Clutch?

pssnook

New Forum User
Non-VOC Member
New member, new owner of vincent comet, I have always had modern bikes circa 1990>. I have a father in law with old BSA's and the like and enjoy borrowing them for rides etc and decided to join the ownership side of things.
I bought a non running 51 comet. No spark so magneto taken off and new BTH mag fitted, now I have a strong spark but when trying to kick over the bike it seems that the clutch is slipping? I have checked the clutch and all pressure plates look good with no distortion and the clutch plates seem healthy, I have used brake cleaner on them to take off sheen and gently rubbed with emery paper to try to discourage slippage to no real advantage. Could it be the kick start teeth? I dont think so but obviously I am not in my comfort zone with the old boy.
Anyway I think this is going to be a regular place to vent my woes and hopefully joys so I will sign out..
 

Len Matthews

Well Known and Active Forum User
VOC Member
Unlikely to be kick start teeth. One possibility is stripped splines in the clutch centre. No doubt you've checked for clearance on the clutch push rod; remove the gearbox filler cap and ensure there is a little free movement on the arm where the cable is attached; if not, that could be the problem.
 

nkt267

Well Known and Active Forum User
VOC Member
pssnook
Member of the Vincent H.R.D. Owners Club
Non-Member of the Vincent H.R.D. Owners Club
Now how did our system get you as member and non-member at the same time? Is this a record?.
Len's advice is sound either the clutch is slipping because it is poorly adjusted or the springs are not screwed down enough. I hope the centre is not stripped but thet are easy to change and are available. Be aware though that clutches can be 3 or 4 or 5 plate versions, the Comet should be 5 plate and the clutch centres are different depths to accommodate this. It's not unknown for an AJS clutch to end up on a Comet. If you end up going the route of a Conways clutch mod then I can confirm that they are very good, I have one on my bike and have fitted one to my nephews Comet..John
 

pssnook

New Forum User
Non-VOC Member
Hi Len, I have now checked for free movement on the clutch push rod but it is tight even after adjustment on bar control etc, I have loosened the plates a bit as well to no avail, when the clutch is pulled it does loosen the plates in the basket so not sure whether to cut losses and go for conway clutch? I have 4 clutch plates and strangely in the back of the basket I have 2 pressure plates next to each other, could this be part of the problem?
 
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Howard

Well Known and Active Forum User
VOC Member
If by "pressure plate" you mean the plain steel plates, no there shouldn't be 2 together, and yes that could be the problem. It sounds as though you're "one plate short of a clutch" so to speak. That could also account for the tight push rod.

H
 

Howard

Well Known and Active Forum User
VOC Member
If you upload a photo of your clutch (dismantled) I'm sure someone who knows more about Burman clutches than I do, will put you straight.

H
 

b'knighted

Well Known and Active Forum User
VOC Member
If the pushrod is tight, the clutch has a right to be disengaged. I agree that if you are a plate short it will need a shorter pushrod but first check the adjustment on the external adjuster that alters the position of the lever pivot inside the kickstart cover. Jumping straight to a Honda clutch seems a bit extreme if the Burman clutch components are in reasonable nick as these items can be made to work even with the A Twin's power. Making a shorter pushrod (or shortening the existing one) would be an easier first step. Two plain plates together will not cause a particular problem so long as the plate being pressed against the friction plate is driving the clutch hub.
Reference to WitakerPedia 3.4c may help out although I believe this may be difficult before the system recognises you as a VOC member.
https://www.voc.uk.com/net/docs/3.4c/3.4-301-7.pdf
https://www.voc.uk.com/net/docs/3.4c/3.4-210-22.pdf
https://www.voc.uk.com/net/docs/3.4c/3.4-282-15.pdf
https://www.voc.uk.com/net/docs/3.4c/3.4-302-9.pdf
https://www.voc.uk.com/net/docs/3.4c/3.4-353-31.pdf
If you cannot access these send me a PM with your email address and I'll try to copy the text of these bits and send them to you,

Cheers,
 

Howard

Well Known and Active Forum User
VOC Member
"Two plain plates together will not cause a particular problem so long as the plate being pressed against the friction plate is driving the clutch hub. "

Sorry Ian, you're right, I must have been having a bad day.

H
 
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