400ex jumping the timing after fresh rebuild?

[atvjunky57]

i just bored 2 a 416 with 11-1 comp n put a hot cams stage 1 cam, new cam gear, n i got a head from a 04 with the 04 vavles, cam chain n cam chain tensoner n it jumps the timing. c i rebiyuld it n it jumped when we stared it and we took it apaprt n put new gears and chain n tesoner but that only helped it for a day then i went to start it n it did it again does any body know wats up? all the parts r new. i also have a yoshi pipe, but dont know if its jetted it ran fine when i rode it just didnt idle?

[jasonwayne222]

the only way is if there is too much slack in your chain or you got a gear tooth broken off or badly worn. tighten up your tension to were you have no slack at all, if it still does it then i would look in the bottom end gear. I take it the cam gear is good since you have looked at it several times

[atvjunky57]

well i put a new one in is the thing bc my other one was worn so bad.

[coreo5]

if the cam chain is new and the cam gear is good...then the probably the gear on the crank