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orangeman100

2008 Yamaha BB - Issues After Rebuild

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Just rebuilt the top end on my 08 big bear 400. Piston rings wristpin gaskets. Got it back together it runs no back firing or popping but it takes a lil long to idle down and every now and then it kinda burps or misses for a split second and not often either I guess and then recovers just fine. Could the timing be off a tooth and cause this or would it be backfiring and popping a lot? Any other ideas?

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