Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > Clutch Problem

[dukess1999]

Read with interest the recent postings about slipper clutches and meant to sort out the plate order in light of what was said. However yesterday suddenly lost drive completely on my 748; engine fine, gear lever clicks into all the gears but it's like I have nothing but neutral. Bike has slipper and Evo slave. It always made a horrible graunching sound when moving off in first so I replaced the sintered plates with stock which helped for a while but the graunch has come back recently. Bike always changed very sweetly between the gears. There seems to be a little bit of extra play at the lever but still plenty of resistance - the pressure plate moves etc. Any advice appreciated.

[KoolKav]

Sorry I can't help out. Mine make's the crunching noise only when moving to first gear. Rest of the time it's fantastic. Maybe I'm being pendantic? Are these clutches supposed to make these noises normally?
If so I can live with it. If not I NEED THE SOLUTION!!!

[stephens]

A couple of quick questions;
1. Was it slipping at all before you lost drive completely?
2. Does the clutch lever action still work properly? (The slave cylinder may have seized)

[dukess1999]

I seem to be continuing this thread in the 'For Sale' section as well; apologies!

To Stephens: ihere didn't seem to be any slipping; there were new clutch plates in a month ago.
There seems to be little bit of extra play at the lever, but there is still plenty of pressure eg pressure plate moves out etc. I've had the slave off and the piston moves ok.

I've replaced the pressure plate bearin but this doesn't seem to make any difference. The pressure plate etc stays stationery in what would be neutral, and spins when in gear but no bite/drive when clutch is disengaged.

To Koolkav: previous posts seem to indicate that putting a friction plate in first ie up against the back of the clutch basket might remedy the 'crunch'. I'll try it when I've got the rest working.

[Jon]

Dukess. The reason that you have to put a friction plate first is that, with the tangs around the outside this holds the friction plate in place. A steel pressure plate only has the teeth around the inside dia. This is to transfer the drive from the hub to the basket. With a slipper clutch the hub is in two parts, the central splined part is seperate to the friction bearing plate to the far end. The hub can only drive in one direction, when engine braking occurs the central part of the hub moves forward, this removes the pressure the plates had on one and other.Because the friction plate is the first to go in, it can not move because it is held by the basket. If it was a steel plate first, this can slide of the end of the central hub section and slip be hind the hub preventing all the plates from pressing together. Hope this all makes sence. You should have a f'plate first then a plain steel plate, then F/P and then the concave plate, marked with a dot. Test the plate on a flat surface. If it has no or very little curvature get them replaced.

Remember F/P, s/p, concave plate with dot towards you, f/p, s/p and so on until the last but one s/p. This also should be a concave plate, this time with the dot away from you. finish with a s/p and measure the gap from the face of the s/p to the edge of the hub, this should read on a slipper 4 -5 mm.

Jon

[dukess1999]

Thanks for the input Jon. I eventually worked out that the pack was too 'short', ie it wasn't snug against the pressure plate. Installed as you suggested with friction plate first and extra steel plate; the graunching in first is a lot better, though ironically the rest of the gear changes are a bit more agricultural. I assume the 'shortening' was due to plate wear, a bit worrying since I bought and installed them only a month ago. The pack was supposed to be specifically for a Ducati slipper (£50 more than standard!); could incorrect installation cause premature wear?
Checked the 2mm plates and any dishing seems imperceptible, and no dot. Anywhere one can purchase these plates without springing for a whole pack?

[Edited on 16-9-2003 by dukess1999]

[uncledunnie]

I experience the same noise when engaging 1st and taking off. However I do not have a smooth transition into first, it is a mixture of noise and clutch slip. I have a Bucci/DP lightweight slipper witha "road pack" fitted

[Whele]

I suspect if you have looked through the whole pack and there are no dished plates (ie no plates with dots) then this is what the problem is. Go to JHP and buy two dished plates. Install them in position 1 and 12 facing inwards.

Some people who like a good clutch action run with 4 dished plates.