QuestionKawasaki zx10 1988
When engine braking there is a heavy grinding noise from clutch
housing right side of the engine, this happens when releasing the throttle.
During acceleration no problem, gearshift up and down no problem.
only during deacceleration.
The noise disappear in that moment that the clutch lever Is pulled, like shifting gear.
any good ideas
128000KM
kind regards
Kent
Answer
ZX10 Alternator Drive 
Tensioner Installation
Hello Kent,
That could be a tricky subject to sort out, mostly due to increased mileage of your engine.
First of all, it might not be a clutch issue. The thing that the noise disappears when you pull
the lever, may be because the engine RPM fall.
Is this noise present at idle? If yes, does it stop when you actuate the clutch, or when you slightly open the throttle?
There are several things in your engine that could produce that kind of sounds, but most of the times I've encountered a loud one, it was the alternator-chain-tensioner, that is located next to the clutch basket (see picture).
Resuming, I'm not saying that your clutch has no problem, but when it does, the sound is more like a knocking than "grinding". Check the alternator chain, chain guide and tensioner first.
(Part Numbers: 92057-1209, 12053-1189, 39170-1055 respectively).
However, if you remove the clutch cover and you find the tensioner intact, check the clutch basket for extreme slack by moving it to all directions and get back to me to let me know your findings.
Best Regards,
Lazaros.
Revision/Addition:
The tensioner fails in two ways. First and most common, the rod-stop-lever breaks at the point
I've marked in red in the picture. CAUTION!!! If that's the case, you have to "fish out" the missing steel piece with a magnet.
Second, the lever spring, I've pointed in green in the picture, may also be broken and MUST ALSO be found and removed from the crankcase.
Good Luck.
Regards,
Lazaros.
