New clutch slave, now clutch does not work..help

[ShoelessJoe]

-New Sigutech clutch slave installed, system bled throughly, clutch does not engage
-Checked installation and everything seemed good
-Bled system one more time thoroughly (should have mentioned that I am using 5W fork oil), still not working
-Removed sigutech slave and re-installed OEM with no results
-No leaks visible

Fairly confident that it is not a slave or a bleeding issue at this point. The fork oil is different from what I used prior, but there are plenty of threads on here about using it with no issues.

So what have I screwed up? Where do I go from here? Pull the pressure plate off and look around? Not sure how I could screw something up this easily.

[AustinJake]

I just replaced the slave piston on my Husky. Does your lever feel good, like it is pressurized and moving the piston? Did you bleed the system by forcing the fluid up from the slave to the master cylinder?

I am using Acura ATF and mine works perfectly, so I don't doubt your fluid choice at all.

[geometrician]

I'm gonna take an educated guess & suggest the ball bearing is missing.

It goes between the clutch push rod and the slave cylinder piston.

Part of #37 in the KTM parts book. it may be (usually is) stuck in the grease of the slave piston, or perhaps on the ground now. Most bikes have them, it's a common thing to overlook.

If not, it's bleeding. SO many customers have brought me bikes "Oh, it's bled perfectly, no air, etc..." when it fact it isn't.

good luck

[dlrides]

When I installed the Oberon, the ball, unknowingly fell out. Found it the next day, problem solved.

[ShoelessJoe]

Looks like there is a bearing in both slaves. I'll try pushing the fluid up from the bottom and see if that helps.

[baloneyskin daddy]

Not sure I understand what you;re saying. I think you mean the clutch won't disengage as in when the lever is squeezed the bike will stall out when put in gear. Try putting a c-clamp on the slave when pump bleeding and the lever should get rock solid.

[AustinJake]

Originally Posted by ShoelessJoe

Looks like there is a bearing in both slaves. I'll try pushing the fluid up from the bottom and see if that helps.

I spent an hour trying to do it my lazy way, just pump the lever and watch the bubbles, finally got a cheap vet syringe from Tractor Supply, and some 1/4" clear tubing (very tight fit on the slave and the syringe, but a tight fit is needed), emptied the master, and pumped the entire system full from the bottom up, still had a few bubbles to deal with.

[ShoelessJoe]

Not sure what is going on, but after repeatedly bleeding the system thoroughly (pushing up from the bottom with a syringe) I had no luck with the Sigutech. Put the OEM back on, bleeding in the same method and the clutch works properly again.

Both slaves had a ball bearing visible in the piston, so I am fairly confident I did not lose it any where. Measured the depth of the piston and found the Sigutech one was slight deeper (1-2mm). No idea if this makes any difference, but it seems like it would. There was never any good resistance in the clutch action with the Sigutech on it.

Got the slave from KTM twins, so I guess I'll call Ron up and see what he can do.

Thanks for all the help.

[Buscapé]

Sigutech, that's the Hosi-stuff, isn't it ? They're a pain to bleed properly, so I'm pretty sure it's a bleeding problem. I tried to install my Hosi from my 2006 to my 2012 Adv, and I spent almost 2 days fooling around trying to get it working. Finally I was able to bleed it properly by holding the slave on its side, plunger faced down, and tapping it gently. Thus we were able to get out a very persistant bubble of air, located on the outward end of the plunger shaft. It's a construction hickup, once properly bled these slaves are very reliable...

[ShoelessJoe]

Originally Posted by Buscapé

Sigutech, that's the Hosi-stuff, isn't it ? They're a pain to bleed properly, so I'm pretty sure it's a bleeding problem. I tried to install my Hosi from my 2006 to my 2012 Adv, and I spent almost 2 days fooling around trying to get it working. Finally I was able to bleed it properly by holding the slave on its side, plunger faced down, and tapping it gently. Thus we were able to get out a very persistant bubble of air, located on the outward end of the plunger shaft. It's a construction hickup, once properly bled these slaves are very reliable...

That's probably it. Never thought of pulling the thing off and bleeding it that way. Wasted enough time on it this weekend, I'll give a shot again later in the week.

Thanks

[kingoftwins]

Hey guys.

Thought I would chime in here and see what I could do to help with this situation. Pulling it off and getting it to burp is a good idea. In the past you would be surprised at the crazy things we had to do in order ot get brakes bled. Sometimes there is a bubble of air that is stuck for some reason when bleeding new systems that takes exactly that. Pulling it off and putting the unit in a different configuration then what it is normally supposed to be in for that bubble to get past the blockage. We've used every word in the book trying to figure things like that out. We haven't had any issues with the Sigutech but definitely not going to be the one who says that hasn't happened to other customers who didn't let us know about the situation. Please keep me in the loop and let me know how it goes. With regards to the ball bearing that will need to be in place for the clutch to work correctly and Sigutech does require you to re-install your stock unit in their clutch slaves. I hope that helps.

Originally Posted by ShoelessJoe

That's probably it. Never thought of pulling the thing off and bleeding it that way. Wasted enough time on it this weekend, I'll give a shot again later in the week.

Thanks

[KTMADV]

I took me about 8 times bleeding it to get the air out.

[Deuce]

A trick I use is to secure your clutch or brake lever against the handlebar with a rubber band or clamp and just leave it over night with the cover off the master cylinder. The air will eventually bleed off while you're having a nice restful sleep.

[Head2Wind]

Clutch slaves can be a major PITA to get bled. You might try unbolting it from the engine to allow access to the piston to compress it with pump pliers or a C clamp to force any air out of the piston well. Several strokes of the slave piston should clear any air out.

[ShoelessJoe]

Originally Posted by Head2Wind

Clutch slaves can be a major PITA to get bled. You might try unbolting it from the engine to allow access to the piston to compress it with pump pliers or a C clamp to force any air out of the piston well. Several strokes of the slave piston should clear any air out.

I finally got it done. Pulling the slave off and clamping the piston seemed to be the key. That and having about five hands. Had to recruit the kids to help.

Ron, thanks for the follow up via post and emails.

Now it just have to sort out the other problem that appeared during the test ride. I'll post that one under the tuneEcu thread.

Edit: I have to say that there is a big improvement in the clutch. What I thought was an already smooth shifting bike is even better now.