09 yz450f wont start after rebuild

hey guys i just had my 09 yz450f motor rebuilt. You can kick it for awhile and it wont start and then theres time where it will start. I can pop start it no problem or have my girlfriend pull me with her quad and it will start. Once its started it runs good but will stall out when idling for alittle. wont even start when its warm kicking it. Any ideas?

Wrong cam timing is a usual culprit.

Edited by mlatour

Clean out the carburetor jets. Replace the pilot jet.

+1 on cam timing and pilot circuit, but be sure on your valve specs too...

Edited by billygildark5007

Mine did that right after I rebuilt it. I had the valves a little on the tight side. I reshimed them and it started on the first kick.

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