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Discussion Starter · #1 · (Edited)
I had to replace a clutch at the racetrack last week and felt a drastic increase in engine braking. I thought maybe the fibers would break-in and slip a bit more but that didn't seem to be the case after two solid days of riding. So my stack height must be too tall.

Does anyone have advice on how to decrease engine braking and increase the slip with OEM clutch components? (I have a Bauce racing flash and I cannot adjust EB via the ECU, so it must be done mechanically)


I was thinking I could replace one or two of the #8 steels with #7 steels?

Here is the fiche:



Any advice is appreciated. Thanks
 

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Discussion Starter · #4 ·
Did you measure the stack width to ensure it’s not too tall?
I have not...and I did see that in the service manual. I was at the racetrack when I installed it and didn't have a way to measure. I think I am going to change a steel or two this weekend so I will be sure to measure the stack height.

I followed the Fiche exactly so it should be correct. It's possible the stack was adjusted before I owned the bike, or maybe it was worn out and I just liked the feel of it worn out. So maybe the stock EB is just too much for my liking.
 

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Venom X/O
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I have not...and I did see that in the service manual. I was at the racetrack when I installed it and didn't have a way to measure. I think I am going to change a steel or two this weekend so I will be sure to measure the stack height.

I followed the Fiche exactly so it should be correct. It's possible the stack was adjusted before I owned the bike, or maybe it was worn out and I just liked the feel of it worn out. So maybe the stock EB is just too much for my liking.
I actually had someone from the forum reach out about clutch drag and they had an issue with gouging on the boss and assembly, which required filing to get it to stop grabbing the boss. I’d measure the stack width becuase it may just be sticking to the boss and not slipping correctly. Could be the stack not allowing a disengagement. Do you have the service manual for replacement or only the microfiche for a picture reference ?

throw it on the rear stand and put it in first. Pull the clutch lever and see if the rear is still spinning like crazy.
 

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Venom X/O
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Starts on page 396
 

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Discussion Starter · #7 ·
I actually had someone from the forum reach out about clutch drag and they had an issue with gouging on the boss and assembly, which required filing to get it to stop grabbing the boss. I’d measure the stack width becuase it may just be sticking to the boss and not slipping correctly. Could be the stack not allowing a disengagement. Do you have the service manual for replacement or only the microfiche for a picture reference ?

throw it on the rear stand and put it in first. Release the clutch and see if the rear is still spinning like crazy.
I've got both the fiche and the service manual available.

I'll check out the boss situation. Thanks for the reply
 

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Venom X/O
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I've got both the fiche and the service manual available.

I'll check out the boss situation. Thanks for the reply
Wish you luck. There’s only a few things that’ll keep it grabbing. A missed bushing, wrong stack thickness, out of adjustment on the lever, or potenally the boss being gouged and not letting the plates slide correctly. Outside that there isn’t much. Let us know if you find something different.
 

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Astronomer not Astrologer
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It was an r6, and our issue was with the clutch not disengaging with the lever pulled in. The clutch boss and the basket had been warn down where the steels and friction plates ride on them.

You can see where I filed one of the teeth, vs a few that were untouched where you can see how bad it was.

The filing didn't "fix" the problem 100% but it probably got back 85% of the original feel. A new boss and basket seem to be not available.
 

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Astronomer not Astrologer
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Ps when we put new plates in. We had to swap the first steel to get the right stack height, as the oem generic stack height was too thick, so definitely watch out for that. A cheap set of calipers from harbor freight will do the job nicely.
 
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I guess it would be the stack height because looking at various pictures of it, it looks like there needs to be some clearance between Part No.12 and Part No.9 otherwise the pressure plate can't ride up the ramps (it will hit Part No. 12). It is hard to tell from the pictures but if the stack height is too high it will move the pressure plate out further (closer to Part No.12) and won't allow it to move out (or not move enough) when it rides up the ramps in the clutch basket.
I'd say the manual won't tell you what clearance should be there between the 2 parts because they assume you will measure the stack height and get it correct so it won't be a problem. Hope that helps.
 

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Astronomer not Astrologer
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I can report that my buddy's clutch is way way way way better. His slipper clutch actually unlocks now, and the bike is way more stable on down shifts.
 
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