Clutch Slave Rebuild

[Patmac6075]

Ok, so last summer I started having issues with my clutch cutting out….well I think I found the problem.

 

<!--url{0}-->[/img]</p><p> </p><p> <img src=[/img]

 

I’m rebuilding both my clutch and brake hydraulic systems while I wait for warmer weather, figured I’d snap some pic’s, maybe some of our more knowledgeable members can add some insight on this type of maintenance.

I didn’t take any pic’s of removing the slave (there is plenty of info on this if you do a search), suffice it to say, just wiggle it around and just about the time you’re ready give up…stick with it another 45 minutes and it’ll finally kind of back-flip out…helps if you take the bleed nipple off.

 

 

 

This is everything laid out once I got it disassembled ( I just noticed the spring is backwards but I'm too lazy to retake pic's )

 

<!--url{2}-->[/img]</p><p> FYI, I used the grease gun method to separate the piston from the body…hence all the grease on the parts….For those unfamiliar with this method, just use a proper sized bolt to block the banjo opening, open the bleed nipple fully and put a grease gun over the nipple (it’s almost the same size as a standard zirk fitting) start pumping full of grease and slowly let the hydraulic pressure lift the piston out. Just make sure you clean every bit of residual grease out of every nook and cranny, and every passage way!!</p><p> </p><p> There was a lot of caked on crud that I had to clean off, especially where the dust seal attaches…if you’ve gone to all this hassle, don’t short cut here…I used a lot of brake cleaner and a tooth brush (used a small pick on the really tough stuff) to clean off everything I could…</p><p> I also used some 2000 grit wet/dry and some brake fluid to clean up the bore, the important thing here is to go in the same direction as the piston…ie, from top to bottom, NOT AROUND the bore to clean up any caked on crud or any score marks…</p><p> </p><p> <img src=[/img]

<a href=http://i821.photobucket.com/albums/zz131/Patmac6075/ZZ%20Parts12.png' alt='ZZ%20Parts12.png'>

 

That’s it…just reassemble with new seals and liberal amounts of clean brake fluid…reattach everything to your bike and bleed out the system…easy-peasy!

At this point, I’d like to get up on my high horse (somebody please catch me when I inevitably fall)…there is absolutely no reason to go through all this effort and not rebuild your master cylinder at the same time (that write up to follow in a week or so) and replace those worn out rubber hoses with some stainless steel hoses….end of rant!

[Ozlander]

Looks good.

Can I send you mine so you can rebuild it???

[BlueSky]

Thanks for the write-up. But I do disagree on the way to clean up the bore. Seems to me that going in the direction of the piston movement would be more likely to cause a leak. I certainly would have cleaned it up going around the bore. I could be wrong but that is how I always cleaned up brake wheel cylinders. The wheel cylinder hones that are available for purchase for sure hone around the cylinder.

[Marcarl]

Nice clean look, and your right, might as well do it all while you're there anyways. Let us know how it goes with the bleeding process.

As far as honing out the bore,,,, well I would use a hone for that and make sure it goes around and round not uppy and down. Up and down marks will give more to leakage that circular. Also if you do this by hand you have a possibility of getting the bore out of round, not a biggie with the clutch but with brakes that might become fatal,,,, just a warning,,,, 'course on 2nd thought, a clutch that all of a sudden decides it's not going to work can be nasty as well.

[Patmac6075]

Just the way I'd been taught....I suggest each to do as they see fit. Would take quite a bit of scrubbing to get these bores out of round if using 2000 grit. It really should be considered a polishing.

[paysaw]

I just rebuilt my clutch slave on a project bike I am working on. I have no leaks but my clutch will still not disengage. I bled it out fine and there is lots of back pressure on the clutch handle.The master seems fine. Any suggestions how I can look into to fix this? Could I have a problem with the clutch pack?

[MiCarl]

Paysaw,

 

Two possibilities come to mind. The first is blocked line, which shouldn't be an issue if they really bled ok.

 

The second is stuck clutch plates. Was your bike sitting for a long time? The plates can dry out and stick together if they sit long enough. They can also get a bit of surface rust which will lock them up.

[Marcarl]

Two things come to mind Paysaw, one is that you still have an air bubble at the master,,,, hard one to get, and the other is that you might be missing the ball bearing that sits in the cross-over from the slave to the clutch pack. If anyone has had that section apart then the ball bearing is an easy one to loose. I also agree on the stuck plates issue.

[Patmac6075]

Paysaw, did you check inside your master cylinder? There is a very tiny hole (right next to the tiny hole) in the brake fluid well leading into the bore...if that very tiny hole gets clogged it sometimes presents itself as you are describing. Short of doing a complete master cylinder rebuild, you can get some guitar wire and try to clear the orifice.

[bongobobny]

IMHO just replace a slave cylinder with a new one! They are not that expensive! With the cost of the rebuild kit and the cylinder hone if you don't have one plus your time and labor it's cheaper in the long run. Sometimes the rebuilds don't last long depending on how much damage there is to the cylinder walls...

[Condor]