clutch issues

[chevy383cid]

I've have a really nice 02 kx 250 thats tits,Theres only one problem,when The engine is warm and i'm costing ,I can pull the clutch in and the motor will not come down to idle( as if i never pulled it it) The bike starts good in gear,but i can still tell that the clutch is still ingauged. I've double checked,cable,pull rod,all the most common things,Whats funny about this is I've got a 98 yz125 that does the same thing,and i've replaced everything thing to do with the clutch(basket,pressure plate ,bearings pull rod, cable,plates) I'm running belray motorcycle gear oil ,I think it's 75-85 weight,I'ts for 2 stroke gear boxes,And in my yz I've tried all kinds of oil and had no luck,any help would be greatly appreciated!!

 

[Woodsquest]

I have the 02 KX250 as well. Next time you try coasting, pull clutch in and the motor won't drop to idle; hit the rear brake and lock it up quickly, then release. Will the motor drop to idle then and stay there while still coasting? Probably not.
I suspect that since it is occuring on both bikes that your oil is the culpert. What oil are you using and how often do you change it?
I use Mobil 1 15-50 and run a full quart and the bike coasts fine with the engine dropping to idle every time. Good LUck!