Clutch sticking
 

I got my dads curvy up and running, but the clutch seems to be sticking. The symptoms are as follows:

1) With engine running, clutch pulled in any attempt to get into first launches the bike forward and stalls the engine.
2) With the rear on a paddock stand, with the engine running and in gear with the clutch pulled in, it's impossible to stop the rear wheel turning by hand (I have a friction burn on my hand to prove it!).
3) If I use the rear brake, and open the throttle to stop the engine stalling the clutch will free up and the rear wheel will stop turning, even after I release the brake. The engine will then idle happily in gear with the clutch pulled in.
4) If I let the clutch out, it takes up progressively as normal, but once fully engaged it sticks again.

I'm 110% certain this is not an adjustment issue, the clutch push rod has plenty of motion and the clutch only takes up near the end of the lever travel. Once freed the clutch does not drag at all. I've tried slipping the clutch a bit (i.e. in gear with rear brake on) but it hasn't really helped.

Everything points to the friction plates sticking to the steel plates, but why? It was fine before the bike was stripped down last year, and the only things I've done to the engine are new valve shims and new oil (semi-synth 10W40) and filter. The bike has obviously not been used for quite a while (~9 months), is a decent bit of use likely to help?

Re: Clutch sticking
 

You state that the only things you've done are valve shims, oil + filter...but when were they done?

Have you tried taking the plates out and looking at them? And have you checked the basket to see if that's worn?

Re: Clutch sticking
 

Plates that don't get run too often can get sticky and a change of oil and a good run can sort out a sticky clutch.

You never know, it could be as simple as that. ;-)

Re: Clutch sticking
 

nice and easy to drop the pack out of curvy and see what's occurring in there

Re: Clutch sticking
 

Shims were done about a month ago, oil and filter were done a couple of days ago. Engine is running very nicely in all other respects.

Not taken the clutch out yet, I'll take it for a quick ride tomorrow and see if the problem remains before I strip the clutch down. It just seems odd how it was working fine before the layup - wondering if the previous owner (who was a ham fisted gorilla by anybodies standards) used some incompatible oil that has affected the friction plates.

How far do you need to lean the bike over to avoid having to drain the oil when you remove the clutch housing?

Re: Clutch sticking
 

Sidestand is fine

Re: Clutch sticking
 

Just to close this, after a ~15 mile blast the clutch freed up of it's own accord, and the bike passed it's MOT today with no advisories. Thanks for all the suggestions, at least I know I can replace the clutch without having to drain the oil when the time comes!

Re: Clutch sticking
 

Im having the exact same problem but comes and goes... sick of it now..changed the oil but still same