Clutch slip - new springs but clutch won't disengage

[whowhatwhere]

Hi all - hoping your widsom can help me out here.

Clutch was slipping at 50,000km so pulled apart the clutch - everything within spec and looked fine but replaced the friction plates anyway - problem fixed.

Now at 54,000km it's slipping again (have only been using mineral oil). Everything still looks mint and in spec so I've installed new EBC springs (which are a lot stiffer than the old ones).

I'm getting some serious clutch drag now (i.e., bike creeps forward with me on the bike, can't select neutral, plates get hot and expand so the bike nearly stalls when braking to keep the bike still).

Have adjusted the cable so that the clutch bites just before the lever is fully released - pulling the lever all the way in (I need two hands to do this as the springs are stiff!) the clutch still drags. Have also adjusted the 'worm drive' as per Haynes manual but I'm not really sure what this does?

Is there something I have missed? I'm not really sure why stiffer springs stop the clutch from fully disengaging when the old ones didn't have this issue and there's no warped plates or notches on the basket.

I'm temted to try the old springs again with added washers to increase the tension, but would like to fully understand the current problem before I woos out and go back to the old ones!

Chur

Bike: '98 GSX750F

[sugilite]

Did you soak the new plates in oil before putting them in?

[whowhatwhere]

Did you soak the new plates in oil before putting them in?

Yeah soaked them overnight.

[bogan]

Is there any part of the assembly that might not be correctly seated, and pushing the plates out or something?

Also, probly not relevant, but I know with the bros's there are aftermarket clutch springs but you only run two of them, not all four...

Just seems a bit strange it takes that much force to pull it all way in.

[whowhatwhere]

Is there any part of the assembly that might not be correctly seated, and pushing the plates out or something?

Also, probly not relevant, but I know with the bros's there are aftermarket clutch springs but you only run two of them, not all four...

Just seems a bit strange it takes that much force to pull it all way in.

I'll have to have another look. I did think about running 2 old with 2 new springs but thought that might promote plate warp?

I guess I'm trying too work out if it's the springs or not. If I can feel the clutch 80% disengage by pulling in the lever, the remaining drag must be some other factor?

[bogan]

Yeh, that'd be my thoughts too. Unless, the reamaining 80% is flexing other bits like the cable, while the clutch 'hub' bit stays in the same place.

[whowhatwhere]

New springs were about 2mm longer than the old ones which did seem a lot

[Akzle]

hate to ask the obvious... but is the cable adjusted properly...
generally done by "lever freeplay" rather than "clutch engages at 80%" and difinitely "I need two hands to do this" rings alarm bells.

"worm drive" is throwout that actuates the pushrod which splits up the clutch plates.

your manual should read something like
"slack cable completely by winding in fine adjustment at lever and coarse adjustment at clutch cover

use box wrench to loosen lock nut on worm drive

wind in central screw with screwdriver until resistance is felt

tighten locknut

adjust lever freeplay"

generally freeplay=
wind adjustment on clutch cover until gap is ~10-15mm, then lock adjustment.

(gap is determined by pulling lever until resistance is felt and measuring distance between stock/hinge and lever/stop)

wind fine adjustment at clutch lever to bring freeplay down to 2-5mm and lock adjustment.


=problem solved?

[jonbuoy]

You sure you have the right number of steels and friction plates in?

[spanner spinner]

do the clutch ajustment as akzel reply, if this makes no diffrence pull that clutch cover off and check the play in the clutch basket. Suzuki's use a two part clutch basket rivited together, if there is excessive play between the two parts you get faults just like you have discribed as it dosen't lock up or disengage correctly.

[spanner spinner]

I have just reread your orginal post and if you have to pull the clutch cover off check the pressure plate as it may have been warped by the heaver springs by pushing the center out where the clutch rod works on it. Check across the face of the plate with a straight edge (ie steel ruler) to make sure it's flat, also work the clutch lever with the clutch assembled to see if the center where the clutch rod is is pushing out with out moving the rest of the plate, you may have to go back to the old springs if it is.

[whowhatwhere]

Positive the cable is adjusted correctly - adjusted just as you described as per the manual.

Def the currect number of plates - was also ok beforehand.

With the cover off and working the clutch it's not moving freely around the whole circumfrence, looks to be sticking along one of the edges on the basket, which was making it stiff at the lever. Pulled all of the plates and reinstalled and they're moving freely. Plates still dead flat so can't see that I've damaged anything. The edges on the basket actually look ok to me but will smooth them up a bit and reinstall.

Need to get my torque wrench calibrated as I snapped the head off one of the spring bolts so will replace all four as a precaution in case I've stressed the others too. Just got to wait for the postman!

Old bikes eh!

[CookMySock]

Which oil in the bike exactly?

[SuperSonic]

I am having to replace my clutch as well, different problems as yours and different bike, well by year, but I talked to alot of US guys races and road riders about aftermarket clutch vs OEM clutch, manily the EBC aftermarket one with stronger springs in it too. Sounds the same as yours. ANyway they all highly recommed sticking with OEM clutch as many have had to replace the fibres again within 10,000kms. Even thou the stock clutch is way more expensive they pay for them selves in the long run.
The stock fibers are high quality and stiff, and strong have contact patches that are really almost razor sharp. and they have space/gaps between each other. the EBC doesnt. its one continuous fiber material. it feels a lot softer and this making them not last as long, also opening them up to faster wear if clutch sets are out a little.

I suggest going back to stock fibres and springs.

My 2 cents worth. Good luck

Also side note one of the guys had same kind of problem as you, he removed EBC springs put old stock springs back in as it would not disengage, perfect, but like spanner says you migh thave warped the steel now.
Stiffer springs not, all EBC have done is make them longer like you posted, this makes them stiffer.

[CookMySock]

all EBC have done is make them longer like you posted, this makes them stiffer.Potentially, they will also bind up at full compression, causing the clutch to tow.

I think its got the wrong oil in the engine.