clutch slave cylinder replacement

[MAXdB]

 

I've been searching but cant seem to find a how-to for this. Is this because it's so easy? Do I just empty the current fluid, replace the stock clutch slave cylinder with the aftermarket slave and then refill the system with brake fluid being careful to remove all the air bubble? Thanks in advance everbody 

[ozmanyyy]

It is pretty basic ( I've even done it  ) and pretty much as you said: replace, bleed etc.

Evoluzione has instructions on their website that you can download:
http://evoluzione.net/evo-cycle.htm

[Slide Panda]

Don't empty the current fluid.  Just swap in the new one.  You will have to bleed, and then probably bleed it again (and again) to get all the air out.  One other trick is to leave the lever strapped to the bar overnight.  This can help get stubborn bubbles at the top of the fluid column to float up into the reservoir, and our of your hair.

[He Man]

on a side note, do not grab the clutch while you are still installing the new slave. I know its hard not to. but your only shooting yourself in the foot.

[mitt]

I takes a lot of bleeding.  For me, doing it without a vacuum tool, it took about an hour, and 1.5 bottles of fluid.

mitt

[fulltilt]

One trick.  The bubbles will be near the banjo bolt, and they like to rise, right?.  They also get caught in tricky places like the upper banjo bolt, etc.     
For easiest bleeding, once assembled, Use a small C clamp to hold the piston of the new slave cylinder inside.  Fill your reservoir  Bring the slave cylinder above the handlebars with the slave bleed screw at the top of the configuration.   pump and bleed until the sponginess goes away (don't let the resv. get near empty, and don't get brake fluid on the paint). This is also a good time to lube your clutch rod and the clutch throw-out bearing surface.   When you're done, route the bled unit through and bolt in place. 
Use new copper gaskets, they're new and soft.

[Speeddog]

It's a *lot* easier if you pre-fill the slave.

Pour a small amount of brake fluid into the fitting area, then use a small wire in the hole that goes into the slave body, 'tickling' the air out.
Repeat until you can't get any more bubbles to come out, meaning that you've then filled the slave.
Install the slave.
Put a wrench and hose on the bleed fitting at the slave.
Pump the lever a couple times, hold it in, then crack the bleed fitting open to let the air out.
Close the bleed fitting, and release the lever.
Continue doing this until no more air comes out.
Make sure to keep an eye on the fluid level in the reservoir, refilling as necessary.

Pre-filling calipers helps in the same way.

It takes some time to pre-fill, but it more than makes up for it in less bleeding time.

[Howie]

When I changed my slave I filled the new one first, then changed the line quick enough to prevent the master reservoir from emptying.  Bleeding was a snap.

[Mash]

Well, when I replaced mine, I didn't do anything fancy.  After reassembly, I bled the new slave a few times, then the master cylinder.  I repeated that process a few times and was done with it. (I kept the reservoir filled and closed tight)  If anything, I wish I had a bleeder valve on the master cylinder, but just undoing the banjo works fine. (a little messy though)

[He Man]

When I changed my slave I filled the new one first, then changed the line quick enough to prevent the master reservoir from emptying.  Bleeding was a snap.

if you keep the cap ontop, the master shoudlnt empty, once a little bit starts to drip out, it creates a vaccum and should stop immediately.

[MAXdB]

Thanks for all the help guys.. I just finished and I THiNK it's done correctly.

One question though, if the first 1/2 inch or so of travel of the clutch lever doesnt seem to do much (but the rest of the distance pulled moves the clutch plates just fine), is that a sign of "sogginess" from air in the lines or is that just a normal result of the larger piston size?

[Slide Panda]

Maybe a little column a maybe a little column b.  With the larger slave piston, it is going to require more lever travel to move the slave piston a defined amount.  But it's also possible there's still a little bit of air in the system.  Like folks of said, bleeding the clutch after a job like this can be a real PITA and there can be air stuck up all over.

Another go at bleeding can't really hurt... But if your clutch fully disengages and you have no problems shifting/finding neutral then you could probably skip a 2nd bleeding session.

[Gimpy]

Maybe a little column a maybe a little column b.  With the larger slave piston, it is going to require more lever travel to move the slave piston a defined amount.  But it's also possible there's still a little bit of air in the system.  Like folks of said, bleeding the clutch after a job like this can be a real PITA and there can be air stuck up all over.

Another go at bleeding can't really hurt... But if your clutch fully disengages and you have no problems shifting/finding neutral then you could probably skip a 2nd bleeding session.

Air in the system can be why it's so difficult to find neutral??  I have had that problem ever since I installed my slave.  I didn't think it was air cause the lever felt firm and I had bled the bejeaus out of the thing.  I have been riding around for a year with it this way.   

[the_Journeyman]

Possible Gimpy.  When my slave was leaking, I had more trouble finding neutral than after the replacement & bleed.  The leaky slave was allowing air into the system making causing me to not be able to put as much pressure with the slave.  After changing it over, I have very little free movement of the clutch lever and finding neutral is fairly easy.  It's easier if I'm very slightly moving forward too ~

JM

[Slide Panda]

Possible Gimpy.  When my slave was leaking, I had more trouble finding neutral than after the replacement & bleed.  The leaky slave was allowing air into the system making causing me to not be able to put as much pressure with the slave.  After changing it over, I have very little free movement of the clutch lever and finding neutral is fairly easy.  It's easier if I'm very slightly moving forward too ~

+1.  I had a leak at my slave and it made getting into neutral a PITA.  A leak and air in the lines can have a lot of the same symptoms.  THe most important being that all the pressure you exert at the master doesn't make it to the slave.