MAJOR clutch problem

[Jashdown]

Ok, so a couple of days ago, my clutch decided to just basically fail. I'll mention now, that the clutch had been working perfectly for the entire time I owned it.

I was leaving a petrol station and when I pulled the clutch in, it felt softish, the lever didn't feel as springy as it was before, but still springy. It also had no feel at all, I couldn't find a definite friction point anywhere, and if I tried to take off as I normally would, I would get about 5-10 seconds of clutch slip before it finally grabbed properly, alternatively, I could just drop the clutch completely, even at low revs (4-5k) the bike wouldn't stall if I dropped the clutch, it was would just grab after about a second of slipping.

The clutch disengages perfectly fine, and it will engage, but it just takes ages to do it. I've adjusted the clutch cable both at the lever and the engine and it hasn't fixed the problem.

My dad thinks it's the diaphragm springs that have shit themselves. I pulled the clutch cover off and removed the circlip and the little outside cover of the clutch basket, the castle nut is tight and the outside diaphragm spring looked to be in good condition.

On the sprocket side of the engine, I took the front sprocket cover off, and the rod that is part of the clutch assembly was showing, I could push and pull the rod completely through both ways, so I can't determine what the specific problem is.

Any help would be greatly appreciated. Thanks.

[iDemonix]

Seems odd for it to happen so sudden, is the lever mechanism definitely all a-ok? Where the clutch cable goes to the left side of the engine, to the sprocket cover, when you let the lever out/in it obviously operates the pushrod that you played with, there's a little spring between the clutch cable and the pushrod, is that clipped on properly? The reason I say this is because after I replaced my clutch, that spring wasn't on its little notch properly and although there was a bit of spring, it wasn't normal. Clicked the spring behind it's little holder thing and it had a proper squeeze to it again.

Bit of a beginner here so don't take my advice as golden though

[magg]

If we are talking NC30 there is a sprag clutch within the clutch that lets half the clutch slip when engine breaking exceeds rear wheel grip. Maybe the sprag clutch has failed, unusual perhaps but possible.

[Jashdown]

Yeah the lever mechanism is all fine. The spring on the sprocket cover is in its place and working fine.

Magg, it's the 35, so not sure if it has the same system as the 30, but I doubt it.

When the bike is switched off, I can put it into 6th gear and push the bike with the clutch engaged, can't push it when it's in 1st though. So the clutch has pressure on the plates, just not much pressure.

Diaphragm springs? Can someone explain how they work and how they are set up?

[iDemonix]

Not sure for the '35 but on the '30 you should have three of them on top of each other, watch the video in the workshop forum about changing a clutch.

[Jashdown]

Are they concave/convex though? I have no idea how the diaphragm spring system works.

Are they just stacked one on top of the other, so like concave/concave/concave, or do they altenate convex/concave/convex?

[iDemonix]

they're all the same, they're shaped like a dinner plate.

[Le_Blur]

It may sounds daft, but have you tried just oiling your cable? My clutch displayed exactly the same symptoms as yours right before it snapped. It was only then I realised I should probably have oiled it a bit more frequently. Just a thought, like...

[Jashdown]

I thought the cable at first, but I don't think so.

A mate of mine had a fucked cable and his clutch behaved in a similar manner to mine, but not quite the same. It would engage completely, but it just wouldn't give much feedback do you didn't know if it was engaging properly or not.

Is that clutch rod (the one that pokes right though from the clutch to the front sprocket) meant to be able to move completely freely? I could pull it out without trying.

Also, the basket cover thing behind the circlip, is that meant to be able to move backwards and forwards inside it's area so easily?

[magg]

Rod should move freely, the diaphragm springs (3) are under the castle nut. The basket cover behind the circlip is the pressure plate lifter and may move until the push rod is extended and contacts the bearing in the centre of the pressure plate lifter.

Hope that helps.