Seem to have a problem with oil coming out of the filler hole in the tank where you check the level. Took bike (2006 KFX 400) to shop to have the clutch cover replaced got it home changed the regular antifreeze over to EVANS WATERLESS COOLANT warmed it up but would not idle, kept stalling. Checked the oil and it shot out the filler hole and lots of it. Took it back to the shop they said maybe vapor lock. Don't know what that has to do with the oil? Went back 2 days later, they said they over filled bike. Got it home. Next day took it off truck still would not idle properly, checked oil again and it's coming out the filler hole again. Could there maybe be something plugged? Oil filter, line? Any suggestions would be great. This problem did not start until we got it home from the shop and changed the anti freeze.

 

<div class="FTQUOTE"><begin quote>Originally posted by: gogreen

Seem to have a problem with oil coming out of the filler hole in the tank where you check the level. Took bike (2006 KFX 400) to shop to have the clutch cover replaced got it home changed the regular antifreeze over to EVANS WATERLESS COOLANT warmed it up but would not idle, kept stalling. Checked the oil and it shot out the filler hole and lots of it. Took it back to the shop they said maybe vapor lock. Don't know what that has to do with the oil? Went back 2 days later, they said they over filled bike. Got it home. Next day took it off truck still would not idle properly, checked oil again and it's coming out the filler hole again. Could there maybe be something plugged? Oil filter, line? Any suggestions would be great. This problem did not start until we got it home from the shop and changed the anti freeze.</end quote></div>

I work on & repair cars and not bikes, but if your gaining oil but not adding any, you might have a blown head gasket or oil is overfull.

Never seen oil "vapor lock", coolant yes, but not oil.

 

Drained oil and got about 500ml of extra oil. I think I fix that problem. Did not spit out oil after running for about ten minutes. Had to make a new post about the cooling sysem though. Appreciate your input.

 

If coolant was getting into the oil it turns a light grey color that you couldn't miss when draining it.

 

I suspect you may have a crankcase vent problem. Some fumes blow past the rings on normal operation, and if not properly vented it will build lots of pressure.