400EX problem

[RedRider55]

ok my 416 just went through a grueling weekend on the trails and ran great. but near the end, i started to hear a rattling sound coming from the top of the cylinder head, but it still ran great. we had a 3 hour drive home and when we got it back home and took it for a little ride, it was puffin blue smoke. is this normal after a cold 3 hour drive? any suggestions?

[400ex28]

I would think you need new rings....

[mojoe2878]

check the valve clearance. you may have a leaking valve seal letting oil into the cylinder too.

[RedRider55]

i thought it was the rings too but my dad but never listins to me so i might just have to take it apart myself. i'll check the valves too while i'm at it