Z900 A4 sticking clutch

[Gray17]

Hi Guys, yep me yet again this bike is really fighting back it just point blank refuses to give in!
Anyway for some reason when i got the bike it had the wrong clutch cable on it was far too long so had to re route it, but it worked ok, also when i had engine apart, i noticed someone had bodged the clutch basket, managed to get a good used one from forum member and fitted that, all plates and springs in good condition so were re fitted.
Anyway just lately especially when hot, you pull clutch fully in and it drags, its got correct engine oil in too.
So i removed old cable bought the correct one and fitted that thinking that would help, exactly the same, but worst as when hot its not smooth it almost sticks when releasing not smooth so bike jumps all the time, not good.
Any ideas please, didnt paticularly want to strip it, thought best ask 1st.
Thanks

[warren3200gt]

Did you dismantle, regrease and properly adjust the actuator arm assembly?
When everything gets hot and expands maybe it sticks.

[Gray17]

Thanks for reply, yes thought i did, followed info in workshop manual, but will re check it, that said im def loosing confidence on my ability to doing stuff on it, as it never seems to go to plan
I recall using a smear of copper slip on the pushrod and arm, and also checking it was straight by rolling it on piece of glass before assembly, but it may have altered now, made sure all the plates and driven plates were burr free also.
The original clutch basket had one of the spring mountings bodged with a screw on inside and araldite, hence replacement, if one of them has snapped again its possible its putting clutch out of true, although replacement was used it was in good order with no damage.
Will re check adjustment 1st if seems ok, will have to bite bullet and drain oil and re strip clutch again argh!
The number of jobs to do are mounting up, despite Robs initial adjustments.
Got camchain to replace, the dyna ignition as not genuine, The tank needs to be repainted due to previous fuel splashes lifting paint and now clutch issues, only done few hundred miles on it since full rebuild, was hoping to see month out before doing so but looks unlikely now.
If draining oil to inspect clutch may take oppertunity to do camchain at same time, whilst in bits makes sense to get tank done too.
I do enjoy riding the bike brings back nostalgia of my youth and when it runs well its great, but when not its a real PITA!

[warren3200gt]

Could also be due to the oil your using or it's level. As it heats it also thins.

[Gray17]

Well i asked Forum whats best oil for bike a while back 1 of recomendations was Mobil super semi synthetic 5-40w, which is what i used, think fully synthetic was frowned on and caused issues so hopefully not that.
Ive also found several other issues ( does it ever end)
First leak from cam.cover, no biggy but made a bit of a mess, but also
Tacho drive leaking seems o ring has split. So will replace that.
Also on way back from run yesterday bike was misfiring badly on 2 cylinders. What with that and clutch made riding it a real challenge!
Removed plugs cylinders 1 and 2 lovely chocolate colour, but plugs 3 and 4 black and sooty, now Rob put 4 brand new genuine NGK B8ES in as part of the sorting process, but it originally had B7ES which is hotter plug posdibly to prevent sooting up, but its all been set up correctly now by Rob, carbs ballanced, floats set so cant see that being the issue.
Im going to do compression check just in case but again its all new cant see that being issue.
Suggestions??

[warren3200gt]

That's far thinner than any oil I would use. The workshop manual I have says 10/40 for a 900 and even that is thinner than I use. The filler cap says 10/40-20/50 on both my 650s, can't recall on my 900.
Oil is a personal decision but one that makes a huge difference to gearbox/clutch feel.
The first number is how thin it is when cold. The second how thin it is when hot.
As your presumably only riding in fair weather 10/40 is more than thin enough for cold start.
The choice of mineral, semi and fully is also vitally important.
Both semi and fully have friction modifiers in them. Both can make the clutch slip unless they have been tested and approved for wet motorcycle clutches. If the have they will be JASO MA or
JASO MA2 approved and that will be printed on the container. If they haven't then DO NOT use them.
However, these bikes were designed and built in the 70's. Both oil technology and machining tolerances were not what they are now.
I like my oils to fill those tolerances and remain thicker when hot for the same reason.
I've used 20/50 mineral in my 70's bikes for 45 years and never had an oil related gearbox or clutch issue.
It should also be said that low oil level will make every gear change feel clunky.

[Gray17]

Yes you are correct Warren ive re checked typo error it is 10-40w not 5-40w. Never had problem.with clutch slip, its almost like it pulls in smoothly, although you do get a clunk when select 1st from Neutral, but goes in and out of gears easily and selects Neutral easy too, with clutch pulled in. Problem is you normally release lever tobiting point then add a few revs, release a bit more and off you go.
In my case you get to biting point release a bit more and it sticks by which time as its only firing on 3 intermittent dies, so you add more throttle it revs then clutch releases so it jumps. Def not good, wasnt doingvthat when collected from Robs it was perfect. Ran very smooth.
Its only since ive been using it this has happened, dont know if a setting has moved etc but reluctant to play around with settings for fear of going back to start again.
The only thing thats changed is the magnet dropped out of cam on Dyna, thats back in and seems to work fine, advance is spot on on both coils 1 and 4 and 2 and 3.
Beein in garage and done compression test
Cold throttle open i get
Cyl 1 165 psi
Cyl 2 163 psi
Cyl 3 160 psi
Cyl 4 165 psi
So all are good and almost the identical readings, thats with no oil squirted in bores either. Im guessing the problem.must lie elsewhere!

[kev edwards]

The firing on 3 could be down to just starting and stopping all the time and going nowhere, you end up with sooty plugs.
Regarding clutch, if your cable and actuator are working OK look at the clutch basket again,you may be getting a uneven disengagement, causes may be badly worn bearing or springs, or in the case of a lot of yamaha xs650's a warped pressure plate, I have had two of these, and a 350/4 i bought that had been recommissioned by a ho-da tech had the clutch put back together wrong causing the same type of issue.
Reading this thread the clutch basket pressure plate is the main thing I would look at.

[Gray17]

Thanks Kev, looks like I'm going to have to strip the clutch down to check, check all Plates again, spring lengths and basket. The new cable is brand new and runs smoothly as does the release arm and rod. Got to internal issue.
As for plugs its always cylinders 3 and 4 that soots plugs, 4 being the worst. Rob fitted brand new B8ES, however it originally had B7ES could re try them? All chokes seem to be shutting off correctly, whilst the slow running was an issue initially, since the repairs been great, but now after 200 miles its back again sooting the plugs whilst i
uderstand slow running uses pilot jet, mid range to full uses main jet, these have been set up by Rob, along with new needles, cant see how that can have altered, so if 1 and 2 are a nice chocolate brown, no oil in bores, how are 3 and 4 sooting up? Im once again at a loss.
These older machines are def a challenge thats for sure!

[kawasaki_man]

I have experienced a sticky clutch release and found that the clutch pushrod had some very small wear groves on it. I replaced it with a new pmc clutch pushrod and was stunned that the clutch release was now as smooth as new.
Very quick and easy to check the clutch pushrod condition. Any slight groves and I would fit a new one.

[Gray17]

Thanks thats something ill def check whilst its apart.
Looks like im building up quite a list of to do's
1. Check clutch assembly
2. Replace camchain
3. Send tank away for repaing ( thanks to Shell v power damage,)
4. Same time have right hand side cover re painted (yep it blew off at speed) without warning i hasten to add.
5. Check and/or replace Dyna S ignition.
6. Re fill original tacho dash pot with correct oil, new Tacho works up to 5k then bounces about.
7. Sort out soiting plugs on cylinders 3 and 4, biggest issue really as not something i can do.
On the plus side got till next april to get it sorted.

[Mally]

Lost my RHS side panel also , I drilled a hole in the fixing ( the pointed part that locates in the rubber grommet) and put an R clip into it to hold in place , the upper one that locates in the tool tray is easiest to do.

[gray]

I did that mod too Mally after losing a side panel many years ago. Prevents pilfering too when parked of an evening in city centres.
One thing to check that no one has mentioned yet is another area of friction as the clutch lever is moved out- the joint between the clutch lever bolt and its pivot hole in the clutch lever. If there is wear on the shank of the bolt, or if the hole is ovalled instead of round you'll get an irregular clutch release feeling.
Quick to check, at least. Remove the bolt , then the lever then fit one in the other and see how much slop you've got

[Gray17]

Thanks for replies Guys, both good suggestions. In my case the handlebar assemblies both sides are new as are the levers, probably pattern parts fitted before my ownership, but will check for wear on pivot bolt, think from memory its a shouldered bolt with lock nut.
Cant believe I've only done 300 miles or so since full strip and rebuild and already im having to re strip numerous bits apart again just to get it to be rideable. Def not what i imagined at all. The Suzuki GT750 i did a few years ago by comparison only stripped and rebuilt once and ran ok, although it did hunt slightly on overun but still rideable. Of course you dont get the plooms of smoke when opened up on tbe Kawasaki as its a 4 stroke, well you did but not now its rebored.

[DeadZedDave]

@Gray17
I think you'll find you start to upset a few people here if you start saying there's something fundamentally wrong with old Zeds.
Never in my long life of bikes and direct experience of Zeds - and I mean a lot of Zeds - have I ever known a person have so much trouble with Kawasakis finest.
In its day, the Zed was the fastest thing on the road - known to be bulletproof and unbreakable even with the most casual of maintenance by inexpert hands.
Tried and tested by countless riders globally.
The Z1 series bikes are legendary.
They made quite a few of them too....
Its hard to understand why you have such difficulties.
From what you've just written, you could perhaps try something which might suit you better:
https://www.thekettleclub.com/