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Hello, new here, from the other side as I have a 750 super sport but I'm blessed with the same engine as the sport. I'm always on the ducati forum but there are only 3 of us with dry clutch 750, so I hope I can resolve a few gaps in my knowledge. The clutch is the mystery to me and I need to change the seal on my slave as it weeps a bit. Its the original as far as I can see and has covered nearly 50,000 miles. It was seized sold when I bought the bike as it had stood for 8 years. I had to pump it out with grease. So the question is, is it best to replace the whole piston or new seal and replace the bearing the top hat sits in?? Any help would be great. Thanks Paul

Unless the piston is damaged below the seal line or you can't get the bearing out without damaging the piston there should be no need to replace it. When I did mine several years ago I just bought a new bearing from the local bearing shop and a new seal from the local brake shop. Cheap as and no need for Ducati parts.

do check the P750 FAQs

Thanks for that, I will strip down and get a new seal, I have striped the bearings out and greased so will just change the seal for now.

I believe that I can grease the splines on the clutch plates but what grease is best please??

lumbux wrote:I believe that I can grease the splines on the clutch plates but what grease is best please??

None , nothing . NO grease or oil of any type or description in that clutch housing at all . Its a DRY clutch . Even a tiny bit of oil vapour leaking from an ever so slightly worn seal will cause your clutch major grief

Actually, there are a bunch of guys experimenting with greasing their dry Ducati clutches, and having pretty good results. They are using Lithium Lube and claim it works wonders. Lots of discussion about it on Ducati.ms

Ducati.ms - The Ultimate Ducati Forum > Mechanical Tech Discussion > Hall of Wisdom
> Grabby, shreiky clutch and the simple cheap fix

Cheers,
Phil

I've just lubed the clutch splines on my BMW K75 - a job that's supposed to be done every 20k miles or so. It's a dry clutch and the grease must only be applied sparingly to the actual splines. The lube recommended by BMW is Staburags NBU 30. I had real problems getting hold of this in the UK, but I'm given to understand it's more readily available in Germany and also the US. I've not thought to use it on the Ducati clutch, but a small amount in the right place might help.

edit - Lumbux, I've just noticed you're also based in the UK. If you send me a pm with your address I'll send you some Staburags if you're still keen to try some on your clutch splines.

Thanks for that everyone. I'm going to look at the order my plates are in first as I didn't know there was a special order and not sure if anyone has taken them out before. The reason for asking for the grease is I've decided to fit an open clutch cover with a modified Honda slave cylinder inside. I don't want to cut the clutch cover as I know these are getting hard to get hold of and I want to let the clutch noise out(if it can be hear it over the exhausts). Oh and both types of grease are available on the eBay just looked

with a modified Honda slave cylinder

let us know more about this

Being in the UK an open clutch cover will also mean more rust on all clutch components.
If you don`t want to open it completely you can put one or two washers under the clutch cover to get some of the noise, dust and heat out.

G.

There is a tread in the supersport section on the ducati UK forum, if I can get on the computer (I'm on my phone) then I'll pop some pictures on, it is a work in progress. I don't tend to go out in the wet if I can help it, I'm a fair weather biker!!

I`ve never heard about a fitting Honda clutch piston.
If you want an original this`ll do http://www.mdinaitalia.co.uk/cgi-bin/co ... =19590023B (the same is on ebay UK for 33 & free shipping)

I've had a look at the thread it's about fitting a Honda clutch slave inside a later model clutch cover. It sounds far more work than it's worth. I'm not sure how bad the original clutch components were but as long as the bore of the slave cover is not scored and the inside wall of the oring groove in the piston is still smooth and not pitted etc then the original clutch should work fine. The piston does not have to be in perfect condition along it's outer wall as the only part in contact with the bore that is important is the oring itself. Last time I "rebuilt" mine after I got the bike I purchased a new bearing from the local bearing shop for a couple of dollars, similarly I purchased a new oring from a brake shop again for only a few dollars and the clutch worked fine.

In theory I like the idea lumbux but not sure it's worth the effort unless you have a damaged cover or bore and can't find another one cheap. I see a couple on ebay or somewhere searching last night and they were listed for 200 odd Euros if I recall which seems excessive. Unless your cover has been down the road it would be cheaper and better long term to get the bore stainless steel sleeved and buy a later piston kit or buy an old stock slave from a later bike for the piston if you can get it cheap.

I'm tossing up getting an old friend to machine me a new piston out of stainless as a spare but in reality the piston is the least of the concerns. Even my second covers bore is a bit ugly looking out near the top but it is not really pitted and it's the area above the oring anyway so again is almost unimportant.

I think too from memory it was on the advice from this forum that when I rebuilt mine last time I used one of those tapered orings with the groove on the underside that flare out under pressure to give a better seal to the bore. Pulled it out last night and it looks fine still but will probably replace anyway for the cost.

Just need new friction plates now it seems as mine are about .2mm under minimum spec. Not sure whether to find some cheaper later model friction plates or whole new kit from Stein Diense which is a lot dearer.

The Honda slave is inside a ducati corsa open clutch cover. Had to shorten the slave cylinder itself by 5mm. Mounted a bearing in the piston and made a tophat to fit. So far I would say into about £40 and an hour fiddling. I've just got to mount it in the cover, going to make a cradle out of a piece of stainless steel pipe that will bolt to the cover. It will all be polished at the end with the black slave cylinder and jazed up clutch. There's nothing wrong with the standard clutch cover, I just like fiddling!!

any pictures ?