Clutch drag on 82 KZ750-R1 (GPz)

I just adjusted my '82 KZ750-H3 using the same method after I replaced my friction plates and bead blasted my steel plates. Now I have to hold on tight when I twist the throttle hard....No more slipping!

Exactly the reverse situation for me i want the clutch to disconnect but for some reason it always drag (even in the worse case scenario the gears _should_ stop spinning by themselves when you hold the clutch but not! )

Let just pray that adjusting the clutch release system (or pushrod) will do more than modifying the clutch cable play.

It's like now i have the correct play around 2mm at the handle but when i pull it at max i feel that the clutch move 15/16 of it's normal travel. 1/16 is not enough drag force to stall the engine nor push the wheel forward but enough to keep gears spinning with clutch disengaged when it's in _neutral_. This is the cause (from my POV and logically) the big clunk and gears grinding when trying to switch from neutral to first gear!

Btw, even with no play (not recommended) it's the same thing except clutch start slipping when riding. It just wont disconnect damn it!

Hope this help more!

Anyway i will try both Patton and OMR advice tommorow!

Thanks!

ELCouz wrote:

...i want the clutch to disconnect but for some reason it always drag (even in the worse case scenario the gears _should_ stop spinning by themselves when you hold the clutch but not!...even with no play (not recommended) it's the same thing except clutch start slipping when riding. It just wont disconnect....

With bike on the centerstand, engine idling in neutral with rear tire slightly off the ground, the rear wheel will gently rotate forward as if in gear. This phenomenon is perfectly normal, and movement of the rear wheel is easily halted by hand pressure against the tire. And this movement occurs regardless of whether the clutch lever is being squeezed or not squeezed.

When sitting astride the bike on level pavement, idling in neutral with or without the clutch lever being squeezed, such as while stopped for a traffic light, there should be no tendency for the bike to pull forward.

Likewise, when sitting astride the bike on level pavement, idling in first gear with the clutch lever being squeezed against the hand grip, such as while stopped for a traffic light, there should be no noticeable tendency for the bike to pull forward (unless the clutch cable snaps, which will cause the bike to lurch forward).

Perhaps the existing clutch cable is frayed under the sheath and stretching, so as to prevent full pulling motion when the lever is squeezed against the handlebar grip.

Or maybe the supposedly round hole through the lever has wallowed out, or the shouldered screw is badly worn, so as to inhibit normal lever action.

Good Fortune!

I had a very similar problem on my GS1100. Banging into first gear and VERY rough shifting (esp at low speeds). Drove me nuts for LONG time but finally figured it out. Try the following:

1: Open the clutch cover and remove the metal and fiber plates. Check ALL of them for flatness. Replace as needed

2: While the plates are out, check the condition of the clutch basket and clutch hub where the fingers of the plates bear against the aluminum. Feel back and forth along each recess. They should be smooth. Feel for grooves where the clutch plates have embedded into the aluminum. These grooves will trap the fingers of the plates and not allow the plates to separate when the clutch lever is pulled in and the clutch will drag.

I was able to smooth these areas with a file. Reassembled and the clutch worked like new again. Easy shifting with no clunking into gear.

With bike on the centerstand, engine idling in neutral with rear tire slightly off the ground, the rear wheel will gently rotate forward as if in gear. This phenomenon is perfectly normal, and movement of the rear wheel is easily halted by hand pressure against the tire. And this movement occurs regardless of whether the clutch lever is being squeezed or not squeezed.

I would like to test this but this is dangerous doing this alone (need to jack the bike) because i have no centerstand (4 into 1 is in its way). I'll try this weed-end with a friend.

Also, even with a 45 min long test ride the shifting behave the same as when cold

Bad news OMR, I've adjusted the clutch release system ... it's the same thing.

Sadly, I think the only thing left is to have a look inside this baby.

Best Regards,
Laurent

"Bad news OMR, I've adjusted the clutch release system ... it's the same thing."...

Wait one... In my OEM service manual, it states loosen cables, then the nut, back the screw out ok... Then it states turn in till hard then back out 1/2 turn... ok... then adjust cables.

In following the manual guess what... just as your describing... Hmmm... Mind you I have all new clutch plates and springs but still WTF... :S

So on the phone with Mi Amigo Mentor and friend Plummen, he replies to try this..

Follow the spec but instead of turning the screw in till hard against the release mechanism/push rod then back out 1/2 turn...

Turn in the screw just till you feel it touch!
Then back it out 1/8 to 1/4 turn... Then adjust cables as specified... Guess what.. Problem all gone!


You may want to give this a try pre-disassembling your engine.... Have nothing to loose at this point...

Keep at it, you'll figure it out...

OMR

No improvement here OMR,

I will take a look to the plates and pushrod to see if everything is okay.


Btw, how do you remove a stubborn clutch cover. I've tried gentle hit with a rubber hammer. I'm out of luck, still wont get off from the engine. Does it have guides pins?

Regards,
Laurent

ELCouz wrote : "I've read on a forum that people put a mix ATF oil with their engine oil to eliminate the clunk and sticky clutch problem."

DON'T DO THIS! Your bike was designed so the clutch will operate smoothly with motor oil in the crankcase. Monkeying with the oil will only trigger other problems (remember the oil lubes the engine and tranny, not just the clutch).

Bottom line: if the clutch is not operating properly using the factory recommended lubricant there is a problem with the clutch - not the lubricant. I would urge you to get a Kawasaki factory service manual for your model/year bike - they're nearly always available on eBay. Using the manual, adjust the clutch properly - there is a sequence to this process. If the clutch still slips or if the tranny doesn't shift smoothly it may be time for new clutch plates. This is no big deal, but you will need the manual to guide you through the job.

Simply put; you need to identify and correct the problem and not try to cover up the symptom. Let us know if you have trouble finding a manual. Some of us are pretty skilled at tracking them down. Good luck. Ed

Thanks for your reply i have now received the original service manual for kz750.

Btw, got the clutch cover finally by prying with a broom stick.

I have some warpage at 2 steel plates (out of service limits).

I think this can cause problems.

I will check if z1enterprise carry steel plates.


Thanks!

650ed wrote:

if the clutch is not operating properly using the factory recommended lubricant there is a problem with the clutch - not the lubricant.

Agreed


ELCouz wrote:

I have some warpage at 2 steel plates (out of service limits).

I think this can cause problems.

This will definitely cause clutch drag that no amount of adjusting will fix. Plates must be flat.

How's the condition of the clutch basket and hub where the tabs of the clutch plate bear against the aluminum?

How's the condition of the clutch basket and hub where the tabs of the clutch plate bear against the aluminum?

Very good condition ... just a little bit of wear marks (no dent)

Okay the problem have greatly improved (mostly disappear)...
Changed oil again for 10W40 JASO-MA compliant dino oil (was 20W50 and not JASO-MA approved (claimed to be motorcycle oil jeez!)... idle is smoother and clutch stick waaaaaay less than before.

Outside temperature at this time of the year is between 40F and 55F

With a brand new clutch cable on its way that would maybe solve the problem entirely.

With the 20W50 if i put the bike in the first gear press the clutch then crank the engine it would go forward! Now it doesn't do that anymore. Clutch was soo sticky that with first gear engaged clutch lever pressed engine turn off and i can't move. Now it's okay.

Is it normal that my clutch platters have a tendency to stick engaged even with a manufacturer recommended grade oil of 20w50 ? Kawa recommended 10W40,10W50,20W40 and 20W50.

You have to make sure the side cover mechanism is adjusted properly then go from there. You should have enough freeplay at the lever to stick a nickel in between the lever and the perch. Was this bike sitting before you got it? if so you may have to disassemble the clutch and seperate the plates. I had one stick on my DB that had been sitting for awhile took it apart and put it back together worked fine. and yes if you can lean the bike over enough to remove the clutch cover and not lose much oil. Damn I was late on the ball here or what.

I'm sure the 20W50 recommendation was for very hot climates. 10W40 is normal. Ed