anybody got an idea

[sproket186]

I have 02 400ex with a 426 kit,It has a knocking sound in it, I think its the lower end but not for sure, anybody got any ideas,anybody else had any issue like this before.

Just seening if anybody has any ideas before i pull it out of the quad and go threw it.

thanks

[headache]

you might as well take the topend off the motor and check it out. You'll know whats wrong when you find it.. Could it be the valves or something like that?

[woodsracer144]

when does it knock? is it like a ticking sound that ticks faster as it revs? its most likely your valves out of adjustment... but it also could be piston slap... in that case you need a bore job... how much time is on the motor?