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10 YZ450F won't start after new head installed

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So I finally got my new GYTR ported head and 2mm over piston in. Everything went together fine and I was careful to re plug all connections.  Seems to have spark but doesn't start. 

I checked the cam timing and it's good. I do have a GYTR flywheel and the marks on it are different than stock and the same marks 180 degrees apart   I checked for TDC and installed it and then the cams .  Can it be 180 degrees off ?    

Does the crank sensor care? Still checking the simple stuff as well 

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Replace the GYT-R flywheel with your original.  There are two things you should be aware of.  One is that timing mark used to align camshafts on the '10 are NOT AT TDC.  This relates to the fact that the bore is offset 15mm forward.  The other is that you wouldn't be the first one to install a GYT-R flywheel on an early Gen3 YZ450 and run into this problem.

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I compared my original flywheel to the GYT-R one and realized that I was off by one tooth on the cam timing. My bad. The mark on the GYT-R was a tiny prick punch that you could hardly see thru the inspection hole. Fired right up after fixing this. Thanks. Now to break it in and find a new map for my ported head. My local track may be opening up for the year next weekend so I should be ready.

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