Help KX125 Clutch

[LittleJohn]

Help please, I have just rebuilt the bottom end of my 1999 kx125 and now the clutch is not engaging. It has a new clutch hub, I got rid of the grooves on the clutch basket and de-glazed the clutch plates but it still doesn't work.

I have been tightening the clutch nut with a torgue wrench to the specified Nm but as I don't have a clutch holder I have to use a socket on the drive shaft tied to the frame...... so may not be to the correct toruge setting. The clutch hub does move freely in the clutch basket with no plates in there.

Also measured the springs and they seem to be longer (by about 1 - 1.5mm) than that specified in the service maunal. Not sure if this could cause the problem.

Upon fully tightening the pressure plate (to appropriate Nm) the clutch doesn't engage, but it seems like all of the plates are sticking together a bit. Have even put everything back together and run the bike for a few minutes, then tried the clutch and nothing, the back wheel just spins, no matter what gear. If you put the back brake on the bike will just stall.

Any thoughts on what it is????? Please help, sick of pulling it to bits and putting it back together just to find out there has been no change.

[cheese]

There is a rod that pushes teh hub out to let the plates seperate, Id say this could be worn? I've only pulled appart a RM250 one so I'm not too sure about the KX.

If you pull teh clutch in does it push the part holding teh plates out?

Longer springs - should be ok, just stiffer clutch.

[LittleJohn]

Yeah it pushes the pressure plate out a few mm's, looks like a big enough gap but maybe will measure it and see if I can find some specs for it.

Thats what I thought about the longer springs......

[barty5]

Yeah it pushes the pressure plate out a few mm's, looks like a big enough gap but maybe will measure it and see if I can find some specs for it.

Thats what I thought about the longer springs......

did you oil the plates as you put them back in the basket??
the springs will shrink as they weakin with age.

[theblacksmith]

Have to agree with Barty - oil them with the most slippery shit you can find. Try loosening the bolts just to get them slipping and then re-tighten.Take up any free play so you can get max travel on p/plate.Keep us posted.

[LittleJohn]

I oiled all of the plates when installing them, using Bel Ray gear saver oil, supposable good stuff. Have just restripped everything, going to deglaze again, then put everything back together in the hope that it works. Talked to my mechanic and he reckons the clutch nut is to tight so will try it a bit looser and see. Theanks for the tips, better get back out to the garage and see if anything will work.

[LittleJohn]

stripped down again, deglazed, soaked in oil, put back in, all parts there according to the diagram on kawasaki website still didn't work. Adjusted clutch nut starting from finger tight thru to as tight as air gun would get it, trying clutch at different tighnesses & pressure plate tighnesses still nothing. Have noticed pressure plate moves out but the plates seem to be stuck together. Not sure if this bel-ray oil is the problem but its in the manual as transmission oil to use

Now at a loss. Heading away nxt wk for a few weeks so maybe bike will have to wait to go to mechanic when I get back.

Still open for ideas in the meantime so I can fix it.

[4stroke]

i assume therod is moving through the centre of the clutch, does the clutch lever feel like it has weight on it, like it used to before you dissasembled?
im unsure on the kwakas, but the hondas have a needle face roller bearing that gets pushed by the push rod which pushes the clutch cover out-ward.

[LittleJohn]

Yeah the Kawasaki has a bearing at the end of the push rod attached to the pressure plate which is all there. Clutch lever has no slack in it & plenty of pressure behind it. Pressure plate moves in & out fine with enough gap out when clutch lever is pulled in

[4stroke]

hmmmm, the plates arent tight on the outside of the clutch basket, arround the circumfrance of the plate? did you put new steel plates in with the fibre plates?

[LittleJohn]

Only new part of the clutch was the clutch hub. Clutch basket has been degrooved (grooves from friction plates) plenty of room for friction & steel plates. The pressure plate engages onto the friction plates nicely when clutch is out & obviously comes off the plates when clutch lever pulled in

[barty5]

Only new part of the clutch was the clutch hub. Clutch basket has been degrooved (grooves from friction plates) plenty of room for friction & steel plates. The pressure plate engages onto the friction plates nicely when clutch is out & obviously comes off the plates when clutch lever pulled in

you got the plates in the right order fiber 1st then steel etc etc should finish with fiber as well?
also looking at parts diagram there is a washer between the housing and the hub the plates sit on.

[LittleJohn]

Yip all plates in right order & the washer is there.

[cheese]

Maybe one of the steel plates is warped?

[LittleJohn]

Yeah i'm thinking that one mite be warped or its the oil I'm using. Can't think or find anything else that it could be.

[cheese]

have you got a steel ruler? use the side of it to see if they are all not bent. To be honnest there is not much else I could think of that would cause the problems...

Where in Auckland are you?

[LittleJohn]

Hadn't thought of using steel ruler so will check tonight if any are warped.
I'm on the Shore near Hauraki Corner.

Just found out this arvo a stupid truck driver has taken down our phone line today which can't be fixed til tomorrow so will have no internet tonight

[4stroke]

does the hub look the same as the old one, obviously you changed it as it was worn or brocken but it could be machined wrong, or posibly the wrong part.

[theblacksmith]

What a mind boggler! Makes me wanna come up and investigate- curiosity killed the clutch!

[4stroke]

What a mind boggler! Makes me wanna come up and investigate- curiosity killed the clutch!

yeah i was thinking that before.

[cheese]

Should we all head over for a beer and ponder over it?

[Buddy L]

ill be their, maybe only good for a laugh and to help drink.

[vr4king]

Hmm does it cycle through the gears ok and can you find netural?.............Im thinking theres some cog on cog action that shouldn't be happening

Hows the kickstart feeling?
Can you hit netural with the clutch cover off and crank it over using the crank end without the back wheel turning or vise versa spin the wheel and see if it rotates the engine?
It really must be something else if the clutch lever is lifting the centre hub or you got to many plates in there but that seems impossible unless the new centre is different

Please inform us when you do find the culprit cause now im curious

[4stroke]

im picking that its gota be something thats been changed, if hes only changed the clutch hub, there must be a descepancy in the hub or an assembely error.

[LittleJohn]

Thanks guys for all the replies. Finished work late yesterday & couldn't be arsed pulling it to bits yet again. so am thinking i will tonight. hopefully our internet will be back on by tonight & i will get back on & do some replies.

[LittleJohn]

does the hub look the same as the old one, obviously you changed it as it was worn or brocken but it could be machined wrong, or posibly the wrong part.

Compared the new one with the old one, both exactly the same. Also it is a geniune Kawasaki hub.

[barty5]

If You Want Feel Free To Bring It In To Work Shop It In Newmarket Happy To Help Out Have A Look One Evening Lots A Beer In Fridge Sure If The Cheese And The Rest Come Down We Could Figure It Out Im Here Late Most Night Got Home Last Night Just After 12 (moral To That Is Dont Do Engine Transplants On Vectras)

[LittleJohn]

Hmm does it cycle through the gears ok and can you find netural?.............Im thinking theres some cog on cog action that shouldn't be happening

Hows the kickstart feeling?
Can you hit netural with the clutch cover off and crank it over using the crank end without the back wheel turning or vise versa spin the wheel and see if it rotates the engine?
It really must be something else if the clutch lever is lifting the centre hub or you got to many plates in there but that seems impossible unless the new centre is different

Please inform us when you do find the culprit cause now im curious

It goes through all of the gears no problem (apart from obviously no clutch working), can get into netural, bike starts sweet as in neutral, can then put into gear, go through them but when pull clutch in the wheel keeps spinning. Cannot use kickstart when bike is in gear but when it is in neutral, no problems. Bike free-wheels nicely in Neutral as well.

If I have the cover off and wheel the bike forwards the, pull the clutch in and put it in gear it is very difficult to keep going forwards and will slowly turn the engine over. The plates don't split what so-ever, but if you put your finger in and manually do it they move. Seems like they are stuck together a bit!!!!

As far as the clutch goes only the hub was changed. The bottom end has had a new crank, bearings and seals.

[LittleJohn]

If You Want Feel Free To Bring It In To Work Shop It In Newmarket Happy To Help Out Have A Look One Evening Lots A Beer In Fridge Sure If The Cheese And The Rest Come Down We Could Figure It Out Im Here Late Most Night Got Home Last Night Just After 12 (moral To That Is Dont Do Engine Transplants On Vectras)

Cheers, am heading away on Monday for 3 weeks, if I don't get it in the weekend I might have to take you up on that offer......

[LittleJohn]

Just come in from the garage for some dinner, missus made me, I have re-stripped the clutch (and all parts were there and in the right order), cleaned and dried everything. Have checked for warpage and thicknesses of both clutch plates and friction pates. All are good and within service limits.

The friction plates have clearance inside the housing and can freely move within it. There is no damage to the friction plate tangs or to the clutch plate teeth.

Am still at a loss. And now the clutch cover gasket is stuffed!!!!!!!

[scott411]

after reading this thread i think it is more a actuation issue than a clutch plate issue, if they are all with in spec then they should come apart which seems to be the problem you are having

jsut my thoughts,

[LittleJohn]

Thats what I'm thinking. Maybe I will try some different oil, but thought the Bel-Ray gear saver two-stroke transmission oil was really good.

What sort of oil do you guys use??

[4stroke]

yeah i was thinking the same scott, the oil shouldnt bother it to start with, well to make it work any-way, i use motoul 5100, the pressure plate move's in and out when freely when the clutch is lever is depressed, also without the clutch cover on does the rest of the clutch cable and mechanisum move freely?

[scott411]

oil will not make a difference like this,
sounds like the clutch is not unlocking, so it is not activating enough

[Katman]

Sorry if you've answered it already, but just double checking - do you have the washer in behind the clutch basket as well as the washer that goes between the clutch basket and clutch hub? In other words, the two needle roller bearings that the basket spins on should have a washer front and rear.

[LittleJohn]

All parts are here and were together as per the diagrams on the kawasaki website and my manual.

I was just packing up for the night and put everything back together (negetive the clutch cover) as per. I didn't put any oil on any parts (apart from inside the sleeve and on the needle bearings) and after tigthening everything up I gave the back wheel a spin, put it in gear and it obviously stopped. I then pulled the clutch in and gave the wheel a spin, the clutch plates all came apart and the wheel spun freely, tried a few more times and same effect works perfectly.

Therefore as it is working with the plates dry I'm thinking the oil is making the plates stick together.... Tomorrow I will try some Motul oil (what my mechanic uses and was going to until lovely salesamn talked me into the bel-ray) and see if it works. Have to take the missus out for dinner as it is her b'day but will try and do it all before I have to go. Will let you all know if it works.

[scott411]

i ran belray gear saver oil in kx85s and 125;s for over 10 years,
2 stroke gearbox oil is not particuly complex,
beleive me, that is not the problem,
couple of things to check,
are the bearings that the clutch actuator arms run on, they are known to fail, this could be why it works when its on its side, the seal would have to replaced as well,

[LittleJohn]

Then still unsure. Have to get some more oil anyway as don't have enough to full transmission. Maybe something is a bit different since it's 5th clean and installation. Suppose will find out tomorrow when I get some oil and oil all the parts.

[LittleJohn]

yeah i was thinking the same scott, the oil shouldnt bother it to start with, well to make it work any-way, i use motoul 5100, the pressure plate move's in and out when freely when the clutch is lever is depressed, also without the clutch cover on does the rest of the clutch cable and mechanisum move freely?

Clutch cable and mechanism works fine. The pressure plate moves out and leaves plenty of room for the plates to split. The plates themselve didn't even move when it was all oiled up, there was just a big gap between the ends of the plates and the pressure plate.

[scott411]

are you doing this test while the engine is running? as the plates will not come apart until the rotaional force pushs them out

[LittleJohn]

i ran belray gear saver oil in kx85s and 125;s for over 10 years,
2 stroke gearbox oil is not particuly complex,
beleive me, that is not the problem,
couple of things to check,
are the bearings that the clutch actuator arms run on, they are known to fail, this could be why it works when its on its side, the seal would have to replaced as well,


Bike is standing up-right (not sure if that is what you meant) but the clutch release lever (think thats what you mean) seems to work fine. With no clutch in it rotates freely, and with clutch in the pushrod is working fine.

[LittleJohn]

are you doing this test while the engine is running? as the plates will not come apart until the rotaional force pushs them out

Originally was doing it with engine running, but tonight haven't done this. Shouldn't the clutch still work without engine running, i.e. if it is in gear and clutch is in I should be able to start the bike without it moving forward and should also be able to walk the bike forward???

[scott411]

normlly on older dirtbikes the clutch will stick the first time you put it into gear, meaning it will stall or lurch forward, the degroving of the cltuch basket should have fixed this tho,
when you kick it over it is harder to start the bike in gear as there is still some drag on the clutch untill the bike is kicked over the the plates forced out buy the spinning basket,
the only think i can think of is the basket is not right not allowing the paltes to slide freely away form each other, but you have checked this i am unsure what it could be,

[LittleJohn]

normlly on older dirtbikes the clutch will stick the first time you put it into gear, meaning it will stall or lurch forward, the degroving of the cltuch basket should have fixed this tho,
when you kick it over it is harder to start the bike in gear as there is still some drag on the clutch untill the bike is kicked over the the plates forced out buy the spinning basket,
the only think i can think of is the basket is not right not allowing the paltes to slide freely away form each other, but you have checked this i am unsure what it could be,

You cannot kickstart it with it in gear at all. If I start the bike up, leave it to run for a couple of minutes, then put it in gear it goes in like there is no clutch (this is while bike is on stand with back wheel of the ground). Can go through the gears (still no clutch) and then if I pull clutch in and put the back brake on the bike will just stall )or work the engine if brake not fully on)

The plates can slide freely in the basket and have some room between the plate tangs and the housing fingers.

[vr4king]

I know on the kwakas the "cam" part the one that turns and pushes the rod that runs tthrough the cases not sure on the technical term,but anyways they can cause probs as they wear out like having a "on/of" clutch effect maybe yours has worn enough to not get enough purchase on the rod and drive it forward to release the plates with the centrifugal forces opposing it when the engines running

Oh if the bearings around this part have gone it will cause this too and they are a real pain to remove trust me i know lol

[LittleJohn]

Thanks for all the help and suggestions from anyone. All I know is it now works. I changed the oil to Motul Gearsaver after it worked when it was dry, then put everything back this arvo. After putting it together while it was still off the ground I started it and when I put it in gear the back wheel spun away, but as I put the rear brake on it instead of stalling like it did last time the clutch plates came apart and the wheel stopped spinning.

When I first started it, once it was on the ground in the backyard (nieghbours love it when I do this), I could kickstart it in gear with clutch in but it did drag a bit. Started up in nuetral then went to put it in gear and it just stalled, tried again and the plates again came apart and away I wnet. Went up through a few gears and back down, now it is working perfectly.

If only it had done this a few weeks ago, could have gone for a ride before I headed away. Now will have to wait until I get back in July.

Only thing I changed throughout trying everything was the oil!!!!!!:argh:

[theblacksmith]

Glad to hear you fixed it. Happy riding when you get out there