Hello,

Has anyone got any information regarding the SBD slave cylinder and to weather it is self adjusting?

I have an issue with mine where I have just had to change the clutch due to it being worn out.

Now when I have reinstalled the basket/pressure plate on to the front of the clutch I seem to have some back pressure on the slave cylinder as the centre actuating rod that goes to the pressure plate is sticking out by about 5-6mm I can push the centre pin back in and the slave cylinder retracts, but the master cylinder is on its most forward position so after i let go it comes back to this forward position. This is putting pressure on the pressure plate of the clutch when it is not being used. The bite point of the pedal is within the first 1inch of travel so it doesn't need to be depressed very far.

Does anyone know if I just need to bleed the slave cylinder or space the slave cylinder from the block?

Thanks

John

[Edited on 5/6/13 by jwhatley]

Most bike slave cylinders have a weak spring inside which pushes the piston outwards.
It is not strong enough to cause clutch slip - just takes up any slack to the pushrod.

When you installed the clutch and you pushed the rod in this should displace the fluid back into the master cylinder.

There should be no residual pressure in the clutch hydraulics.

If you crack open the slave's bleed nipple and the fluid spurts out under pressure then you have a problem with your master cylinder.

Either the master cylinder push rod is too long and the piston is not returning past the inlet port or the seals are stuck.

This would cause premature clutch wear (or give the symptoms of a worn clutch).

Once you sort out the master cylinder - fit a pedal stop to prevent over-extending the clutch which can pop the plates and cover out of the basket grooves.

[Edited on 5/6/13 by minitici]

Does your clutch pedal have a return spring and is there play in the push-rod when the pedal is released? Either of these would cause the slave to not return fully.

What size master cylinder do you have? From what you say about the amount of movement to release the clutch you could do with a smaller diameter master to give better feel. A fairly long, light clutch makes the car a lot nicer to drive than a "binary" one.

I think I've worked out what's wrong.

Removed the slave cylinder and if you push it in it returns back to its original position no problems with it there.

The clutch pedal returns back to the fully extended stop within the master cylinder when the clutch pedal is released, so I don't think there's any problems there either.

BUT....

The push rod that goes through the engine to the clutch basket is a bit too long as its pushes the slave cylinder back fully in to the cylinder housing so there's no travel left.

So I can either space the slave cylinder out a few mm or cut the centre push rod down a little bit and that should release the mechanical pressure I currently have.

John

Think I've seen something before on here about that problem. I seem to remember both solutions had been used by different people. Do a bit of searching.

Personally I'd try spacing it out as that's a reversible alteration if you're wrong.