not starting

[Emp11]

hey guys i just rebuilt my quad and i did the cam mod. when i went to start it it turns over and over with a occasional backfire. i was thinking timing but i 80% sure i did that right but i never did anything with the shims or checked valve clearance. do i have to change them for the mod? i searched on here and never found the new clearance any help would be amazing!

[DS19]

Clearance is supost to be what it was stock Im pretty sure.

[ds450xracer]

I'm pretty sure the new cam will change your clearances, you will most likely have to adjust the valves.

[Quadrider43]

The lift on both cams is the same, which means your clearances should be the same as stock. You should definitely get in there and check your clearances. Mine were barely in spec, and I ended up adjusting them before I bothered buttoning up the top end. Something that I also ran into when I rebuilt my engine was that the timing mark was not setting the piston to top dead. If I had gone by the timing mark, the cams would have been way advanced. You may want to put a dial indicator on the piston to ensure that it is at TDC and check your cam alignment again.

[hcomras]

Did u remove the auto decompression pin?

[CANAMracerdad]

X2 what hc romas said ,
and yes you most likely will HAVE to readjust the valve clearance

[Emp11]

im pretty sure i did its the thing on the end of the cam that you can push in and stuff right? and how do you adjust the valves? just get different sized shims?

[bad moose]

Here you go. Should be all the info you need.

[Emp11]

thanks so much!! i hope i can get it running were going on a riding trip next week!

[Emp11]

i know were supposed to use 9.48 shims but what height should i order to get the proper adjustment.