Clutch Woes
 

Is it just my clutch master cylinder that requires frequent bleeding, or is it everyone's ?. It's a 2004 999BP, it works fine after bleeding it at the master cylinder, but it has only been about 1000 miles since I last did it. This can't be right can it ?

Does anyone know of a long term fix please

ive just had my slave cylinder replaced as it started leaking. keep a close eye around it for fluid.

That doesn't sound right to me. If it's till under warranty, I'd get it back to the dealer.

Jon

Just a thought but what is prompting you to bleed the clutch, for example are you having difficulty in selecting gears??


Regards

DaveO

I have been through 2 already on my 2003 999s::(

Dave

I took it out at the weekend, when I set off all was normal. After about 60 miles I noticed that when the clutch lever was pulled in there was very little initial resistance and it didn't feel as though anything was happening until about halfway through its total travel. The biting point had also moved closer to the bars though I could still get neutral without too much difficulty. There was no 'creeping' whilst in gear with the clutch disengaged so it obviously wasn't dragging

Upon getting it home and bleeding the master cylinder it was immediately noticeable that there was resistance as soon as the lever was pulled in. The biting point had also moved out to the point where the lever was almost fully released

I reckon that if I had continued riding it then I would have lost the use of the clutch altogether

Its out of warranty but going in for a 2 year service in the next couple of weeks, so they should be able to find out what is going on

I don't think that the plates are worn, I suspect that its sucking air into the system somewhere

Its worrying that people are having replacement slave cylinders fitted already. Do they gradually fail or do they just malfunction without warning ?

I think your correct defo air getting into the system, pretty simple system really. Is the fluid level dropping indicating a loss of fluid?

You can check the banjo connections and look for signs of fluid loss. The only problem I have had was the slave cyclinder seals failed and I had a similar experiance although the fluid leaked from the bottom not helped buy a missing cap headed bolt.

In simple terms the slave cylinder looked to me like a bellows/piston type of system that pushs the operating rod out overcoming the clutch pressure plate springs disengaging the clutch then returning back under spring pressure when the clutch lever is released. In my case I suspected on the return cycle a small amount of air was being sucked into the cyclinder progressivly getting worse until you bleed it and it all starts again.

The slave cyclinder has what looks like a Viton O seal and the operating rod has little black O seals preventing oil leaking around the cyclinder or traveling along the rod into the clutch. If these are still tight it will explain the lack of a visable oil leak.

You could back off the slave cyclinder securing bolts slightly give it a tap and see if you get fluid dripping out.

Just a few thoughts maybe Nelly can help you?

I understand people replace the oringinal slave cyclinder for an after market item which improves feel and lightens the clutch feel slightly. I have seen these in various colours for sale on ebay cheeper than the OEM item.

Regards

DaveO

it sounds like it is not adjusting when the clutch wears, it's not somthing stuped like the span adjuster,
when the leaver is let out it should draw in new flud from the resevoir but if the piston is not returning fully it cant adjust for the clutch wear.
when you bleed it you fix it till the clutch wears.
:burn::burn:

It is not uncommon for the original slave cylinders to let fluid back past the single "O" ring when applying pressure.

Nelly up at Cornerspeed has designed a new type of slave with greater surface area for a lighter action, and three "O" rings to prevent just this from happening.

I happen to know he has some new stock coming in later this week, but not sure how much they are, though I seem to recall they are less than a ton.

Suggest you drop him a line or give him a call.

Thanks for all of the responses. Its going in for a belt change next week and a check over, I'll get them to inspect the seals in the slave cylinder as they sound as if they are the prime suspects. Will update the post with the diagnosis

Me and the wallet agree that its not like running the old R1 :(