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Highest comp piston on pump fuel?

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I bought a used bike and will be doing a full rebuild (bottom end, new cam, cam chain, top end, valves) and want to put a high comp piston in it. The bike will also have a remap and stage 2 cam. Was thinking 14-1 but not sure if that's playing with fire. Pump fuel here is 93 octane so do I need to go 13.5-1 or can I get 14-1? Is there any real difference in power?

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13.5-1 and there's a night and day difference in how the bike runs on pump fuel, 91 octane in calofornia, and the leaded 110 vp gas. Worth the $8 a gallon when the bikes clean. But that's just my situation. 91 here is shit

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I have had detonation on the exhaust valve seat using 13.5:1 and 93 octane. The fuel from the pump has ethanol in Texas and most places in the USA. I would use race fuel with any compression above 13:1 now all I run is race fuel. U4.4 in my 2010 and mr12 in my 08 crf450. Both of my friends experienced detonation with the 13.5;1 ratio as well.

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you weigh like 135lbs?

so about 18-1 will work since the engine will never see full load  :lol:

but seriously.... 13.5 will be fine you may get away with more.

 

also trash bin that "stage 2" thing for a webcam or a rhc cam

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