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Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555006 07/26/14 1:53 pm
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Hi Allan

I originally experimented with 0.006" & 0.008" based on looking at other engines with alloy barrels. Then Mark P posted more information based on his long experience with his alloy barrel, which gave me the confidence to go down to 0.004" & 0.006" using standard push rods and its running good. Sorry nothing scientific or any fancy formulae to get you excited.
As Mark said using c/molly rods his running more or less zero clearance, which was the case with later racing Goldstar and Velocette engines. There's not actually a lot new going on, just a matter of updating to the use of modern materials and technology.

regards

John

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Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555030 07/26/14 4:25 pm
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A look at the manual shows that the rodents had chewed the feed to the coils on the white yellow core from the RHS handle bar switch, will check the continuity/ resistance with a meter.

The heat has gone and the rain is back, Burlens 6-7 week delay is a scunner, may try Surrey Cycles, they have some nice carb stuff, brass slides and the like.


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555113 07/27/14 4:21 am
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I have used Surrey Cycles and always got good service, Hitchcocks is another option as they do the AMAL range too.

Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555190 07/27/14 4:27 pm
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Spoke to the nice man at Surrey Cycles, carb stuff goes in the post Monday.
I should get some time in the shop tomorrow, pipes and cables time.

Some filler details,
rear wheel , swingarm bearings, checked OK.
Cleaned out light rust from the rear drum, life in the old shoes yet.

I may have to splice some new wire in for the ignition feed.

The motor turns over well and has healthy but not massive compression. Will put a gauge on later. Hoping for about 130 psi.

Must order oil, I use Silkolene chatsworth 40, having seen how clean and un-scuffed the old pistons were Im sticking with it.


Last edited by gavin eisler; 07/27/14 4:36 pm.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555195 07/27/14 5:25 pm
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Hi Allan
sorry for the late reply
you asked

"I'm interested at how the figures Gavin stated came about, was a height measurement taken from a cold and another from one at full operating temperature?"

I have , in the past messed about, getting the motor hot then checking, it was the old set up tho, I have tried closing them in from stock, it was so long ago I didnt take notes, but I ended up back at 8 and 10, ( more worried about burning a valve seat than anything else).
As I understand it the extra expansion of the block means slightly closer settings are safe to use.


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555346 07/28/14 2:12 pm
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Back having a look at the wires, checking resistances,

[Linked Image]

the meter zero is o.9 ohms

[Linked Image]

, its on the 0 -200 ohm scale, a close look at the stop switch block contacts

[Linked Image]
[Linked Image]

Checking feed wire at the Boyer end up to the stop switch
[Linked Image]


Here we see dimensional instability in action, this fitted OK before I took it off

[Linked Image]

Silicon in the ports
[Linked Image]

[Linked Image]

Pipes are on
[Linked Image]


[Linked Image]

Ians bead breaker in action on the front wheel

[Linked Image]

New brake switch. ( They never last long)

[Linked Image]

Nipped the tube, will refit tomorrow after repair
[Linked Image]

Thats all for now



71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555559 07/29/14 2:19 pm
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Front wheel has a dodgy bearing, . N6204 , might have them at work.

[Linked Image]

Assorted float bowl gaskets, no real turkeys, they all passed the float bowl gasket test. Steves Brit gasket item is very well made, sadly I dont have a pair so I am staying with the fresh AMAL branded gaskets. They fitted well, not perfect but good enough.

[Linked Image]

Carb parts came today, nice brass slides, new 106 NJs , matching needles , fresh viton tipped float needle valves.
The old MJs are going in, they dont wear so much as get varnished up.

[Linked Image]

Slides are heavier built than the alloy ones. Old one on the left.Whew, the new slides are a good fit , none of the previous rattle, nicely made.

[Linked Image]

LHS slide was a wee bit tight near the bottom,

Scrubbed out the carb with acetone to clean the bottom section.


Throttle twist grip assembly, some new bits, replacement stop screw and friction damper, these were missing before , its a Tomaseli Daytona -2C, got the spares from Bevel Heaven. This was on the bike when I got , but these bits were missing.This means the cables are non stock.

[Linked Image]

Fitted new fuel pipes

[Linked Image]

made up a throttle cable, cut to length and mushed the end up.
The BSA generates its own tools, the musher ( not shown , thats a centre punch which I used initially to fan the cable end in the nipple bowl.) is the old spoke from the rear wheel ground to a rounded end, Ive used it for various poking jobs, good tool . The last pic is after using the musher.

[Linked Image][Linked Image][Linked Image][Linked Image][Linked Image][Linked Image]

Working, ahhh new cables, what a "must have".
Still to do the RHS

[Linked Image]

Shortened this throttle stop screw. The throttle could only pull about 32 mm max, so I shortened it by about a half inch so it didnt stick out too much.

[Linked Image]

Overview,
Cable runs need adjusting, will take the cables round the front of the lamp for an easier bend.

[Linked Image]


Shortened the carb mount bolts and ditched the flange gasket.
I need all the space I can get so the fuel balance pipe stops saying hello to the airbox. I have nipped up the flange bolts so that the allen screws can still turn with a bit of effort, this would be a good place for Alloy bolts or even plastic!

This bike wears Allen SHC screws , they make maintenance a lot easier, no chewed screws, everything has come apart with a positive grip. I know you can over-tighten them , but using the key with the short end to hand stops any over-torquing, it works for me.
A lot of the fasteners were sourced from various mega firms in Dundee , Ferrantis, Holo Krome and NCR ( The Cash) where I knew apprentices back in the day. The Stainless shock mount bolts were from Carolina Port B power station, ( Oil fired 2 x 120 MW AEI turbines ) I was apprenticed there.



Last edited by gavin eisler; 07/30/14 4:58 pm.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #555648 07/30/14 4:32 am
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Had a good look at the front wheel, changed both bearings,
[Linked Image]

the central cavity had trapped a lot of water, partly ( I think ) because the sealed bearings ( which had only done a couple of thousand miles)allow vapour in , then it condenses/ gathers, also they were gubbed, the drive side had been dragging on the wheel spindle, a few thous of wear means its not a good fit any more.
New spindle time, or machine down and sleeve, for now its getting bearing fit .
The central cavity was coated in rusty mung.

It all spins well now on the new bearings but the spindle is a "must do soon".

The brake drum cleaned out ok, used 180 grit 3 M production paper, there is some ridging near the inner part of the drum, grit no doubt , the shoes are healthy and match the grooving, its going back as is., I might try and source some longer cam arms. The shoes were fresh in 2002. As were the bearings . hmmmm...

[Linked Image]

If any one reading this has any experience of the longer brake cam lever arms can they let me know, good/ bad/ drawbacks ?.
I am concerned that the bars lever will run out of pull with longer cam arms.


The "comical " hub has a rep, I am sort of OK with it, twin discs are a whole lot better, but this one works surprisingly well if you squeeze it to the point twin discs would be locking up.
Before I fitted the heavy cable it was fair to poor, with the cable its , good to OK.


I will show brake cable shots later, the cable as found is in good condition, its very heavy , both inner and outer, with no switch., I have a new spare with a switch , for the brake light , to compare.

[Linked Image][Linked Image][Linked Image][Linked Image][Linked Image]

The fork stanchions are straight and the rubber shrouds have protected the travelling seals area.
In an ideal world , I would prefer new stanchions just for the cosmetics, the upper chrome is fly blowm.
The lower slider need rebushed, the upper forward zone of the RHS slider is badly worn. Maybe an overwinter holiday at Maxton would be a good thing.
I would like the forks shortened, losing an inch or two of travel would be no great loss, it doesnt really need 5 ", and shorter would be stiffer .

Complete twist grip
[Linked Image]

Complete throttle cables
[Linked Image]

Hooked up choke cables
[Linked Image]

For now its getting an oil change and polish.

Still have to mend the front tyre nip.
Will try the LBS for a 19" tube. Result.

Throttles feel sweet , got the routing sorted.
Tyre fitting, ( 3rd attempt) tomorrow. I may slaughter a warm blooded creature to appease the tube gods.
Cheers for now




Last edited by gavin eisler; 07/30/14 5:06 pm.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #556130 08/01/14 7:42 pm
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Sorted the front tyre, new tube fitted, I had managed to nip the old one four times, I think this was when it was removed with the old tyre, my friend who was helping is young and was unaware of tubes, any way its mounted.

Fitted the front wheel, and had a set back , the torque mount stud female thread in the brake plate is stripped , 3/8 " x 16 tpi, this will get a helicoil repair,but its Friday and bits wont be here till next week, oh well , never mind.

[Linked Image]


Trial fitted the tank with all cables and pipes, no major conflicts, hurray, the reserve tap has lost its filter, and both taps are gummy from fuel, they are getting an over night dip in the rhubarb.
[Linked Image]
[Linked Image][Linked Image]

[Linked Image]
[Linked Image]

Before rubbing with Al foil
[Linked Image]

After

[Linked Image]

Must find some suitable washers to reseal the taps.

[Linked Image]

These old school taper 1/4 turn pet cock/ fuel taps are a big step up from the old push pull cork plunger types. Because of the carb stubs the old push pulls have conflicts .
I found these in a drawer full of carb stuff a bout 12 years ago, Im keeping them , they should clean up OK, need to solder in a new filter as well.

Drained 1.4 litres ( about 3 pints ) from the sump.

[Linked Image]


Put a fresh battery in, lights all work, foot brake switch works, horn doesnt work ( the vibration will fix this, its done that before.) Sparks were a bit meagre.

[Linked Image]

Remade all coil connections removing the Boyer crimps that John Healy doesnt like, they were a bit loose at the terminals. The new crimps are made with better pliers.

[Linked Image]

So the 11 year old Boyer , 30 year old HT leads and 40 + year old coils work, quell surprise.


Kicking it over with the sump drained and plugs in it feels very crisp.

Getting there ,

[Linked Image]





Last edited by gavin eisler; 08/01/14 7:57 pm.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #556217 08/02/14 10:12 am
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Fuel valves, pet cocks, gas taps, who knows
after a dip, with donor filter to be soldered in.

[Linked Image]

The old ignition switch with keys , showing drilled out rivets replaced with screws and nuts.

One of the old contacts was so far gone I had to replace it with a brass screw
[Linked Image]

Its hard to beleive all those mighty Lucas electrons are meant to pass through this, Im posting it as an achilles heel look out for other people trying to fix their old mounts.

[Linked Image][Linked Image]

This is not the switch currently fitted , I looked it out when searching for the key.


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #556262 08/02/14 3:40 pm
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Hi Gavin,
great story like always, congrats smile.
To write about bike reno and make it interesting needs some talent, I'm sure.
I too swapped my former Lucas connectors with metal crimps + plastic covers sold separately giving me better crimping ability. Only problem is the quality of the metal connectors, sometimes they are so thin they last couple years on my BSA.

Going back to petcocks, what is the method of sealing yours ?
I still fight my push pull ones with some success lately.

Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #556276 08/02/14 5:44 pm
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Hi Adam,
Thanks for the kind remarks, I am in the middle of refurbing my fuel taps right now , I have one close by which needs a filter refit. ,
I have 1/4 turn taper cocks fitted, they got an overnight dip in the Oxalic acid, then stripped down,

[Linked Image]

the moving taper was lapped in with brasso and the spring was cleaned in phosphoric acid, rust eater,

[Linked Image]

after cleaning with polish I wiped it clean and lubed the taper with soap before re assembly .

[Linked Image]
\it went back together well and feels very nice to use now.


I dipped the filter in a mix of malt vinegar a sodium percarbonate, it frothed up well.

[Linked Image]

After a twenty minute dip in the can

[Linked Image]
Showing the 4000 year old flint scraper that came with the brass service bowl.

Last edited by gavin eisler; 08/03/14 5:50 am.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #556750 08/05/14 1:47 am
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Some delays caused by life getting in the way,

While I wait for the helicoil kit to repair the front brake plate , I thought I would strip it and re lube.
The red pointer is on the stripped hole

[Linked Image]

[Linked Image]

Rivetted shoes

[Linked Image]

Operating arm as found, some grease some water

[Linked Image]

Showing water damge to bearing surface before cleaning

[Linked Image]

[Linked Image]

[Linked Image]

After rubbing with Al foil

[Linked Image]

Cleaned parts, the brake plate got a swift rub down and blow over with matt black heat paint.

[Linked Image]

T^he fuel filter is repaired , will head over to the bike on Thursday, hopefully.
Im runninhg out of jobs to do.

Fork oil change , but I may get it going first.
Cheers
GE






71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557053 08/06/14 3:36 pm
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Back in the underground layer
with helicoil kit

9.9 mm just took out dust and a few shavings

[Linked Image]


Tapped for helicoil

[Linked Image]

Coil in
[Linked Image]

A ten minute job if you have the gear, helicoils are great!

Rebuilt using a dab of grease here and there
I have been using this grease tin since 1974, good value, its nearly empty though.

The hub lever system is well engineered , the micram adjusters are set for max clearance on re assembly, these will be set when the wheel is installed.The piston cam followers and lever spindles are neatly sealed with O rings, a nice touch to keep the brake clean, the micram adjusters just get a suggestion of grease to prevent corrosion more than anything.The shoes are about a quarter worn , they worked well before and are going back in.
The shoes went back on without drawing blood, assembled all bar one spring, then fitted on, fitted the 2nd spring with the shoes lifted at the sides, popped on easy.

[Linked Image]

A ceilidh with AA in the control room, he is a fellow beesa ( 68 Thunderbolt, with original pipes) owner and all-round good guy.

[Linked Image]

Wheel on tomorrow.

Last edited by gavin eisler; 08/06/14 3:47 pm.

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557232 08/07/14 1:46 pm
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It runs, fuelled up with 98 ron , cured a couple of minor leaks, loose float bowm and banjo RHS.

Kicked over with choke and tickling, running steady after 3 kicks. Took it for a run, needles were too lean, loads of spitting when accelerating.
Next run, raised one notch , better but running on LHS only, RHS needle was out of its clip. next run better but lumpy. synched carbs, next run very nice.
The motor is crisper , higher comp than before, pulls very well from 3,000 ( on the smiths instrument which still works ) , had it up to 5 K briefly , pulling great.
I am cock - a - hoop.

Only leak at the pipes was a small hole on the RHS header , plugged up with anwee screw.
Out in the sun.

[Linked Image]
[Linked Image][Linked Image]

My son has a go pro, once its leagal and dialled in, ( tickover is still to be fully sorted)
I will go for sound and movement.
Its been a blast .
GE



71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557233 08/07/14 1:48 pm
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Ger B Offline
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Well done! :bigt

Does the brake work as you expected?


Ger B

Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557350 08/08/14 3:17 am
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Thanks Ger

The brake woyks as expected. It takes a good squeeze , unlike a modern twin disc.

I had forgotten how sweet the handling is, I like the big wheels compared to the wee doughnuts
fitted to modern bikes.

The weather is back to rain here and I am on night shifts. Will book its MOT for next week.
Cheers
GE


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557371 08/08/14 5:54 am
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Ger B Offline
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Quote
It takes a good squeeze, unlike a modern twin disc.

I'm always surprised when I get off the Hinkley Trophy onto the A65T and vice versa.

Enjoy.


Ger B

Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557396 08/08/14 9:51 am
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Looks great, Gavin.
I had to make very quick decarbonisation of my A65 head as well.
Putting it back together tomorrow.

Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557402 08/08/14 10:41 am
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Its never over over or easy.
Ordered some no.78 drills and 2 BA taps for cleaning the pilot jets, I am not convinced they are metering properly.
Still to do.
Fix the horn, fit cycle speedo for MOT, Have a decent run, re-torque head , take compression pressure readings. Change oil all round. Later, send forks to Maxton.

Its been a fun rebuild.

Many thanks to the following in no particular order.

John Hill,alloy barrel creator, he has been following this thread closely and offering advice and information when needed.

Ian Shellcock, for the use of workshop space and copious cups of tea.

Tony Salmon , the friendly welder at work.

My family, for putting up with me in Beesa rebuild mode ( must stay focussed).


General impressions, after a couple of test rides.

The 21 / 47 gearing feels about right, the motor is happy at 4k on a very low throttle opeming.
The carb mixture settings need reviewed. The higher comp motor may need more main jet, it certainly needed the needles raising , although the needles were probably on the top notch to compensate for wear on the old carbs. The pilot mixture seems happier with the adjuster screws at less than one turn out , hence the n0. 78 drill order.
The controls are sweet, any extra noise from the alloy barrel is compensated for by the tighter clearances for pistons and valves, its certainly no noisier.
The bathroom tile silicon left overs used for the zorst pipes works very well, no leaks.

In seven years the bike will be 50 years old, it may get a celebratory paint job.
Cheers
GE





71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557411 08/08/14 11:46 am
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Gavin,
Just some thoughts;

Years ago, when the small cc mx'ers started going to the really large cooling fins, trying to dissipate the large amount of heat the high horse power engines were putting out, before serious efforts at water cooling came about, several of the manufacturers started putting small .. rubber? discs between the fins, to dampen the singing fins' vibrations.

I think Yam and Suzi even at one short point, used a strip of rubber blocks along the outside of the fins???

You might try to find some high density rubber blocks or discs to place between your cylinder fins? Maybe bits from some old tire? Especially an off road heavy lug tire...

I think they found that if the rubber fits snugly enough, you don't need to put one between each fin, just alternate fins? So that each fin touches the rubber?

......... Maybe [ never tried this myself ], if you find long enough blocks, you might try to angle the blocks to try, TRY!, to 'duct' air further into the ... throat? depth of the fins, to get better cooling???

Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557417 08/08/14 12:42 pm
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@Rickman, I have some MZ 250 barrel rubbers, they may get a try.
Cheers
GE


71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557800 08/11/14 8:47 am
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Heh, Gavin,
Had a brain joggle this weekend!

I don't know about your area, but along the freeway, there is way too often a strip/chunk of shreadded re-cap tire from some underinflated semi-truck tire.

There is your useable, cut-to-size as often as you need, heavy, thick, compounded rubber!

Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #557971 08/12/14 9:13 am
Joined: Aug 2001
Posts: 4,783
gavin eisler Offline OP
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OP Offline
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Joined: Aug 2001
Posts: 4,783
Theres no free way for about 100 miles where I stay, but we still get truck blow outs so there
are plenty of roadside donors, nice idea.

While Ive been back at work the postman has done his thing and delivered the following from Chronos tools
.

The "Model Engineers Yearbook "

[Linked Image]

is a must have for useful info.
Eg. co efficient of expansion for alloy =0.0255 /degC , irom,=0.0102 perdegC dural =0.0226 . hence alloy expands nearly twice as much as iron, so push rod tappet settings may be halved. My old copy went missing at work.
As a reference its more comprehensive than Zeus books. Its not often I buy the same book twice, but for me this is a must have.

The wee drills are for clearing the carb pilot jets , no78 s or 16 thou.

[Linked Image]

They are the tiny packet ( 10 of ) between the taps.
The carbs are getting a revisit, float levels will be set to 60 though below lip and 2BA taps are present to create cleaning plug holes opposite the pilot jets as per the Bushman site article.



71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: alloy barrels for 750 OIF 1971 [Re: gavin eisler] #559038 08/19/14 4:57 pm
Joined: Aug 2001
Posts: 4,783
gavin eisler Offline OP
BritBike Forum member
OP Offline
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Joined: Aug 2001
Posts: 4,783
Oh frabjous day, calloo callay.

Finished a wearing set of shifts, , Ive been through the carbs,
created the pilot jet drill tool . Checked the float level per J Healy, and the Bushman site, they were both fine , about 60 thou below the bowl face when pushing down the float tangs, no fannying needed.
Theres the no. 78 drill on the tweezers

[Linked Image]

Theres the plastic tube which will allow me to handle the drill

[Linked Image]


The drill glued and squeezed into place

[Linked Image]



I turned my back on the lightning and this thing nicked its bench space, its got 2 too many cylinders.

[Linked Image]


RHS pressure readings, carbs dismounted, 140 psi after about a dozen kicks.

[Linked Image]

LH cylinder readings after ten kicks ( foot getting sore) 120 psi

[Linked Image]

Will take more readings after the bores have settled in.

No more pics but plenty to tell.
Today had mixed results.

With the pilot jets cleaned out with the no 78 drill, things steadied up at the idle end , and the pilot air screws settled down at more like 1 and 3/4 turns out.
The first run was a bit of a disappointment, attempts to stabilise each cylinder idle settings showed they were well out of whack.
Off with the tank, pulled the slides, the LHS had the needle dislodged, my bad for not wearing glasses when reassembling.
Put it right . Fixed the horn, it was just needing some TLC , it came back to life after cleaning the terminals and checking volts were going to the correct places.

Brimmed the tank, sadly there is a fuel leak from a pinhole above the LH fuel cock at the top of the tunnel. Fixable but a pain in the backside with the MOT coming up.

Next run with a bare gallon on board, carbs synched at WFO and full shut, pilot screws at 1 AND 3/4 TURNS OUT.
Result, bike runs properly, a sedate run out to a private spot, , slight tweaks to the carbs, a 1/2 turn in on each pilot screw and a 1/2 turn lower on each throttle stop, now we are talking, no fluffs, no spitting, clean pickup, steady idle.

Took it to 5K in 1st , 2nd and 3rd. What a great sound, a proverbial tearing of calico.

Ive found some pairs of larger main jets, 240s and 250s. Will try them next.

New rubber feels good.

Its a shame about the tank, there is a good local welder in Oban , Figgsie, he will be getting a visit soon.
Cheers
Pod





71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
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