YZ450F 2007 Hard to start

My YZ450F 2007 is difficult to kick start and it only gets worst when the engine is hot. On top of that, the engine gets extremely stubborn, needing well over 15 strokes to get the engine running (with or without using the hot start lever). When the engine is running, it works fine. The piston, rings and cylindre were recently changed and the bike has been driven about 4-5 hours since then. Grateful for any good advice. Thanks.

Common problem.

You need to adjust the valves

There wll be one out of wack

Kinda hard to do, you need to have good feel and be carfull not to force the feeler gauge in because of the light spring preasure.

you need to have good feel and be carfull not to force the feeler gauge in because of the light spring preasure.

+1. Good call. The first time i shimmed my valves i couldnt believe how soft the springs were. Kinda makes me wanna get some kibblewhite springs. If your valves happen to be in spec,then i would check your jetting. I always turn the gas on,wait 1 min,choke it,give the throttle one quick twist, and she fires on the first kick.

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