cockercas Posted October 20, 2014 Posted October 20, 2014 Ducati 749s, bikes had a few issues borght with no history. Its got a dry hydralic clutch. The problem.When the bikes warm the clutch is engaging with the leaver in. Eg come to a stop with the bike in 1st, clutch in and after 10/15seconds the bike will creep forward.The master cylinder was leaking so its had a refurbed one on. Clutch plates was nearly flat smooth so its had new plates.Baskets ok. Slaves not leaking.No fluid loss anywere. Obviously new fluid and bled correctly. Any ideas. Quote
Stu Posted October 20, 2014 Posted October 20, 2014 what plates did you replace? friction or steel or both? Quote
Tango Posted October 20, 2014 Posted October 20, 2014 Did you replace the plain plates as well as the friction plates? The plain plates can dish so the clutch doesn't fully disengage.....and it gets worse as the clutch gets hot..... Quote
cockercas Posted October 20, 2014 Author Posted October 20, 2014 Both, friction plates and ali plates. Quote
Stu Posted October 20, 2014 Posted October 20, 2014 for the bike to creep the plates are overheating and warping for them to overheat and warp there has to be a clearance issue Quote
cockercas Posted October 20, 2014 Author Posted October 20, 2014 14 plates out and 14 plates in. Quote
Stu Posted October 20, 2014 Posted October 20, 2014 that doesnt mean you dont have a clearance issue there could still be air in the clutch line they can be a right twat to bleed up over time the air could be compressing more the longer it is pulled for causing pressure loss at the slave cylinder Quote
cockercas Posted October 20, 2014 Author Posted October 20, 2014 Ive bleed it twice. First time was the m/c change. Bled new fluid right through. Then again a week later to make sure there was no air. Any tips for getting the harder stuff out? Quote
Pete Posted October 21, 2014 Posted October 21, 2014 Are you using the original clutch cover? I remember someone telling me once they'd swapped the clutch cover for an open one and had the issue you're describing. I can't remember how it was solved but I think it was either one too many clutch plates, or something else was a bit too thick. Sorry can't be of any more use! Quote
cockercas Posted October 21, 2014 Author Posted October 21, 2014 It has a open clutch cover. The friction plates before was well worn. New plates are 2.5mm and change on them is 2.3mm. The old friction plates was completly smooth. Quote
Stu Posted October 21, 2014 Posted October 21, 2014 Ive bleed it twice. First time was the m/c change. Bled new fluid right through. Then again a week later to make sure there was no air. Any tips for getting the harder stuff out? sorry early start today and was in bed by the time you posted again a good way is to remove the slave cylinder and push the piston all the way in watch the fluid though as it will rise hold the piston and pump it as far out as you dare without letting it pop out again watching the fluid to make sure it doesnt run too low then keep very slight pressure on the piston so it doesnt pop out tap the lines and master cylinder with a screwdriver or something the force the piston back in repeat the process a few times this is a good way to purge and little bit of stuck air from the master if this doesn't make a blind bit of difference then I would be looking at the clutch pack you need to find out what the stock thickness is of ALL the plates and measure them all to make sure they are within spec are they stock items are pattern parts? Quote
Stu Posted October 21, 2014 Posted October 21, 2014 they should all be ok then but doesnt hurt to check Quote
cockercas Posted October 21, 2014 Author Posted October 21, 2014 Il get my calipers out. There was 2ali plates then friction then ali and so on. If all else fails will it be a issue to loose one of the two ali plates so it reduces the stack? Quote
Stu Posted October 21, 2014 Posted October 21, 2014 two ali plates I have never known that! but then I have never had a clutch apart on a duc if he ordered the parts from ducati and the same went in and in the same order as what came out then I wouldn't just lose one! you will probably end up with clutch slip what year bike is it? Quote
cockercas Posted October 21, 2014 Author Posted October 21, 2014 2005.I took them out the bike.From the crank2 ali platesFrictionAliFrictionAnd so on.The ducati guy we got the mc off said to check the new ali plates for curved ones and put them in first. I laid all the ali plates on a mirror and none was curved.Stack hight is 36.5 so il check that with my calipers. Quote
cockercas Posted October 21, 2014 Author Posted October 21, 2014 Thinking about clutch slip. With the old smooth plates there was only a tiny bit of slip. Full throttle and at 5k it would slip. Not much though. Quote
Stu Posted October 21, 2014 Posted October 21, 2014 clutch is in wrong friction first then ali friction and so on ending up with ali plate your supposed to measure the stack height and if you need it thicker you add extra ali plates on the end there should be some curved ones in there! other models with less plates (10) use 2 ali plates first Quote
Stu Posted October 21, 2014 Posted October 21, 2014 http://issuu.com/desmoworks/docs/2005-sbk749r Quote
cockercas Posted October 21, 2014 Author Posted October 21, 2014 The R model has a slipper clutch as slandered stu. I know slippers need to start with a friction plate or the first time the slip if there fitted with steel plate the steel drops and jams up. This duc is a 749s and it's just a normal dry clutch. I can't get the bike untill Friday, but il wip the clutch out and check the stack hight first. Quote
Stu Posted October 21, 2014 Posted October 21, 2014 if its a none slipper clutch then it should only have 10 plates and not 14 the slipper is showing as having 16 and yes the standard clutch starts with two ali plates! something is certainly not right in there! I thought it had a slipper with you saying 14 plates Quote
cockercas Posted October 21, 2014 Author Posted October 21, 2014 I counted 14 out, so figured 14 went back in. Think that's the problem then. Il update on Friday if I can get the bike. Thanks stu. Probably owe you a beer. Quote
Stu Posted October 21, 2014 Posted October 21, 2014 I cant see anything anywhere that states 14 plates its either 10 or 16 you can only try it and see and come back to us in the mean time I will keep looking about for more info Devans needs to read this he will know more than me seen as though he had a Duc plus he knows plenty with them so could ask the relevant questions Quote
cockercas Posted October 21, 2014 Author Posted October 21, 2014 Ok thanks, bikes a 2005 749S with a grey frame. They updated in 2005 and the newer models have a red frame. Just incase that makes any difference. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.