my 400ex smokes when i give it gas from and idle it doesnt smoke anywhere else that i know of.... it only smokes for a sec then it will stop even if im still giving it gas then if i let it idle for about 10 sec and gas it again it will smoke its black smoke.... it only does this on a warm day like today 50 degrees + its about 60 here.... but its normally 30 or 40 this time of year and it doesnt smoke at all when its that cold any help??? thanx

 

Sounds like you are having the same trouble as I am...

 

any idea on how to start to cure it????

 

I think it is the jetting but I don't know exactly how to do it.

 

It sounds like a rich pilot issue that might be fixed simply turning the pilot screw. Don't quote me on this, but turning screw clockwise richens, counter-clock wise leans. If this is wrong someone please correct me. Black smoke is rich so if I'm right you would turn pilot screw counter clock wise to lean it out ridding you the black stuff off idle.

 

I have a 2000 400ex the problem is that the oil is sticking to the cylinder wall and when you start it the motor is blowing the oil of the wall
it shouldn't hurt it as long as you check the oil and keep the level in the correct range