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Discussion Starter · #1 ·
Well I need a new piston, and I am gonna go with a CP. But I have not decided on the comp ratio, 12:1 or 11:1. How much difference would there be and would the 12:1 always require ras gas?


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What is your elevation? I wouldn’t risk it with the 12:1 even at my elevation of riding, 6K-9K. Find an 11.5:1 as a sweet spot, otherwise just do the 11:1. What are your other supporting mods? Also I recommend an OEM head gasket.
 

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Discussion Starter · #3 ·
My elevation is about 300’ i had a cold tech in my previous raptor and really liked it but haven’t seen them available now. I plan on an aggressive trail port and a cam


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The duration of the cam matters. Greater duration means less effective compression, and can get away with a higher ratio piston. But if the intake, port work and cam lift do a better job filling the cylinder, then you get more effective compression
 

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If you can get e85 then jump to 14:1 and pick up 5hp. You will shock how fast the bike will be if not then 11:1 which is best on your elevation
Regarding camshafts. If you have stock head go with hotcam stage 3 and bore stock throttle body. That would get you to 65-66hp if you run 14:1 compression on e85 or racegas and +60hp if you run 11:1 compression on pumpgas.
 
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