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Clutch not disengaging - why?

Mon Nov 26, 2007 5:12 pm

I've just got home from a weekend trip to Lakes Entrance and back, and most of the way home the clutch has been playing silly buggers. Hard to get the bike into neutral, hard to change down gears, and it's not disengaging the drive (sitting there at lights with lever pulled in and the bike moves).

Might it need:

A top up and a bleed,
A top up,
A bleed,
A leak fixed?

I know it's hard to diagnose over the internet but has anyone got any bright ideas?

The lever doesn't pull in anywhere near as much as I'd like either, what else can go wrong with clutches that I can check?

Cheers.

Re: Clutch not disengaging - why?

Mon Nov 26, 2007 5:46 pm

i'd say a top up of clutch fluid (same as brake fluid) and a bleed.

if problem persists see your doctor...

oh i mean check for leaks around master cylinder.

if that fails maybe some seals are dead in your master cylinder. :?

Re: Clutch not disengaging - why?

Mon Nov 26, 2007 5:47 pm

im guessing they have a hydra clutch....

cheapest and easiest steps are what u said- check fluid level, check its well bled and the fluid hasnt broken down...

then the adjustment..this im not so sure of....

failing that...u may need to pull it apart to have a look at the plates etc...

Re: Clutch not disengaging - why?

Mon Nov 26, 2007 6:20 pm

Bogan wrote:I know it's hard to diagnose over the internet but has anyone got any bright ideas?

Cheers.

Thomas Edison did.

Re: Clutch not disengaging - why?

Mon Nov 26, 2007 6:58 pm

Also check for leaks at the slave cylinder end. More likely than master cylinder leaks in my experience. Easy things to rebuild.

Re: Clutch not disengaging - why?

Mon Nov 26, 2007 8:13 pm

Sounds like the clutch isn't disengaging correctly. This would assume the mechanism isn't pulling the plates apart. Also, you say the level doesn't travel as far as usual? That does not match a fluid issue. Like a brake, when there are issues with the with the fluid the lever travels right to thebar with less pressure. I'm guessing your lever feels stiffer? Either you have a sticky push rod or you'v been clutch up monos/burn outs and have fused a plate. Might be time to take the outer housing off and see if the push rod is stuck - usually just has dirt on the rod, a quick clean up and grease and it's business as usual.

Re: Clutch not disengaging - why?

Mon Nov 26, 2007 9:01 pm

photomike666 wrote:Sounds like the clutch isn't disengaging correctly. This would assume the mechanism isn't pulling the plates apart. Also, you say the level doesn't travel as far as usual? That does not match a fluid issue. Like a brake, when there are issues with the with the fluid the lever travels right to thebar with less pressure. I'm guessing your lever feels stiffer? Either you have a sticky push rod or you'v been clutch up monos/burn outs and have fused a plate. Might be time to take the outer housing off and see if the push rod is stuck - usually just has dirt on the rod, a quick clean up and grease and it's business as usual.

You could be right here I did about 10km of gravel on Sunday it might just be full of crap. Time to enlist some local help to pull some crap apart (well more accurately to be able to put it back together) me thinks.

Ta muchly people.

Re: Clutch not disengaging - why?

Wed Dec 05, 2007 10:06 am

Sounds like a sticking clutch master or slave (I bet slave). Not much on the mechanical side that will cause this.

You have a PM on CanberraRiders.

Regards, Andrew.

Re: Clutch not disengaging - why?

Thu Dec 06, 2007 6:22 pm

O.K, just had Bogan out here, flushed and bled clutch hydraulic system and removed slave cyl, hydraulics functioning normally, no leaks (but horrible filthy fluid flushed!). Pushrod is smooth and free in it's bore, but it is hitting something solid at the other end. The end of teh pushrod is not mushroomed or worn in any strange manner. The clutch will almost disengage, but it still is engaged (to the point of a stall when engaging a gear).
Now, looking at the diagram:
http://www.ronayers.com/fiche/400_0223/ ... rent=13460" target="_blank" target="_blank
it seems it has a star spring (leaf spring pn 39130). I know on the GTR's of a similar era, these springs were prone to breaking and leaving portions of spring between the plates, but it would cause a slipping clutch, not a hard clutch. I suppose a piece could have gotten into teh release mechanism or is jamming in a pressure plate spring. I can't think of anything else that would cause the clutch mechanism to jam part way through it's travel.
Anyone got any suggestions? The next step is a clutch cover gasket and having a look.
EDIT- Just found this, the star spring changed later on, just like the GTR's. It was a running change to eliminate star spring failures....
http://www.ronayers.com/fiche/400_0461/ ... rent=13460" target="_blank
Note spring 39130 is different.
**second edit** Star spring and new nut share same part numbers as later GTR application, I think we could have a winner....

Regards, Andrew.

Re: Clutch not disengaging - why?

Fri Dec 07, 2007 9:26 am

Like Andrew said, that's what's going on. Big thanks to him for the assistance in pulling stuff apart and bleeding stuff, I'm learning more and more every day.

The only thing I did was change the oil and filter before I went to Victoria, for Penrite HPR 10 Gas engine oil. Non friction modified and plenty of people have said on this board they use it in their bikes. If it were the fault of the oil that the plates fused how far would I ride for that to happen, the bike behaved itself all the way to Lakes Entrance, a couple of days tooling around down there and most of the way home before it started playing up.

Re: Clutch not disengaging - why?

Fri Dec 07, 2007 10:05 am

Here we go, I think we have the problem:
http://www.concours.org/forum/topic.asp?TOPIC_ID=37724
Some incredibly knowledgabele Kawasaki people on that forum.

Regards, Andrew.

Re: Clutch not disengaging - why?

Fri Dec 07, 2007 10:29 am

Wow. Looks like it's time to jump in the deep end and get to know a bike engine/gearbox/clutch from the inside.

Thanks Andrew. I will ride it tomorrow in the Toy Run and then sort out when I can get some time to pull it apart.

Cheers again for the assistance,

Tony.

Re: Clutch not disengaging - why?

Thu Dec 13, 2007 7:02 pm

So by the looks of it I just need the two springs, one nut and a gasket, anyone pulled the clutch cover off engines like this and know if I need to drain the oil or if I can leave it on the side stand and do it with the oil in? It's done bugger all km and I'd rather not change it if I can help it.

Re: Clutch not disengaging - why?

Thu Jan 03, 2008 9:59 am

The ZXR750L clutch diagram shows the changeover at 1993:

http://www.ronayers.com/fiche/400_0346/ ... clutch.bmp

I'll grab some bits and I think Gos is going to give me a hand with it one day soon, at least we'll be able to work on the process of elimination some more if that's not the issue.

Cheers.

Re: Clutch not disengaging - why?

Mon Jan 21, 2008 8:44 am

OK so the springs and stuff are all fine according to Dr. Gos and he said it's going rock hard because the slave cylinder is bottoming out against the casing that it sits in, it's like the pushrod and cap are too short and not getting to do anything. I know nothing fell out when we pulled it apart out at Typhoon's place, do things break off these bits ever?

http://www.ronayers.com/fiche/400_0222/ ... rent=13460

Part numbers 11012-1569 and 13116-1141 are the bits between the slave cylinder and the collar that the push rod pushes on.

Anyone ever had any clutch problems in this area?
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