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Discussion Starter #1
I am needing to bore my cylinder probally .040 and as i was looking at pistons
Stock is 8.5:1 and i seen a 9.5:1 and a 10.5:1.
has anyone ever had any problems going 9.5:1? i hear that 10.5:1 is very hard on the engine and i would like the extra HP!! but i want it to be a rider and not a work-on every weekend thing,i wouldnt mind a bi-yearly rebuild.

thanks
scott

2004 Honda Foreman 450ES
 

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Welcome to the forums! you can run a 10/5-1 and be way good will not be any harder on the motor than the 8-1 you are running now, the one behind the handle bars is whats hard on the motors, i run a 14-1 in my TRX450ER never have any problems but i do have to rum 110 oct fuel when you get above 13-5-1 you have to run highet oct fuel, do the 10/5-1 and a little cam and you will be happy.
 

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Agree. ^^^ the con of a high comp piston is that you will never go back to stock...well maybe thats not a con after all.. lol
 

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