Noobie needs help! 400ex smoking

[HondaHustler]

Okay heres the deal. i have a 2007 400ex it loves to smoke. esp when cold. ive been told its the valve seals but personaly i think its rings. its definitely blueish smoke so its burning oil


i needs your expert advice guys.

thanks alot, HH

[paganmac_10]

Just my .02 but, either way the head has to come off so might as well do the vavle seals and put some new rings in it and hone the cylinder if its not messed up......

mac

[timmy400exfast]

whats all done to it if its bored it could possibly be alittle bit off and there could be some blow by or it could be the seals or rings just my .02 lol

[rocky_mtn_honda]

Originally posted by paganmac_10
Just my .02 but, either way the head has to come off so might as well do the vavle seals and put some new rings in it and hone the cylinder if its not messed up......

mac

x2...also i have a set of oem valve seals extra that i didnt need because i got some in my gasket kit....$25 shipped anywhere in the US for all 4

[HondaHustler]

Originally posted by timmy400exfast
whats all done to it if its bored it could possibly be alittle bit off and there could be some blow by or it could be the seals or rings just my .02 lol



the motor is 100% stock

[VTredneckgames]

when does it smoke?

at startup and at WOT, then it is the valve seals. If it smokes all the time even when warm, then you definately need rings.

[matts27]

Try some Lucas oil treatment if you wanna keep riding. My quad was smoking real bad and it cleared it up, went from burning a quarter quart almost to nothing. It's an 02 and ready for a rebuild but wanna at least finish the year. Good luck