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07 yfz 450 high compression with stock engine

So i changed out the cylinder and piston on the quad after i had smoke leaking out of the exhaust head. Ended up changing out the piston and cylinder. Wanted to do it soon anyway. Put it all back together and got two very loud pops on start up sounding like it came through the air filter, not really sure they were very loud. So i took it to a shop and they did a bunch of work and got it down to high compression and my engine is completely stock. They said its at 130 and should be between 70 and 90. Didnt wanna pay for them to take apart the engine. I took the head and cylinder off and everything looked good, had some buddies that know the engine well look at it and they said everything looks fine. Also i followed the service manual word for word. If anybody has any help that would be greatly appreciated. Thanks
 

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What kind of fuel did you run in it after the rebuild? If you put a HC piston in the engine without running race fuel of some sort it will detonate early and can grenade the engine. If it is in fact HC now try getting some C10from VP fuels or equivalent or something well above normal pump gas octane ratings. Drain tank and carb, refill with higher octane fuel and try again.
 

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What kind of fuel did you run in it after the rebuild? If you put a HC piston in the engine without running race fuel of some sort it will detonate early and can grenade the engine. If it is in fact HC now try getting some C10from VP fuels or equivalent or something well above normal pump gas octane ratings. Drain tank and carb, refill with higher octane fuel and try again.
I had 93 in it but its not a HC piston unless somehow i was sent a HC one, and now i have the compression down to 100 after taking the head off and putting it back on, and i have a spark.
 
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