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Jay_G
13-10-2008, 04:45 PM
So my clutch is slipping, (duh hence the thread title)

it has done since i built the engine (Gt750).

First used the plates that came with the bike, used car engine oil as i was planning on dumping it a few times to make sure it was clean since i built the donk in my garage put it all together and it slipped when came onto power.

a few months later i had a spare set of fibres(used) and steels, so i sandblasted the steels and gave the whole lot a clean in a parts washer. soaked the fibers in bike oil(repsol) and put all together with new ebc springs. made it better but still slipped, i also pissed off the actuating rod through the engine and put on a gpz cover since i couldnt get a new cable for the old setup.

it slips more when cold and the engagement feels varied sometimes, it also slips a bit more although i am not entirely sure if i tip it into a rh corner and try roll on the power.

adjustment is fine,

So the plan is am going to order a set of new EBC fibers and soak them for min 24 hrs, blast another set of steels, and clean up the grooves on the basket, although they didnt look to bad.

Any other things i should be looking at? is there any specific bearings that can be worn or thrust washer or anything stupid like that that can wear out and cause these problems?

also tips on a good oil and weight to use in a slightly grumpy aircooled kawasaki?

BANDITROD
13-10-2008, 05:14 PM
i reckon grooves in the basket is your problem mate but thats just my opinion so lets see what everyone else has to say

Cruisecontrol
13-10-2008, 05:17 PM
I say:

Car oil + Motorcycle = Bad.

New friction plates + Synthetic bike oil = Win!

Jay_G
13-10-2008, 05:35 PM
Is there anything that can be done to "blueprint" a clutch? i know they can be "banded" but i dont think i am putting out enough power to warrant it. would it be benificial to polish the contact surfaces on the basket that i file down of just straighten them out and give them a hit with some fine emery?

Benz
13-10-2008, 07:58 PM
My Gpz turbo is in need of new clutch plates too, but for the moment [the Wet is comin, plenty of time for maintenance then..] I just added another steel to the pack. Stopped all the slipping immediately...
Put the extra steel in first,then another steel, fibre, steel, fibre, blah blah. It will make the pack a few mil thicker, and could solve the slipping. Not recommended for a long time, but it will tell you if you need to buy new fibres, or not.......

Jay_G
13-10-2008, 08:25 PM
from what i have read, the turbos actually have a different clutch pack in them, thinner fibers and possibly steels with a total of 8 fiberes instead of 7 in the standard model.

EBC do a "race" kit for the turbo too kevlar plates or some such.

Shadowzone
13-10-2008, 08:57 PM
quote:Originally posted by Cruisecontrol

I say:

Car oil + Motorcycle = Bad.

New friction plates + Synthetic bike oil = Win!


I agree completely. What kind of car motor oil did you use? Anything with friction modifiers will cause clutch slippage and some additives in oil will do the same thing as well.

In addition to the new clutch plates You will also need to completely remove any of the old oil out of your engine. This can be done in a number of ways. One of my favourites is the Kero method. I'm not going to advise you use it or post a how to as if you do it incorrectly you'll be buying a new motor. Generally new cheap homebrand type oil will suffice for your purposes. fill it up (new oil filter) go for ride, drop oil. repeat several times. Replace with quality oil and filter.

Start enjoying motorcycle again.

jmw76
13-10-2008, 09:01 PM
I have found on my GSXR clutch that the plates eventually cut into the basket and hub. This results in them sticking and not closing up correctly. The result is clutch slip.
T solved the problem by simply runing a file up and down the groves of the basket and hub just to clean them up a bit.
The plates now slide freely and no more slipping.
A cheap fix.
Cheers

Benz
14-10-2008, 12:59 AM
quote:Originally posted by Jay_G

from what i have read, the turbos actually have a different clutch pack in them, thinner fibers and possibly steels with a total of 8 fiberes instead of 7 in the standard model.

EBC do a "race" kit for the turbo too kevlar plates or some such.

I'll stick with original plates, you can still get them. Any kind of abrasive in the plates [ala kevlar fibre...] ends up spinning through the turbo bearings, severely shortening it's fun factor.
The turbo has essentially the same clutch, just its crank to clutch speed has been bumped up to handle more output.