C: Clutch Series ‘C’ Rapide Clutch Slip

[danno]

Hi
I hope to take the Vin to a local show this weekend but last time I was out a couple of months ago, the clutch seemed to be slipping.
I looked through the adjustment notes in the rider’s handbook but any pointers or help would be appreciated.
I’ve checked the handle bar/clutch lever abutment sync as described and it seems to be ok. The cable has an adjuster near the handlebars.
The bike’s done around 9k since full rebuild.
Thanks.

 

[Peter Holmes]

Normally the ingress of oil is the cause, not helped if the oil level in the primary chain case is too high, which can occur if the engine has wet sumped excessively.

 

[timetraveller]

Remove the shallow inspection cap on the kick start cover and check that there is some slack at the top of the clutch actuating arm. If there is slack in the cable then you need to adjust either the adjuster in the middle of the pilot clutch or the one in the lower part of the kick start cover. If all these are OK then it is almost certianly oil in the clutch. The pilot clutch should hold up to about 50 mph so if the slip only occurs above that speed then oil in the clutch drum is likely to be the cause. Oil gets down the splinse of the shoe carrier and Vincents used sealing compound on the splines to prevent that, My own solution is to machine a hollow at the inner end of the clutch shoe carrier splines and fit an 'o' ring.

 

[danno]

Normally the ingress of oil is the cause, not helped if the oil level in the primary chain case is too high, which can occur the engine has wet sumped excessively.

Yes. Maybe should check and drain the sump.

 

[Peter Holmes]

If not too severe the overfilled engine sump will sort itself out with the scavenge pump, but if the overfill has ingressed into the primary chain case, then you will need to drain the primary chain case back to the correct level, there is a level bolt/plug in the outer chain case to achieve this, a small amount of contamination might sort itself out with use, oil soaked clutch plates and shoes will require a deep clean.
Good Luck Peter

 

[danno]

but if the overfill has ingressed into the primary chain case, then you will need to drain the primary chain case back to the correct level
Good Luck Peter

The level was just under so have topped up.
I’ve adjusted the cable so there’s a little slack. I’ll see how it goes.

 

[danno]

Started off ok for about eight or so miles then gradually the clutch slip started.
Mainly from 2nd upwards.
I’m sure it’s this rather than mixture but there were a couple of backfires near home.
Just wondering if it’s worth having a look at the linings.
Had to top up the gearbox a fair bit too before going out.

 

[Chris Launders]

Yes you need to have a look at the linings. any oil on them will induce clutch slip at anything above very moderate revs

 

[Alyson]

Normally the ingress of oil is the cause, not helped if the oil level in the primary chain case is too high, which can occur if the engine has wet sumped excessively.

mind you the engine oil should not enter the clutch sanctuary unless it leaks past C18/1 or other entry point. Engine oil entering the primary can be monitored by checking FT188, 188 (level plug on primary cover)

 

[Alyson]

sorry, brain fart, past the seal around the clutch basket, not C18/1