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Discussion Starter · #1 ·
I have a '06 660 rhino. My cylinder is bored 102mm. Is a high compression piston a problem (11:1)? Or should I go with lower compression (9.9:1... I think)?

I also saw a 9.2:1, but not sure if that's available for the 660/686.
 

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Discussion Starter · #4 ·
so do you need better head studs and cometic gasket = no worries?

I thought I'd seen guys complain about head gaskets & heat with 686 big bores, and wondered if the high compression piston played a role in that.
 

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11-1 CP piston in mine... works great! 91 pump gas (but I think Nate will disagree.. ;))
My 700 with a 11:1 CP piston in it seems to run fine on 91 pump gas but always wondered what I should be running for octane and how much of a difference it would even make.
 
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