 19
Newest Members
Steve W 1959, Bobpin, VWK740, Alloy Clipper, DonB
11,757 Registered Users
Who's Online Now
8 members (Mikeyd, Nomad6T, SpeedyV, bones_bir, koan58, L.A.B., Andy Higham, Dibnah), 31 guests, and 76 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Page 125 of 133 1 2 123 124 125 126 127 132 133
Joined: Feb 2019
Posts: 520
Likes: 216
S
Britbike forum member
Offline
Britbike forum member
S
Joined: Feb 2019
Posts: 520
Likes: 216
Originally Posted by Magnetoman
[Linked Image]
As can be seen, the groove has a quite=appropriate pitch of ~0.9". Also, it can be seen where the groove emerges from the bush.
Well done. That is as nice as anyone could want. Excellent effort.

This section also shows why proper mechanical restoration is so costly and why it is often neglected. 1 or 2 off custom parts aren't cheap.

1 member likes this: Magnetoman
Support Your #1 BritBike Forum!

Check out British motorcycles for sale: British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
Originally Posted by StuartKirk
Well done. ... shows why proper mechanical restoration is so costly and why it is often neglected.
Thanks very much.

According to google the average rate charged by machine shops in the U.S. is $60-$80/hour, welding shops $65-$125/hour, and automotive shops $100-$150/hour. Lumping these together, call that $100/hour for a shop that does the types of work required to rebuild the Ariel gearbox.

My work on this gearbox (which still needs assembly) was spread out over three weeks. But, knowing what I know now about Burman gearboxes, my guess/estimate that if I had to do another one six months from now, when jigs had been put away and the knowledge was no longer fresh, is it would take the equivalent of roughly three full days (disassemble and clean, TIG and machine case, machine O-ring groove, make and hone bushes, turn layshaft, install bearing, reassemble). That means if I had to pay a shop to do the work, it would be $2400. Say three times that for the engine, plus the girder forks, rebuilding the magneto, and work on the wheels and clutch, and just the mechanical work on a complete restoration of an already functional (but internally worn) motorcycle would be $10k. This is only a rough estimate, but I doubt if it's too high.

It should be clear that it would be much less expensive to restore a motorcycle using glossy paint and chrome plating rather than increase the costs by using lathes, mills and TIG. There are many beautiful machines at auctions but, unless you already have the machine tools and your labor is worthless like mine is, it might be worthwhile to keep the $10k figure in mind for the additional cost of everything you can't see when about to bid on one of them.

Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
If the foreman had been on duty in the garage today I would have been sent home early for holding up the assembly line. However, even working at a slow pace I managed to get some things done.

In installing the stones for honing the bushes I realized some of the slots in the drawers were low and, in a few cases, empty. It would be very frustrating if honing were the last step required on a job and only then I discovered the necessary stone was missing. So, I made a note of ones that I should have and got them ordered.

I already had returned the lathe to its standard configuration but the rotary table was still on the mill, from when I used it to form the new Al on the gearbox outer cover. So, I returned it to the shelf and cleaned up the area.

Although the answer doesn't matter as far as this gearbox rebuild goes, I was curious what roughness the hone left on the bushes. Sunnen has a table that gives the "Approximate Surface Finish in Microinches" for 500 grit stones on Al, brass and bronze as 12 µ". As the photograph shows, the roughness I achieved was somewhat greater than this, at 21 µ"

[Linked Image]

However, Sunnen also has a formula for the amount of stock that has to be removed in order to achieve a given surface finish:

[existing finish – final finish] / 100,000 = required stock removal

I don't know what the existing/initial finish was, but since I removed ~0.003", and I measured the final finish, the above equation becomes

[existing finish - 21] / 100,000 = 0.003"

Solving this equation says the lathe left an rms roughness of 0.00032" (i.e. peak-to-peak ~0.001"), which is quite reasonable. In any case, the 21 µ" roughness is more than acceptable for a bush in this application.

I then cleaned and degreased the gearbox parts that still needed it, laid everything out ready for assembly, and loosely assembled the shifter arm.

[Linked Image]

At that point the last of today's already-meagre motivation for work drained from my body and I decided my time would be better spent sipping a margarita and watching the sun set behind the mountains. As for assembling the gearbox, there's always mañana...

Joined: Mar 2019
Posts: 844
Likes: 182
Member
Offline
Member
Joined: Mar 2019
Posts: 844
Likes: 182
Roll credits....


1970 T120R - 'Anton'
1970 Commando - 'Bruno'
1967 T120R - 'Caesar'
1968 Lightning - 'Dora'
1 member likes this: Magnetoman
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
Mañana came sooner than I might have predicted at sunset yesterday. This morning I printed my disassembly notes, numbered the steps, and proceeded to reassemble the gearbox in approximately the reverse order of those steps. It took an hour and 45 minutes from start to finish, but I stopped more than a dozen times to wash my hands in order to take photographs and make notes so my guess is it would have taken something like 30–45 minutes had I only worked on assembling it.

Assembling a Burman Q-Type Gearbox

1. Insert the sleeve gear.

2. Assemble the shifter indexing mechanism and insert the spring.

[Linked Image]

It will be difficult to assemble the rest of the shifter mechanism against the force of the spring so remove the cap from the bottom of the gearbox case to let the spring drop part way out.

[Linked Image]

[Linked Image]

3. Apply Permatex Permashield to the layshaft and hole in the outer case, allow 15 minutes for solvent to evaporate, and assemble the layshaft in the case.

[Linked Image]

4. Holding the main shaft and the layshaft gear clusters together, slide them as a unit through the bearing in the outer case and over the layshaft.

[Linked Image]

[to be continued]

1 member likes this: NYBSAGUY
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
5. Attach the inside kickstarter ratchet nut on the mainshaft and, holding the mainshaft in the soft jaws of a vise, tighten with a 1" BS socket to 150 ft.lbs.

[Linked Image]

6. Install the spring, outer ratchet piece, and nut and tighten with a ⅝" BS socket.

[Linked Image]

7. Make sure the bolt for the shifter mechanism is loosely installed from the inside before joining the cases. Apply Permatex Permashield to both cases, allow 15 minutes for solvent to evaporate, and tap the cases together. Having machined a lead-in taper in the bush for the layshaft that's in the main gearbox case will be found to be very useful at this point. After tightening the five external and two internal nuts that hold the cases together, make sure the mainshaft turns freely.

[Linked Image]

[Linked Image]

8. With the ball on the end of the shifter arm, maneuver the indexing assembly inside the gearbox to allow the ball to slip into the front of the recess for it.

[Linked Image]

[to be continued]

1 member likes this: NYBSAGUY
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
9. With the ball having been captured by the recess in the indexing assembly, maneuver the assembly to allow inserting the shaft on which it pivots. It may be necessary to move the gears to a different position to allow this. Insert the shaft through the hole in the other side of the gearbox case and secure it with a nut. Reattach the fastener at the bottom of the case that tensions the spring for the indexing assembly, and test to make sure the gearbox shifts through all three gears.

[Linked Image]

10. If you had removed it, press the shaft for the kickstarter back into the hole in the inside case. Install kickstarter spring in the correct orientation to tighten as the spring is rotated counterclockwise.

[Linked Image]

11. Insert kickstarter on shaft and catch the free end of the spring with the protrusion on the kickstarter. Getting the spring attached and having it clear the obstructions inside the case might take a little fiddling with positions. Once the kickstarter is attached to the spring rotate it approximately one-half turn counterclockwise to just past the 'stop' for it and then push it fully onto the shaft

[Linked Image]

12. Slip the stamped metal 'Burman' cover into place.

[Linked Image]

13. Other than the rectangular top cover, the round clutch actuating housing is the last piece to be attached. At this point align the projections on the inside and outside of the shifter mechanism and finish tightening the bolt that clamps the pieces together.

[Linked Image]

To have the measurements recorded:

Indexing spring:
31 turns
length: 3.27"
OD: 0.405"
ID: 0.26"
wire diameter 0.063"

Shifter ball:
OD: 0.559"
hole: 0.280" dia.

3 members like this: George Kaplan, Rudge00, NYBSAGUY
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
My notes show that three years ago I measured ~750 mL of Morris K400EP (NLGI consistency 00) as the amount needed to fill the gearbox to the recommended one-third level, to which at that time I added 50 mL 90W gear oil rated API GL1 as the equivalent to the "egg cup" of oil mentioned in the Ariel Manual. This time, with the gearbox better sealed than last time (knock wood...), I decided to increase the percentage of gear oil from the ~7% of an egg cup to more like 20%.

Having given the Permatex the better part of 24 hours to set, I placed the gearbox on a clean paper towel (in a baking pan with sides, just in case...), added 150 mL of Millers Classic Green Gear Oil[*] (which, despite its name, is pink, not green). That was enough to reach part way up the layshaft gears so, all by itself, it would be flung around to lubricate things. As long as it didn't leak out which, of course, this this time it won't... I then then poured in enough Morris K400EP to fill the case to what looks like somewhere between one-third and one-half full.

[*]SAE 90, API GL1, "Free of EP Additives, For Vintage Applications"

[Linked Image]

Once the K400EP starts moving it flows like molasses, light corn syrup or raw honey (to name the three items on the pantry shelf that I found to have similar viscosity), but once it stops moving, it stops moving, because it's a non-Newtonian fluid. The idea, highly flawed as it proved to be, of Burman using it rather than oil in the days prior to decent oil seals was that motion of the gears would make it fluid there, allowing it to lubricate the moving parts, but when thrown up against the walls of the gearbox case it would cease to flow and magically form a seal to keep the liquid in.

At least one flaw in the "self-sealing" idea was that the open nature of the bearing on the outboard end of the main shaft kept the grease churning, and hence fluid, allowing it to flow out via that route. However, with that open bearing now replaced with a sealed one, I can only hope additional flaws in the idea aren't revealed.

Joined: May 2019
Posts: 915
Likes: 336
C
Britbike forum member
Offline
Britbike forum member
C
Joined: May 2019
Posts: 915
Likes: 336
Have you used that Permatex much in the past? I haven’t managed convince myself to go paperless yet unless it came that way from the factory... in which case I normally use 3 Bond.
I may have been deep into one of those rabbit holes when you installed that bearing... is it sealed on both sides?

1 member likes this: Magnetoman
Joined: Sep 2004
Posts: 1,641
Likes: 138
Britbike forum member
Offline
Britbike forum member
Joined: Sep 2004
Posts: 1,641
Likes: 138
Well done MM, I think you've done a fantastic job of rebuilding the gearbox and documenting progress, we can only hope that the new sealed bearings, O rings and permatex work and that no leaks appear.

My only thoughts on the choice of grease and gear oil are as follows:-
- the Burman gearbox Manual suggests various greases as being suitable, including Shell soft and Castrolese medium. My assumption is that these are medium grade greases approx NLGI number 1 with an analogy of tomato paste, which is a bit thicker than the K400EP which is apple sauce according to This Link on Wikipedia
- adding additional Gear Oil will likely thin the mix even further and may cause leaks.
- the Burman Manual cautions against adding more than 1/3 grease as this will cause the gears to pump out any excess.

However, adding the new seals, bushes & bearings will now hopefully overcome the limitations of the original design, and the new greases and oil won't subsequently appear on the garage floor.


1968 A65 Firebird
1967 B44 Shooting Star
1972 Norton Commando
1 member likes this: Magnetoman
Joined: Nov 2012
Posts: 2,138
Likes: 69
K
Britbike forum member
Online Content
Britbike forum member
K
Joined: Nov 2012
Posts: 2,138
Likes: 69
"5. Attach the inside kickstarter ratchet nut on the mainshaft and, holding the mainshaft in the soft jaws of a vise, tighten with a 1" BS socket to 150 ft.lbs."

Was that nut really tightened to 150 ft.lbs? That is beyond any torque I've known in ordinary mechanics.

Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
Originally Posted by Cyborg
Have you used that Permatex much in the past? I haven’t managed convince myself to go paperless yet unless it came that way from the factory... in which case I normally use 3 Bond.
Permatex Permashield is the same as Hylomar, and my experience with it goes back at least five years. Over that time it completely lived up to the marketing materials:

Hylomar® is a polyester polyol–based compound that turns from a gel into flexible putty within minutes of application. ... Its non-hardening formula maintains seal integrity even when subjected to thermal distortion and vibration. ... impervious to oil, gasoline, glycol and other engine fluids. ... seals gaps .01" or less, and performs at constant temperatures up to 600 °F. ... components are assembled, reused and reassembled with ease. ... without a gasket or as a gasket dressing.

The claim to fame of Permatex Permashield is it remains flexible, whereas a sealant like Yamabond hardens so I suppose it could develop microcracks if the two pieces had some slight ability to move with respect to each other. The outboard end of the layshaft is a somewhat loose fit in the case, which is why I wanted something that could seal despite some small amount of movement.

Some years ago Dave-NV described his procedure for attaching primary gaskets in a way that allowed them to be reused. Basically, the gasket is "permanently" attached to the cover with something like 3 Bond (I use Yamabond 4), and sealed to the case with Permatex. I've used his process ever since, removing and replacing primary covers at least a few times, and it has worked great. But, only if you follow the directions and allow the solvent to evaporate for 15-20 minutes before clamping the pieces.

As far as I can tell the Burman parts list doesn't show a gasket between the inner and outer case. In any case, I used Permatex there three years ago without any sign of leak from that joint. However, I used Yamabond on the non-rotating bush in the case at the inboard end of the layshaft. I don't have a good reason (or even a bad reason) why I didn't use Permatex there.

Originally Posted by Cyborg
that bearing... is it sealed on both sides?
Yes. That doubles the odds of stopping -- or, at least, slowing -- the grease.

Originally Posted by gunner
- the Burman gearbox Manual suggests various greases as being suitable, including Shell soft and Castrolese medium. My assumption is that these are medium grade greases approx NLGI number 1 with an analogy of tomato paste, which is a bit thicker than the K400EP which is apple sauce according to
- adding additional Gear Oil will likely thin the mix even further and may cause leaks.
- the Burman manual cautions against adding more than 1/3 grease as this will cause the gears to pump out any excess.
I remember having spent a fair amount of time three years ago trying to determine the modern equivalents of those ancient greases. Although I don't remember the details, for forgotten reasons I ended up with NLGI 00. I can only infer that I was convinced of this because I went so far as to special order it from England since the U.S. importer of Morris products doesn't bring it into the country.

To the extent #1 grease would plug any remaining leakage paths, I expect #00 would do an equally good -- or bad -- job of the same (corn head grease is #0, and you saw how well that sealed...). The fact Ariel recommended adding an egg cup of oil makes me think the oil will stay separate, but it remains to be seen if the gear oil gets incorporated in the grease, thinning it, or remains separate and thus is even thinner and leakier.

Also, based on the fact Mobil 1 synthetic grease is #2, and is quite firm, I'm sure #1 would be too thick for the gearbox. The problem with heavy grease is the gears would cut a channel in it after which its firmness would keep it from flowing back to fill that channel, ending any possibility of it lubricating anything.

As far as I could tell, all the leakage was via that unsealed bearing that now has been replaced with a double-sealed one. In terms of managing my own expectations, we had to top up the gearbox with corn head grease every evening (i.e. ~250 miles). If that new bearing cuts the outflow rate to 10% of the Cannonball value, I'll be happy. If it cuts it even more than that, I'll be ecstatic.

The maintenance schedule I created three years ago says the clutch rollers need to be greased at 5000 miles. Even though there's only ~3500 miles on the Ariel it just wouldn't do to reassemble it without doing that.

I don't remember how I held the clutch basket then, but I decided I should make a special tool to hold it now. As the first photograph shows, the special tool I made simply consists of a length of ⅝" all-thread along with two nuts, two washers, and a ½"-long spacer I machined from a piece of scrap Al rod.

[Linked Image]

The second photograph shows the clutch basket being held in a vise, along with the 3-point sprag socket I had made for this purpose three years ago.

[Linked Image]

With the "nut" removed not a drop of grease is visible, so it's good I didn't wait another 1500 miles.

[Linked Image]

I greased the rollers with Mobil 1 synthetic grease, reassembled the basket, and set it aside for when I'm ready to work on the primary side.

When I removed the gearbox a few weeks ago I commented on the near-impossibility of removing the O-ring drive chain on the side of the road. Since I'd like to be able to fix a flat if it happens, I need a regular chain instead. At the time I had ground the heads from the rivets of the press-fit master link but still needed to remove it. As the next photograph shows, I ran into a problem when I tried to do that today.

[Linked Image]

The chain breaker is fully advanced in the photograph, with the pin from the master link peeking out, but that pin is still firmly held by the side plate, and in turn the pin firmly holds the chain breaker. As the next photograph shows, I cut a short length of ¼"-dia. steel rod to place between the threaded "pusher" and the hardened pin of the chain breaker, which added enough additional motion to drive the master link pin out.

[Linked Image]

Clearly, there's no way I could have removed that chain on the side of the road so it's a very good thing that I didn't have a flat tire on the Cannonball.

I also loosely bolted the gearbox back in the frame today, but I've used up my five-photograph allotment for this post so you'll have to close your eyes and imagine what it looks like.

1 member likes this: George Kaplan
Joined: May 2019
Posts: 915
Likes: 336
C
Britbike forum member
Offline
Britbike forum member
C
Joined: May 2019
Posts: 915
Likes: 336
Thanks for the info..

The bearings I’m using are sealed on both sides, but I can avoid having a debate with myself about removing the inner seal. They are NOS with emphasis on the O. The grease feels like it’s past it’s best before date, so will remove the inners and whatever crud is left in there. Curious to see what the cages are made out of anyway. Although... I suppose I could put them outside in the sweltering 28C heat and see if they limber up.

Last edited by Cyborg; 06/03/21 2:23 am.
1 member likes this: Magnetoman
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
Originally Posted by Cyborg
the sweltering 28C heat
I'll see your 28 and raise you 10. The forecast here for today and for each of the following nine days is 38–39. But, it's a dry heat...

Joined: Oct 2017
Posts: 495
Likes: 115
G
Britbike forum member
Offline
Britbike forum member
G
Joined: Oct 2017
Posts: 495
Likes: 115
Originally Posted by Magnetoman
But, it's a dry heat...


2 members like this: NYBSAGUY, Magnetoman
Joined: Oct 2017
Posts: 495
Likes: 115
G
Britbike forum member
Offline
Britbike forum member
G
Joined: Oct 2017
Posts: 495
Likes: 115
Originally Posted by Cyborg
Edit... or cheap as borscht from McMaster Carr.
Originally Posted by Magnetoman
............it flows like molasses, light corn syrup or raw honey (to name the three items on the pantry shelf that I found to have similar viscosity),
Originally Posted by gunner
....1 with an analogy of tomato paste, which is a bit thicker than the K400EP which is apple sauce according to This Link on Wikipedia
Maybe we should have a lubricant vs food viscosity equivelant thread? smile

John

2 members like this: gunner, Magnetoman
Joined: Oct 2017
Posts: 495
Likes: 115
G
Britbike forum member
Offline
Britbike forum member
G
Joined: Oct 2017
Posts: 495
Likes: 115
Great thread MM and great comments by all. Only just really catching up after being diverted away for a few weeks.

John

1 member likes this: Magnetoman
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
Originally Posted by George Kaplan
Great thread MM and great comments by all. Only just really catching up after being diverted away for a few weeks.
I see your supervisors have given you a temporary reprieve from mucking out stalls at your new hacienda de caballos. Enjoy your freedom while it lasts. I'm the on-call maintenance man for my daughter's horse trailer, having done the latest repair this afternoon, so your mucking will never end.

It was finally time to decide on the overall gearing I wanted. Those of you with long memories will remember that, based on me riding across half the State of Texas on my BB Gold Star the previous year at a steady 3000 rpm (=43% of redline = 50 mph on that bike), the engine feeling like it could run forever at that rpm, and the description of the speed our bikes would have to be capable of on the Cannonball, I geared the Ariel to result in 47.7 mph at 43% of redline. I was concerned before the start that the engine might not have the h.p. to handle gearing that high when we hit the Rocky Mountains so brought a smaller sprocket, just in case, but I remember only once having to drop back to 2nd for maybe a mile on one steep segment.

So, given the above, it took about 2 seconds of weighing the important factors in my gearing decision (specifically, I live in the wide open spaces of the Southwest, albeit with significant mountains as well, and I don't plan to commute on the bike in city traffic) to decide to use the same high gearing. So, as the first photograph shows, today I (re)installed the 22T gear on the gearbox.

[Linked Image]

I used my battery-powered impact driver to tighten the nut so if the manufacturer's specs are to be believed, that's 220 ft.lbs.

As the second photograph shows, this particular gear requires a 0.82" spacer between it and the sleeve gear bearing to align it with the rear wheel sprocket.

[Linked Image]

The 19T gearbox gear I am not using has this spacer as part of the gear. I already had (re)installed the 23T sprocket on the engine.

[Linked Image]

With this gearing redline is at 111.29 mph, so when I decide to take it to Bonneville I will need even larger sprockets. However, for now, the 23T/22T sprocket combination should do nicely for Gold Star/pre-Gold Star rides in the Southwest.

1 member likes this: George Kaplan
Joined: Nov 2016
Posts: 291
Likes: 85
N
Britbike forum member
Offline
Britbike forum member
N
Joined: Nov 2016
Posts: 291
Likes: 85
Count me in for those rides, MMan.

Having done three short flights to and from Boston in the last month or so, I feel I am, ahem, geared up for a red eye to Tucson, AZ.

1 member likes this: Magnetoman
Joined: Oct 2017
Posts: 495
Likes: 115
G
Britbike forum member
Offline
Britbike forum member
G
Joined: Oct 2017
Posts: 495
Likes: 115
Originally Posted by Magnetoman
I see your supervisors have given you a temporary reprieve from mucking out stalls at your new hacienda de caballos. Enjoy your freedom while it lasts. I'm the on-call maintenance man for my daughter's horse trailer, having done the latest repair this afternoon, so your mucking will never end.
Thanks MM. You guessed correctly, i.e. it is "temporary" reprieve. Hopefully all of the urgent (to my supervisors) equestrian related tasks should be taken care of in the next 3 or 4 weeks. I suffer from the same affliction as you, we are both very capable at fixing stuff so rather than call a tradesman, our Supervisors come to us.

Originally Posted by Magnetoman
It was finally time to decide on the overall gearing I wanted.
I remember thinking at the start of this redux (when you mentioned gearing) that the gearing that you reported on during the Cannonball seemed to be ok.

John.

1 member likes this: Magnetoman
Joined: May 2019
Posts: 915
Likes: 336
C
Britbike forum member
Offline
Britbike forum member
C
Joined: May 2019
Posts: 915
Likes: 336
Originally Posted by NYBSAGUY
Count me in for those rides, MMan.

Having done three short flights to and from Boston in the last month or so, I feel I am, ahem, geared up for a red eye to Tucson, AZ.

What in hells half acre would possess you to fly across the country so you can rattle along the highway in +40C heat?

2 members like this: NYBSAGUY, Magnetoman
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
Originally Posted by NYBSAGUY
Count me in for those rides, MMan.
Duly counted in.

Originally Posted by Cyborg
What in hells half acre would possess you to fly across the country so you can rattle along the highway in +40C heat?
For the pleasure of my company? OK, that can't be it, so there must be another explanation. Oh, I know what it is, he realizes I equipped a trailer specifically to extend the riding season to a full 12 months, and he correctly assumes I'll use it to haul the bikes to higher, cooler altitudes for any such rides during the summer months. Picking a location at random, while for the next week the high temperatures near me will be ~100 ℉ (38–39 ℃), Flagstaff will be 76–82 ℉ (24–28 ℃).

Originally Posted by George Kaplan
I remember thinking at the start of this redux (when you mentioned gearing) that the gearing that you reported on during the Cannonball seemed to be ok.
Actually, when I gave it serious thought (which took all of a few seconds), I realized the gearing was as close to perfect for my uses as I could hope for from a 3-speed gearbox.

1 member likes this: NYBSAGUY
Joined: Nov 2011
Posts: 7,193
Likes: 401
Britbike forum member
OP Offline
Britbike forum member
Joined: Nov 2011
Posts: 7,193
Likes: 401
My infallible system of placing parts in muffin tins and trays when I remove them inexplicably failed me. The nut that holds the clutch basket on the gearbox shaft was nowhere to be found. Unfortunately, my drawer of "large Whitworth nuts" has nuts that are either too large or too small. So, I had no choice but to spend the time to make a new one in order for the lost one to suddenly appear.

Rather than starting from raw stock, a ½" wheel lug nut has plenty of material to work with. The first photograph shows it in the process of having the ID enlarged to the tap drill size for ⅝"-20 Unified Extra Fine (UNEF).

[Linked Image]

UNEF are the taps I have in my "Whitworth" tap & die drawer pretending to be proper British threads in 20 pitch for sizes larger than ½". Because all of these are bottom taps I was afraid I would have difficulty cutting new threads but, as the next photograph shows, there wasn't a problem.

[Linked Image]

I started with the tap in the tailstock chuck, turning the main chuck with the key until I was sure the tap was cutting straight, then finished with a tap wrench.

After I finished cutting the new threads I tested the nut on the gearbox shaft. It took 5 ft.lbs. to turn the nut onto the shaft the first time, after which it took 2 ft.lbs. to remove it. After that initial try to get the threads acquainted with each other, I could thread the nut on by hand. It doesn't spin on, but my fingers exert enough torque to turn it.

After I had confirmed the nut was good, the next photograph shows I removed some of the excess length to make sure it didn't interfere with the top "pressure plate" when the clutch was assembled.

[Linked Image]

Since it appears that maybe not too many threads are engaging, I removed the nut after firmly tightening the hub onto the taper and found 5 exposed threads.

[Linked Image]

There actually are only ~6 threads on the end of the shaft so the nut has done all that has been asked of it. The final photograph is from when I disassembled the clutch a month ago.

[Linked Image]

As this final photograph shows, the end of the shaft also was recessed inside missing nut (which was thinner than the one I made today).

My home-made chart of torque figures extracted from workshop manuals shows a "½" clutch center nut" at 60/65 ft.lbs. I decided to treat the Ariel to 55.

I ended the day with a mystery. Despite having spent that time to make a new nut, the original one still hasn't reappeared. I'm at a loss for a rational explanation for this.

2 members like this: NYBSAGUY, Stuart Kirk
Joined: Feb 2019
Posts: 520
Likes: 216
S
Britbike forum member
Offline
Britbike forum member
S
Joined: Feb 2019
Posts: 520
Likes: 216
Originally Posted by Magnetoman
I started with the tap in the tailstock chuck, turning the main chuck with the key until I was sure the tap was cutting straight, then finished with a tap wrench
That is such a good strategy. I do it that way all the time.

Right up there with drilling and tapping a guide block in the mill or drill press for use starting taps nice and straight and for ensuring that each thread is a good one.

1 member likes this: Magnetoman
Joined: May 2019
Posts: 915
Likes: 336
C
Britbike forum member
Offline
Britbike forum member
C
Joined: May 2019
Posts: 915
Likes: 336
Good thing it’s about 2C per 1,000.... you can probably find a butte that’ll get it down to a civilized level.

[Linked Image from live.staticflickr.com]92C684EE-E509-42FA-933D-1A749230CC0A by First Last, on Flickr

1 member likes this: Magnetoman
Page 125 of 133 1 2 123 124 125 126 127 132 133

Link Copied to Clipboard
Job CycleBritish Cycle SupplyMorries PlaceKlempf British PartsPodtronicVintage MagazineBSA Unit SinglesBritBike SponsorBritish Tools & FastenersBritBike SponsorBritBike Sponsor






© 1996-2021 britbike.com
Powered by UBB.threads™ PHP Forum Software 7.7.5