The Clutch on my Comet

nkt267

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I saw something on another site for bikes with Burman clutches.they advise running the clutch case DRY:eek: and using spray chain grease on the primary chain, to stop the plates sticking.A reference to the Marston Sunbeam parts list for 1932 suggests no lubrication in the primary if Ferodo inserts are used.Does this suggest that non cork material might be prone to sticking if they are lubricated with oil (wrong oil?) The set of plates I replaced after the Manx showed that oil had got on to them via the drive side mains and they were a mess. The noisy gear change was caused by that and, as Tom says, the basket had cracked and spread to such an extent the top plate tang had jammed between 2 slots on the basket.Pulling away was almost as exciting as Charlie Boorman's wheelies(nearly lost the wife once):D.
The other part of the clutch mechanism that seems to be overlooked is the operating arm in the case.If the small halfmoon section that bears on the rod pin is worn away then you get less lift as well..John
 

Len Matthews

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This business of clutch plates sticking together after a period is nothing new. I recall a Comet where the plates were stuck solid even after a relatively short spell of idleness. The problem stemmed from the grade of friction material. Once these plates were changed for a set supplied by one of our leading spares suppliers the difficulty diappeared and crunchy 1st gear engagement became just a memory.
 

Tom Gaynor

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Clutches

I've had no problems with the V3 except for the first "clutch operation" of the day, and that includes runs including about 2 miles of threading traffic. I know (because I looked at the lift issue when trying to cure what I now think is stiction) that my 1951 52,000 mile twin has about 3/32" of lift with what I am sure are the original parts.
I have a friend who cured oil leaking out of a Rudge chaincase, but not before it had leaked into the (dry) clutch by draining the case, cleaning the clutch, and using chain lube spray thereafter, and I have done that myself. I'd be leery however about trying it on a twin, or even a Comet used for long runs. I've read that the chaincase oil plays a significant part in dissipating heat from the chain, and find the argument persuasive. I therefore bit the bullet, cured the leaks both out of the chaincase and into the clutch, and the Rudge runs on oil.
Stuart Towner offers a "wet or dry" Rudge clutch conversion so perhaps any day now he'll stagger blinking from all that midnight oil smoke out of his laboratory with a similar Comet conversion........
 

clevtrev

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The other part of the clutch mechanism that seems to be overlooked is the operating arm in the case.If the small halfmoon section that bears on the rod pin is worn away then you get less lift as well..John
That`s why there`s an adjuster on the cover.
 

tim welsh

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This also happened to me just before the clutch basket did the "splits", same as Pete's, so it would be worth checking- I think you can see the basket well enough through the filler cap. See my thread "Burman Clutch". Most recommended the Conways replacement if that is the problem. I've run it in ATF for a couple of years now with no sticking problems.
Tim
 
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dave g6xnc

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Clutchs.

An old dodge before starting the bike pull in the clutch and kick it over a few times, this will of course free up the cluth plates. If it tries to turn the engine over with the clutch out you have got problems.
dave gs.
 

Tom Gaynor

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Clutch problems

Before I changed the oil in the chaincase to Mobil1 I could easily start the bike (a twin) with the clutch pulled in. If I did get the clutch to unstick by kicking, it STILL went into first with a hellish crunch. So I really had a problem.......
 

Tom Gaynor

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Clutches on old bikes

I think Fraser has hit the spot. A conclusion I came to after going from close ratio boxes to road ratio boxes was that road bikes before, say, the 50's were intended to be ridden in top, with the other three gears used for getting to top, or for extreme conditions - steep hills or heavy traffic. I therefore adjusted my attitude, and stopped trying to make lighting changes, "flicking it down one" because the ratios were too far apart anyway. The contrast between my Norton with a six-speed Shaffleitner, and, say, the Vincent, is stark. The Shadow has a very nice high first, which means I don't have to come to a virtual stop before engaging it as I do with another (1938) bike. But changing gear on the Vin is a three step process, whereas with a six-speeder I just press the pedal, clutch optional.
 
G

Graham Smith

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Anyone who knows me will tell you that I'm not the most mechanically minded person in the world, but I'm willing to give most things a go.

On my Comet, whenever I put it in gear, it's a real 'crunch' of a gear change. Likewise, when going from 1st to 2nd, the same thing.

From 2nd to 3rd OK and 3rd to 4th OK.

I've tried adjusting it, but that doesn't seem to make any difference.

Someone has suggested that the clutch plates could be getting stuck together, but this is now getting out of my capabilities.

Does anyone have any other suggestions on what I can do to make a nice quiet/smooth gear change?

My Executive Committee colleague and thoroughly good bloke Dick Wheeldon kindly agreed to have a look at my Comet's clutch, and we discovered there weren't enough friction plates!

Apart from that, we took the other friction plates and gave them a good clean in white spirit, as they were completely stuck together. They seem fine now.

I'm planning on going out for a spin tomorrow, so if anyone sees a Comet broken down at the side of the road in the Orpington area, please stop and offer me some assistance!:)
 
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