Funny clutch!

[otruk]

Having trouble with my clutch, maybe its the weather!

Have replaced intermediate bearings on g box and as the bikes used every day put in new clutch and slave cylinder. Noticed after a month of riding that the clutch actuation is getting closer to the bars, until just a few mm from the clutch being fully pulled back. Have re bled the clutch and no air, but....... the fluid is dark grey. Is this contamination from a decaying master cylinder seal or elsewhere? Advice other than sell it would be appreciated.

 

[beemer pimp]

Sound like clutch slave cylinder seal gone .

Val

2 bikes , twice is happy

 

[DrFarkoff]

If you pump the clutch lever does it pump up okay?

It could well be a stuck Slave cylinder bearing

I had this on a customers bike may moons ago and narrowed it down to that

the shaft through the box turns all the time There is a small bearing in the middle of the slave cylinder that should allow the two movements to be separate

The bearing sticks whether through dirt, debris, rust, etc etc and the whole centre portion of the slave cylinder piston revolves in the slave cylinder causing friction and I would think erosion of the seal. Hence the dark fluid (which could also just be from overheating!)

 

[otruk]

The clutch seams to pump as it should, its just that the biting point is so close to the grip. I was going to put in a master repair kit and thought the contamination was coming from the degrading seals.

Though after what you said maybe a closer inspection of the slave cylinder is needed. If the seal on the push rod (which is new) leaked, the oil would bypass the slave cylinder and get onto the engine?

 

[DrFarkoff]

The one that I did was Moist but not prolifically leaking

If you are fiddling about down there dont forget to tie the centre stand to the front wheel as it takes very little bumping and pushing to move them off their stands

begging your pardon if I am teaching to suck eggs but have had to tidy up after a couple of folks didn't do this! and got hurt quite badly !

 

[otruk]

I suck at most things!

Just fiddling with my fittings now.

 

[Steptoe]

If the seal on the push rod (which is new) leaked, the oil would bypass the slave cylinder and get onto the engine?

What oil ? The only oil that could migrate along the clutch pushrod would be gearbox oil, and that would mean the gearbox input shaft, output end seal, was leaking and that would have no effect on the biting point of your clutch or the colour of the clutch fluid..

 

[otruk]

The fluid is a dark grey colour, I don't believe its oil,as you suggest a leaking slave cylinder and push rod seal would be too much of a coincidence. Think the problem may be with the master cylinder, after 175k i suppose it reasonable that the seals degrade and will effect the fluid colour. This may account for the lousy biting point, though I would have thought I would see air when bleeding the circuit?

 

[moonhead911]

the bearings gone in your slave spinning the hole thing ripping up the seal then turning your fluid gray i would buy a new one and pack the bearing well with grease

 

[moonhead911]

 

[otruk]

When I took the gearbox out the slave cylinder, though only a month old looked like this! May explain the occasional faint rattle!

 

[Steptoe]

the bearings gone in your slave spinning the hole thing ripping up the seal then turning your fluid gray i would buy a new one and pack the bearing well with grease

His slave cylinder was new.

 

[moonhead911]

His slave cylinder was new.

still no guarantee its not faulty. i bought a new one from motorworks it started leaking after 6 months they inspected it and replaced it faulty batch

 

[otruk]

I guess I know what i am doing tomorrow! Will update at some point.

 

[otruk]

The master cylinder looks to be in the same state as the photos also with a loose bearing. Well that one lasted 8 months then! Thanks for all the help/advice, Merry Christmas etc.

 

[moonhead911]

The master cylinder looks to be in the same state as the photos also with a loose bearing. Well that one lasted 8 months then! Thanks for all the help/advice, Merry Christmas etc.

were did you buy it from it should come with a years warranty if it was brand new. i would recommend packing your new one well with good grease most of them hardly have any on the bearing
thanks