Clutch Drag: How much is too much?

[Toast]

Hello

I recently installed new plates and fibres in my 06 R6 race bike’s clutch

Took it for a brief ride on and it feels great, first gear selected easily though with a solid bump, gear changes are fine, power wheelies in 2nd without even wanting to, but…

When on the stand, in gear, clutch lever pulled in (the cable is well adjusted), the rear wheel spins quite furiously, such that I can’t stop it with hand or foot.

The rear brake will stop it without stalling the engine, and there was only a mild creep with the wheels on the ground and the bike in gear (lever pulled).

I’ve set the stack height at 42.8mm (manual states 42.4.43.0mm). I did use a thicker first plate (by 0.3mm) to get it sitting higher in the range, as I was advised that this is desirable for optimal power transfer

I pulled it apart and made sure that all of the plate and fibre surfaces were well oiled, re-assembled, fired up, and the same thing with the rear wheel spinning very fast on the stand

As stated, it rides great, but is having this much drag on the clutch going to cause it to wear prematurely? Or can it cause some other ill effects? I imagine that the slipper function would be slightly less smooth although I didn’t really notice this in my short ride on it

Thanks for any advice on this!

[BASS-TREBLE]

Are you sure that it didn't do it before?

Mine does it a bit too, it's due to the fact that we have wet clutches, meaning that there is always slight connection between the plates due to the engine oil, which transfers a little power.

The fact that you say you can't stop it with your hand is probably due to the fact that you let it build up momentum. If you held it with your hand before it speeds up I'd say it's not that hard to stop, I wouldn't try though =D

[Toast]

Hey mate, nah, I can’t say that it didn’t happen before. It may have done, as I remember there has always been a pretty solid click in to first gear.

I think you’d be right, I could probably hold the wheel at the start, when I put it in to gear, but the fact that it gets up so much pace and so quickly just made me think that it is maybe dragging too much?

I was thinking maybe having the plates too close together would mean they’d get less lubrication between them, and thus maybe, possibly, hot spots that could cause warping?

[imdying]

Do you have any actutator adjustment down the bottom? It's often neglected on bikes that do. Sorry if that's a teach you to suck eggs question, but worth asking.

[Toast]

Do you have any actutator adjustment down the bottom? It's often neglected on bikes that do. Sorry if that's a teach you to suck eggs question, but worth asking.

Do you mean the cable adjustment at the bottom? Near the arm that goes inside the case and pulls the pressure plate away from the clutch stack? If so, I have tried adjusting all the free play out of the cable, so that the arm pulling the pressure plate gets max movement, and it still drags.

Or do you mean some kind of adjustment inside the clutch? If so, then the only reference to adjust the actual clutch in the manual is playing with the stack height via different thickness plates

Or is there something I’m missing?

[White trash]

Dumb question, got the correct oil in it?

[Toast]

Dumb question, got the correct oil in it?

No question is too dumb when I'm involved, Jimmy:

I believe so, Maxima full synthetic 10w/40

[White trash]

Tell ya what, my GSXR rear wheel would spin on the stand like that and was hard to stop untill the engine and oil had a heap of warmth in it.

[imdying]

Do you mean the cable adjustment at the bottom? Near the arm that goes inside the case and pulls the pressure plate away from the clutch stack? If so, I have tried adjusting all the free play out of the cable, so that the arm pulling the pressure plate gets max movement, and it still drags.

Or do you mean some kind of adjustment inside the clutch? If so, then the only reference to adjust the actual clutch in the manual is playing with the stack height via different thickness plates

Or is there something I’m missing?

Not sure, haven't seen that particular setup, but here's a general clutch cable adjustment guide.

A clutch cable setup generally has 4 places where changes can be effected:
- The push rod free play adjustment at the actuator
- The outer cable bottom adjuster
- The outer cable top adjuster
- The clutch lever span adjuster

The purpose of each of these items is:
- The push rod free play adjustment at the actuator is used to ensure that the clutch actuation mechanism (i.e. the cable and lever) aren't holding the clutch on slightly
- The outer cable bottom adjuster is used to adjust most of the free play from the cable
- The outer cable top adjuster is used to fine adjust the free play in the cable
- The clutch lever span adjuster has no affect on the clutch engagement adjustment, it's merely a a comfort thing for your hand

To adjust your cable actuated clutch, you should do it in this order:
- Remove the cable from the actuator and clutch lever
- Loosen the actuator adjustment lock nut and adjust the push rod free play so that there's minimal clearance. When you work the arm, there should be about a little jiggle before you feel the actuator work up against the push rod, then tighten the lock nut and recheck the adjustment
- Attach the cable at both ends
- Wind the lever fine adjuster all the way in
- Use the lower cable outer adjuster to take up most of the slack in the inner cable
- Now use the fine adjuster up the top to remove all but a little slack in the inner. A little slack is important, as it stops the lever from pulling the clutch on slightly. Tuning the slack in each part of the system is really the difference between a well adjuster and horribly adjuster cable


Once you've done that, you can eliminate that are your base problem. I don't think it is your problem, but it's cheap and easy to check. Make sure you take this opportunity to lube the cable, and and pivot points, and where the cable inner sits in the lever. Generally a completely misadjusted cable manifests itself as a bike that crunches into gear, but check it anyway.

[k14]

You should always leave a little bit of play in the cable, I was told 5mm at the lever (measure the gap that the lever makes with the mount when the cable slack is taken up). Have you ridden it yet? It will wear slightly in the first ride and could free up then.

[Toast]

Tell ya what, my GSXR rear wheel would spin on the stand like that and was hard to stop untill the engine and oil had a heap of warmth in it.

Interesting. I did try it after a quick ride, so well warmed, and it still spun, though not as bad. Gav told me to put the plates in all the same way with the sharp edge facing the clutch, did that, still grabbing, but haven't tried it like that when it's warm yet.

Not sure, haven't seen that particular setup, but here's a general clutch cable adjustment guide.

Good info, mate, thanks! I don't think that there's any adjustment at the actuator on my bike, but I'll double check tonight. Other than that, yeah, I pretty much adjusted it as you describe.

You should always leave a little bit of play in the cable, I was told 5mm at the lever (measure the gap that the lever makes with the mount when the cable slack is taken up). Have you ridden it yet? It will wear slightly in the first ride and could free up then.

Yeah I wouldn't ride it with no play in the lever, but I was just trying to see if taking all of it out would stop the dragging.

I took it for a brief ride 1 minute ride around some back streets, and it did seem to get a little better after the ride, and stamping on the rear brake a few times with lever pulled in which I read may help to unstick the plates. Haven't had a chance to give it a thorough test though.

[Toast]

Oh yeah, one other thing that I just thought of: when I got the plates, most of them had slight corrosion on them. I gave them a bit of a shine with a green steelo pad thing. Maybe the very slight roughing up of the smooth side is causing them to stick a bit more than usual?

[imdying]

Yeah, have a gander in there. Often it's accessible under a small plastic cap on the front sprocket cover (to save having to dismantle it to adjust it, as typically it's something they check/adjust during servicing). Having had the clutch pack in bits, it's likely it'll need a tweak on the free play. Give it another check after 1500kms of riding too. Or less if you're raping it on the track etc.

[Toast]

Yeah, have a gander in there. Often it's accessible under a small plastic cap on the front sprocket cover (to save having to dismantle it to adjust it, as typically it's something they check/adjust during servicing). Having had the clutch pack in bits, it's likely it'll need a tweak on the free play. Give it another check after 1500kms of riding too. Or less if you're raping it on the track etc.

I had a look in the manual and at the bike but I don't think that the R6 has such a thing as you mention.

Anyway after a couple of sessions on track, the drag is pretty much gone! Stoked!

I had a Yamaha mechanic look at it before I took it out and he found nothing wrong. Maybe the corrosion on the plates just made it extra grabby for a short time (in spite of me scrubbing them with a scotchbrite pad before installing)

Back goes like a rocket now

Cheers all for your help!