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Discussion Starter · #1 ·
Did a search but I only see the usual stuck clutches from a bike that's been sitting awhile. So I have an 04 R6, rebuilt the clutch with a Yoyodyne slipper. I've ridden it several days on the street with no problem to include a day of spirited canyon riding. I'm at a track and about the third or fourth lap the clutch pull goes extremely light and won't disengage the clutch. The bike still shifts fine between my quick shifter and slipper but I can't disengage the clutch. The cable is fine and it pulls the lever on the clutch hub no problem. It's just super light and doesn't disengage the clutch. I had the cover off and couldn't see anything wrong without pulling the plates themselves. Put the cover back on, with the bolt teeth aligned and no change. The oil is still new too from changing the clutch. Any ideas?
 

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Discussion Starter · #2 ·
Plus, no slippage at all while riding. Consistently hit +135mph on the front straight at Pueblo Motorsports Park; pulls like a thoroughbred
 

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My bike hates me
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can you turn the clutch arm by hand? I dont know much about slipper clutches but im assuming there is still a pull rod attached to the arm on the clutch cover. If thats to stiff to turn then i would also assume the clutch is fine. Is the cable still in its keeper? On my first gen at the end of the cable is a threaded portion with some nuts and if it pops out of there partially i lose most of my clutch function
 

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Discussion Starter · #4 · (Edited)
Yeah , there's still a pull rod connected to the arm and both operate just fine. I can pull it by hand and looking into the fill port I can see the rod move. The cable is seated at both ends and I can pull it manually from both ends; seems completely intact. From what I can tell, everything is fine between the lever and the pull rod - but inside the clutch at the other end of the pull rod nothing happens.
 

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Discussion Starter · #5 ·
During the install I noticed that the springs that Yoyodyne provided were shorter than stock and what the manual says. Could this be an issue?

Also, seems the clutch locked up during a downshift with the slipper slipping as it should. What could've happened there to make it stop disengaging?
 

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Mr. HER6
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I'm guessing those springs were provided for a reason. If they were too short to provide reasonable force, it would be slipping.

It sounds more like the teeth are off between the push-rod and the axle that the cable pulls on. You have taken out the slack in the cable, but if those teeth are off there is slack in the push rod. So you don't feel resistance because you're not actually pulling against the clutch springs to disengage the clutch. At least not until the end of your lever stroke, which isn't enough.

Another thought is that the stack in the new clutch is too tall. Was there a spec to measure and did you do it? There may have been extra plates like the OEM slipper clutch sets that are different thicknesses. Putting the extras in will also result in these symptoms.
 

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Meh
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Keep us updated on how it turns out. I've had similar problems with my bike, where the clutch refuses to fully disengage. Not nearly as bad as yours, but sometimes it's bad enough that it's really difficult to get into neutral and it'll stall if I'm stopped and in gear with the clutch pulled in.
 

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I ride my wife and her R6
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I'm guessing those springs were provided for a reason. If they were too short to provide reasonable force, it would be slipping.

It sounds more like the teeth are off between the push-rod and the axle that the cable pulls on. You have taken out the slack in the cable, but if those teeth are off there is slack in the push rod. So you don't feel resistance because you're not actually pulling against the clutch springs to disengage the clutch. At least not until the end of your lever stroke, which isn't enough.

Another thought is that the stack in the new clutch is too tall. Was there a spec to measure and did you do it? There may have been extra plates like the OEM slipper clutch sets that are different thicknesses. Putting the extras in will also result in these symptoms.
I tend to agree with this. Ref the link

http://www.ronayers.com/CLUTCH--C442156.aspx

If there is slack at the pivot at item 25, the pull lever, the gears at the other end of the pivot rod, item 22, push lever axle wont be able to move the push rod, item 8 enough to disengage the plates.

If this happened suddenly, you need to open up the case and inspect the parts in question to make sure they are intact.

First, I would check for slack in the lever where it hooks to the push lever (25), can you rotate the lever with your fingers? If there is significant slack, you have internal slack and you need to index 25 on the spline to take up the slack, you should not be able to rotate the lever by hand. If that doesn't work there might be a broket/worn tooth inside either on the axle (22) or on the push rod (8).
There is also a possibility that 25 has spun on the spline. With enough tension it could slip if you missed tightening the bolt clamping 25 to the spline.

There is also a possibility that the bottom of the clutch cable might have come out of item 32 in the next link. It hapend to a guy I know at the track a couple months ago on his first gen. He had the exact symptoms

http://www.ronayers.com/CRANKCASE-COVER-1--C442160.aspx

Good luck with finding the problem, that is what I can come up with. Cheers, Mike.
 

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I ride my wife and her R6
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Yeah , there's still a pull rod connected to the arm and both operate just fine. I can pull it by hand and looking into the fill port I can see the rod move. The cable is seated at both ends and I can pull it manually from both ends; seems completely intact. From what I can tell, everything is fine between the lever and the pull rod - but inside the clutch at the other end of the pull rod nothing happens.
After going through your earlier posts again, I saw (in bold red) that you CAN move it by hand. You should not be able to do this. Try indexing the lever (25) to take up this slack. This is where my money is.
 

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Discussion Starter · #10 ·
Thanks guys. I'll open her up again and look at the plates as His Own said. I'm pretty confident I had the right stack height when I installed but I'll double check.

Husbeast, there is slack in the pull lever - I can move it by hand and I can see it moving part 8, the push rod, so I know it's engaged on the spline. The curious thing is I've got the pull lever aligned with the dot on the case per the manual. If I adjust it further/tighter, I can't get the clutch cable to reach the seat on the pull lever. But I'll mess with it after I check the plates and stack height.

Thanks again for all the replies.
 

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Discussion Starter · #11 ·
The plot thickens: so I went to open her up tonight, and the clutch was disengaging just fine, as if nothing happened. So for some reason, it sticks when it gets hot ie on track.

I opened her up anyway and inspected everything. All was in order save two friction plates. When I originally installed the slipper, I replaced all the plates with new ones from Garrett. The problem is the first two stock friction plates are thinner than the rest. The kit I had from Garrett had all the same size friction plates. So just in case this matters I installed the two thinner stock plates first per the manual. Everything else was as it should be. The stack height still measured within tolerances from Yoyodyne. And the clutch still actuates like it should. Unfortunately I probably won't be able to test it hot again until my next track day on Columbus Day.

What do you guys think? Will putting the two thinner stock plates fix the hot stuck clutch? Is there anything else it could be? Obviously we won't know for sure until I hit the track, but I was wondering if there's anything else I can look into in the mean time. Thanks
 

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Discussion Starter · #12 ·
Maybe the lesson here is that the simplest solution is usually the correct one. Swapped the first two plates and got out to High Plains Raceway. During the first session it got loose again. But when I went to open the clutch again, I saw that the adjustment nut on the back of the clutch cable had backed itself off. It was still seated correctly next to the push lever assembly, though the nut was hidden behind the mounting bracket which is why I never noticed it before - I glossed over the cable adjuster since it was always still seated. So when I got the clutch cover off and back on i snugged it back up and it would work just fine for a while. It seems the adjuster nut only backed off under full throttle shifts with the QuickShifter which is why I never had a problem on the street. It's in kind of an awkward angle under the bracket but I felt like I was tightening it well enough. Anyway, I threw some locktite on it this time and now it holds.

Thanks for the help, everyone. Here's a video I made from that track day:
http://youtu.be/G3qPFDfS73A
 

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"The Dude abides .. "
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got the vid without music ?
not for nothing, but the friction plates are all the same thickness. There ARE different firctions, one goes in first, middle are all same, then outermost is different.. these have a color painted on the tab. (pink, black, brown i think). The METALS have a standard thickness that all go in first, then the OUTER 2 metals you either use standard (2.0mm) or the thin (1.6mm) or thick (2.3mm ) to adjust stack height..

yes, having the cable adjuster or cable bracket nuts come loose will affect how the lever works. :)
 
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