400ex smoking

[mad4106]

Hey guys i just changed my topend on my 400ex and it is smoking. I checked the oil level and it is too high could this be why it is smoking?!

[killer454]

to much oil could be the cause i guess,drain some oil out and see if it gos away.their is a drain plug at the bottom of the resovour.
i have overfilled mine before and it did not smoke.

if you just put a new top end in and it has smoked on first startup,you may have not lined the ring end gaps up right in the cylinder.

i know when i did mine a few months ago getting the cylinder to slide over the piston and keep the ring endgaps where they was suppose to be was a little tricky,but it worked perfect i have around 55 hours on it now with no problems at all.

just asking but did you have the cylinder bored out or just hone it for the new piston and rings?

[mad4106]

thanks! yea i had it honed for the new rings. another question im getting beat by a stock 400ex with just a slip on lol! i have modifications such as a full curtis sparks exhaust wiseco 11:1 piston standard bore though and stage 2 hotcam with stock carbereator. U think i need to have the stock carbeautor jetted again i bought it use so i dont know if it is or not and i also had the airbox on too?!

[RATPACK Z400]

If you didn,t jet it do that first and dont ride it untill you have done this unless you want to burn up motor! You should be able to beat him in drag with those mods but then again he could be better at it,switch quads then see if he wins !

[CJM]

1. if it profusely smokes all the time your rings arent sealing right and you must redo them.

2. if it just smokes at start up but goes away the valve seals need to be replaced.

[mad4106]

i just let oil out of the oil reservoir the oil was very black i just added new oil but it was between the middle this time and not overfilled it stopped smoking but i will let all of the oil drain from the bottom of the motor when i change it next time so im assuming it could be cause of the condition of the oil too