what could make my 2000 400ex smoke?
i changed the oil and plug regularly and kept filtet clean(UNI)???
PLEASE REPLY BACK

 

It could be running rich. Have you increased the jetting size from stock? Is your plug black? It would help if you provided more information...

 

It has the stock jetting and i dont know if the plug is black. Poeple told me that i have a valve too tight ????
Holeshot2000@hotmail.com

 

Is it blue smoke? My 400ex puffs out blue smoke, but I was told to use Mobil1 15-50 synthetic to cure the problem.I don't know if it works because I cant drive anywhere because up here in nova scotia, canada, we have 3-5 feet of snow on the ground(seriously) And we are suppost to get 20-30 more cm of the stuff tonight. Oh well, no school on the 6th!!!!!!!!! anyway, if the smoke is blue, it is likely engine wear(piston, rings) and if it is black, it is likly running too rich on fuel.

 

Its white and it doesnt smoke when it idels only on the throttle!!!