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Discussion Starter #1
Good afternoon All,

Has anyone else experienced problems after installing the Evoluzione slave ?
I installed one and now I cant get the clutch to disengage completely.
Followed the instructions ,back bled it at the master cylinder bled it again and again now its unrideable poor shifting cant find neutral creeps forward with the clutch all the way in.

The original slave cylinder was corroded and leaking thats why I upgraded.
one thing I noticed was the adjusment screw in the lever was all the way in dont know if that has anything to do with it.
The master is the stock coffin type dont see any leaks

Any ideas ?
thanks






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Slave cylinder

Is the slave the 30,mm size??
Also...back the screw at the lever out a bit...that should make a difference..
Mike
 

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There should be a bit of play before the lever engages the plunger on the master. If that screw is all the way in it might be pushing the plunger in and there for not enough travel to fully disengage the clutch. I have the Evoluzione slave and coffin style masters. Big difference and have had no problems.
 

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Discussion Starter #5
There should be a bit of play before the lever engages the plunger on the master. If that screw is all the way in it might be pushing the plunger in and there for not enough travel to fully disengage the clutch. I have the Evoluzione slave and coffin style masters. Big difference and have had no problems.
Thank you,
I backed the screw all the way out then took off the slave and pushed the piston back into the slave hoping that it would push the master piston back
no luck on that one.........
Thinking that theres a problem with the master like i said the slave was corroded this bike came from the bay area and lived outside so in not suprised to find damage
It just adds to the fun of ownership!
 

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It sounds like the piston in the slave cylinder is hitting the engine case before the clutch is disengaging. Nothing you can do at the master cylinder, or by bleeding the system will correct this.

On mine, it looked like the radiused end of the release rod was such a small radius that it was sticking way too far down into the bearing located down inside of the slave cylinder's piston, effectively shortening the release rod to where it would no longer release the clutch before the slave cylinder's piston hit the case. I wound up shimming behind the bearing inside of the piston in the slave cylinder, effectively lengthening the release rod.
 

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Discussion Starter #7
It sounds like the piston in the slave cylinder is hitting the engine case before the clutch is disengaging. Nothing you can do at the master cylinder, or by bleeding the system will correct this.

On mine, it looked like the radiused end of the release rod was such a small radius that it was sticking way too far down into the bearing located down inside of the slave cylinder's piston, effectively shortening the release rod to where it would no longer release the clutch before the slave cylinder's piston hit the case. I wound up shimming behind the bearing inside of the piston in the slave cylinder, effectively lengthening the release rod.
Thanks Higgy,
Took a look at the bearing and rod,all semms to be well if I'm understanding your post.
My pushrod has a larger diameter than the bearing although the bearing seems very loose in the slave bore.still have a huge amount of free play at the lever before the clutch starts to disengage but with the lever in all the way its not fully disengaged. still thinking somethings not right with the master.
Still confused.

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93 900 ss
83 suzuki gsx 100sz katana
74 Porsche 911 carrera
 

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You can still take that free play out by shimming behind that bearing in the slave piston bore. Even if the radius on the end of the release rod is a good deal larger than the hole through the bearing, so that it does not protrude too deep into the bearing, the hole in the piston may have been bored too deep.

In other words, whatever the cause, the net affect is the same - all of that slack you are feeling at the lever is the piston and release rod moving before the release rod starts to press against the pressure plate. If that movement is mostly taking up slack between the release rod and the pressure plate, the piston will bottom against the case before the rod has gone far enough to release the clutch. The piston can only move so far; if most of its available travel is spent taking up slack between the release rod and the pressure plate, it will never release the clutch.
 

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Re-Bleed! sounds like you have air in the line and its not pushing out enough?

Bench bleed it then put it back on and bleed once more? Pump the lever is all you need to do , mine did the same thing.
 

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Discussion Starter #10
You can still take that free play out by shimming behind that bearing in the slave piston bore. Even if the radius on the end of the release rod is a good deal larger than the hole through the bearing, so that it does not protrude too deep into the bearing, the hole in the piston may have been bored too deep.

In other words, whatever the cause, the net affect is the same - all of that slack you are feeling at the lever is the piston and release rod moving before the release rod starts to press against the pressure plate. If that movement is mostly taking up slack between the release rod and the pressure plate, the piston will bottom against the case before the rod has gone far enough to release the clutch. The piston can only move so far; if most of its available travel is spent taking up slack between the release rod and the pressure plate, it will never release the clutch.
Thank you Higgy ,
Already bought some shims giving it a try.think i bled it enough pumped a full quart thru it no air.
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93 900 ss
82 Suzuki gsx 1000s katana
74 porsche 911
 

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Thank you Higgy ,
Already bought some shims giving it a try.think i bled it enough pumped a full quart thru it no air.
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93 900 ss
82 Suzuki gsx 1000s katana
74 porsche 911
Do you have the Clutch cover off ?
Shim the bearing so the Rod is longer? :confused:

Just upgraded mine to New and the bearing was bad, I never heard of shimming. Great idea!
 

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Great Idea Mr.Higgy, because you would have to shim the Clutch? Plates?
 

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Great Idea Mr.Higgy, because you would have to shim the Clutch? Plates?
You shouldn't even have to touch the clutch.

I think the hole in the Evolutione slave cylinder piston into which the clutch release rod fits is simply bored too deep. It appears to be borderline, where it works fine on some bikes but is too deep for others. Fortunately, they use a bearing inserted into that bore, so we can easily adjust the "working depth" of that hole by simply shimming behind the bearing. No fuss, no muss, don't have to mess with the clutch, and it takes all of about ten minutes to take the slave cylinder off and shim under that bearing. I just use a flat washer of the appropriate size on mine. It only took one and the clutch was once again releasing normally.
 
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