Figure this one out

[paul331]

Here is the issue
A friend has a yz250 2002 .
he has replaced all these parts to OEM
clutch cable
clutch basket
clutch fibers
clutch plates
clutch bearing
clutch push rod [ i think its called that ]
and clutch springs

he rides and after 1/2 hr or so the clutch play goes away and tightens to the point of clutch slipping .

he has tried all types of oil with no luck
and all clutch parts are new OEM

i have no idea what it can be
any help
thanks

[paul331]

no one ??????

[wadschopshop125]

what are the clutch springs trouqed at?

[paul331]

to spec.

[Sledder]

I'd switch it to barnett springs and run only 10w 40 regular motorcycle oil

run a little more slack in the cable too. and I bet the problem will go away. If it doesn't go to the carbon fiber barnetts kit and they will not overheat as quickly,...but you should be able to get by fine with the stock plates if he didnt already glaze them too much,you may want to have a look when it is apart and make sure it isnt blackened up.

Sometimes on those long pro motos you see those guys always hitting their quick adjust lever roller to slack off the cable as the clutch heats up if they are running stock plates(thats why many of them run aftermarket perches with the clutch "quick adjust". Barnett carbon fibers on those models that are sensitive is better,...but the springs help a lot so that it doesn't slip in the first place.

[paul331]

he has ran a couple different oils with no help
clutch play is adjusted before he rides ,he never had this issue before
the clutch play goes away as he rides , he does not ride any different than he did before .
its odd !!
he can put to much play in the clutch and it still goes away after about a 1/2 hr of riding .
and tightens to the point of clutch slipping .
as i said he hs replace everything with oem .
this is a weird one !!!

[Sledder]

Tried all kinds of oils?..he may have had a synthetic or thick gear oil in there and slipped it once and now it is glazed. Maybe it had a short or soft set of springs orsomething.The thing is is it is a mechanical device,it is just a clutch..the only thing to cause it to heat and fade like that is slippage./..and maybe now it is glazed ..if so it is done.

At least put a new set of fibers and some stronger springs and get some regular 10/40 mineral motorcycle oil in there and try it out,he needs them anyway.

I know you will hear lots of hocus pocus about"I ran this or that oil and never had trouble"....but facts are facts and the least slippage occurs with non synthetic regular motorcycle oil period. Been there,proven it and done that.

...just look at the honda 250F four stroke,...the only 4 stroke with separate oil,.....they tell you to run synthetic in the engine comp. ,..and to ONLY run regular (non syn )in the tranny to prevent chances of slippage...these are the only thumpers that have the separate oils and they specify it clearly.

Some guys are harder on clutches than others,in this case the guy probably just slipped it hard once and smoked it up in there a bit and now they need tossed. it happens sometimes.

Just my experience,hope it helps. I hate when you get something weird like that. Best of luck!

PS,make sure he soaks the fibers in oil for a while first and does a pretty easy 15 min ride on them first time out.

[warticus]

I had this problem on my 1998 kx250. Replaced plates, springs, basket, cable. Nothing happened till i replaced the arm which links the cable to the engine and used a cheaper grade putoline oil instead of the expensive synthetic one. Works like a dream now, but dont know which one solved it!
Hope its of some help

[nd4speed]

Try to run ATF Type F that allows the most clutch grab of anything I have run.