[nomadwarmachine]

Two questions not necessarily related concerning an '96 M900 engine:

-This is more of a general knowledge tech question, but when is a dry clutch nearing the end of its life? I have 23K on this clutch and it still works fine (still sounds like a machine gun in neutral, but nice and quiet when engaged). I have no trouble shifting, just curious whether the clutch noise modulates relative to wear.

-Modded the bike with hi-comp pistons, stage II jet kit, aluminium hi-mounts, and a K&N. Any recommendations on what my new plug gap should be? I've got it at the recommended gap for the engine, but don't know if it should go wider, and by how much.

Thanks!

 

[simcor]

I have a '95 m900 with vented clutch cover.
Most of the noise from the clutch probably originates from the plates rattling around in the clutch basket "fingers".

 

[simcor]

Just checked the book of words (Haynes), and:-

...plate tang to basket clearance : 0,6 mm max.

...friction plate thickness (900 model) : 2,8 mm min.

Hope this helps.

...Simon

 

[nomadwarmachine]

Hmmmm...judging from a spot check of the clutch plates, I am well in excess of the .6mm that you mentioned, more like 1mm, plus it is shifting a little bit harder than before. Maybe time for a refresh...

When I replace the clutch, should I replace friction plates and steel plates, and springs, or just the friction plates? Was going to go with a Barnett carbon fiber, since these seem to last the longest, and I am not too hard on the clutch...

 

[simcor]

I replaced my plates at around 18K kms (and this set is still going at 38k kms...). I got a set of replacement plates from the local Ducati dealers. They come with both friction plates and steel plates as a set - not seperately available.
I know of companies that do re-coat the friction plates for you, so if the stellies are OK, then this is an option - but I don't know for how much !
I believe the Barnett clutch plate kit comes as a set as well.
It may be possible for you to file the basket fingers, to see if this'll smooth the edges up and reduce the chance of the plates being caught when moving axially along the fingers when the clutch is depressed. This may ease the pressure of clutch changes, if it's increasing.
It may be possible to get another steelie and fit this in if the friction plates are wearing right down (fill in the gap - so to speak), or to increase the spring tension - to hold them together more and maintain friction pressure.
I didn't replace my springs, because they were all around the same free length, and within Haynes specs.
If the clutch basket is fairly worn, then it may be worth considering a Barnett clutch basket as well. More $$$ but you'd end up with a "new" clutch internals matching the plates, and reduce a little bit of weight in the process (both from the bike and your wallet ;D ;D ;D)
Even the Ducati stock baskets are pricey
Good luck...
...Simon

 

[dougk]

I replaced my clutch basket and plates with Ducati original and measured .6mm clearance from new. I don't think I'd concern myself with replacing at .6mm. YMMV I now use a Nichols basket and Barnett plates. Quiet,better wear and spins up nicely.
Spark gap is dependent on available energy from the coil. Stock coil, stock gap ,although most people use plugs straight
from the package with about .034" gap instead of the called for .024"