Clutch not disengaging properly

[Greybeard]

During my run out yesterday the (original 6 spring) clutch became tricky to disengage, requiring gear changes to be anticipated so that the clutch had time to release. Seems to be related to fully warming up. I'm running the clutch in the (tiny) recommended volume of ATF fluid. Any ideas?

[bsa-bill]

following a rebuild I'd look at the cable run before pulling any covers off, could easily have found some slack somewhere and settled out of adjustment

[Greybeard]

Good thought BSA-Bill. If the clutch is still sticky when cold I'll be suspecting the cable action.

[A10 JWO]

Hi Neil
I had a similar problem and spoke to an old expert Dave Hopwood from Barkingside. He explained that the six spring clutch did not suit the A10 range, but worked better on the Unit Construction 650's. I have a new 4 spring setup, old basket which I cleaned up and new Plates from those nice people at Kidderminster Motorcycles. I feel that I might get some negative comments in the next few days for this, BUT it worked for me.
Regards Colin

[a10 gf]

the six spring clutch did not suit the A10 range

'Six spring' always been excellent here, with good parts & exact adjustment it should perform well with no problems.

clutch became tricky to disengage

heat (slipping?) >>> expansion (disengage problems)

[Greybeard]

I'm not keen to change to another clutch type.
When I reassembled the clutch I just put the old, (probably original) plates back and set each of the spring screws to be level with the top of the spring buckets. If the clutch was slipping I'd suspect the springs or friction pads.
I'm away from home at the moment but when I get a chance I'll be investigating the clutch and the carb.

[A10 JWO]

Hi Neil.
Not trying to get you to buy a new clutch, just trying to be helpful. Mine used to go in gear but would not come out of first. I cleaned my basket up with a fine file and popped in the new plates. Felt like I had a new gearbox.

regards Colin.

[Greybeard]

Guys, I'm happy to hear any suggestions.
Cleaning up the basket slots sounds like a good idea. If I have to strip the clutch I'll do that.

[muskrat]

G'day Niel. Also make sure the pressure plate is lifting squarely. Individual spring adjustment will be needed to rectify.
Cheers

[gold33]

As per others I would check the cable first (it's the easiest) then the pressure plate alignment.
Just a thought from my personal experience with similar symptoms, check your clutch nut tension and ensure the tab washer is fitted correctly; before coming so loose as to be almost non functioning my clutch would get worse the more I rode and then miraculously improve for no apparent reason, I discovered the cause when the whole clutch assembly fell off and I came to a halt!

[KiwiGF]

After eliminating the "easy" fixes as the cause when you strip there are quite a few things to check during a strip down. My 6 spring works perfectly by the way, but its almost all new. I use a dial guage to adjust the springs and get the pressure plate lifting squarely, its not hard to rig that up. It took me a few goes to get the tension right so it did not slip and it's on the heavy side to operate but I can find neutral easier than my modern bikes. I get the pressure plate movement to within 010 measured in 4 places but it probably does not stay like that for long....

One thing to look out for is quality of plates i got new surflex brand plates from draganfly, both for friction and plain, some aftermarket plain plates are thinner than std and are not flat and cut the baskets up quickly.

I use red sae30 grade lawnmower oil in the chain case and the only effect of over filling is that it leaks from the diamond plate behind the clutch, it does not cause my clutch to slip or drag when over filled and at least i know the chain is getting plenty of oil! Red so i know whats leaking....it does not leak much anyway.

[duTch]

 Hiya Guys, this is right up my alley at the moment, ok all's ok, but have had similar issues.

 All the ideas are good, but we need to remember that I think Neil you have a Plunger 6 spring (?),and while basically similar, also not same......?
 
   Mine was fine to start, but was slipping a bit, no great surprise, I figured it would. I added the fifth friction plate working on the theory that more friction material would allow for ~less spring pressure (?).
  Ok, but after a lap or two, funny noises, dragging and slipping but as I had to pull the cover off anyway to tend to something else, no probs, but found that the spring nuts had unwound-hence funny noises....
  I'd bought some new springs from DragAnfly, so went to put them in but realised they are right-hand wound, rather than left hand -what's the latest consensus on this? I don't agree, and contacted them, but was told it doesn't matter,but explained back that the tabs/indents/unwind/stuff-haven't heard back, so used other springs .
   To cut it short, Neil, I put a 2"hose clamp over the hand-grip and lever-end, just tight enough to hold the clutch disengaged, bike on centre stand/blocks, whatever to get the rear wheel off the ground, top gear and spin the wheel, you can see the run-out ,if any, by eye, or threaded rod in one of the cover stud holes and improvise a 'run-out' gauge, and as previously suggested adjust each spring till it runs true. Also worth marking one of the springs/nuts so you have a reference point.
  The last couple of days mines fine, time will tell.
 Also I've been slipping it out of gear at lights, and find to get into gear again (at standstill) is best to hold the clutch in a few seconds before selecting(I think it takes those few seconds for the plates to separate,and run freely).
 (also I use a  paper gasket, with three bond both sides, but on the engine side surface put silicon grease, which allows for easy release/reuse, and have had the cover off a few times and it still doesn't leak-yet, but means it's only a beer or two to do the job).

Good luck, hope that's helpful, duTch
 





 

[Greybeard]

Thanks Dutch,
My clutch is working properly when the engine is cold so the dragging is related to warming up. If during another decent ride the clutch plays up I'll have to decide if I'm going to take the cover off. I really just reassembled the clutch and I'm pretty sure it's all original so I'm not surprised it needs some fettling.

[Greybeard]

A bit more information about my sticky clutch. I've just returned from a ride and got the bike really warmed up. With the engine stopped I drew in the clutch lever and tried to push the kick-starter down. At first the clutch wouldn't release but then suddenly the clutch released. Does that help diagnose the problem?

[muskrat]

The clutch should release within 1/4 of kick starter stroke.
Is the domed cover fitted and the correct amount of oil in there?
May need to back the springs off a tad.
My plunger clutch is sooo sweet. The only time it gives trouble is when the engine wet sumps and oil finds it's way into the primary.
Cheers