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PistonsPistons

Pistons from Rocky Mountain ATV/MC

Your best source for piston kits and big bore kits at discount prices.

Latest Dirt Bike Pistons Reviews – You could win up to $500 for reviewing products!

  • Wiseco Piston Replacement Circlip

    Wiseco Piston Replacement Circlip

    KEN in WA

    wiseco, what can you say!!!

    great product just like every other wiseco product i've used

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  • Pro X High Compression Piston Kit

    Pro X High Compression Piston Kit

    Kyle in BC

    2008 YZ250F

    This piston has held up great. My YZ has hot cams and a hot rod crank and this piston completed my build. Bike pulls hard at all RPM's and has over 40 hours and still measures up great on the leak down tester. Would buy again if mine wears out but so far no need.

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  • Pro X Piston Wristpin Bearing

    Pro X Piston Wristpin Bearing

    SCOTT in CO

    Over 50 hours on it so far

    YZ250. I installed one with a Pro-X piston and have over 50 hours on the kit and still runs very strong with no mystery noises. Works very well.

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  • Pro X Piston Replacement Circlip

    Pro X Piston Replacement Circlip

    Dwayne in BC

    Nice price on spare circlips

    There are two circlips on one pack. Bought them incase I screwed up the install on the original clips but didn't need them in the end.

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  • Vertex Piston Kit Standard

    Vertex Piston Kit Standard

    MONTY in AB

    Great if you have sponsors

    I bought these for my Banshee since everything I read about them on-line was pretty good. The part nobody seems to mention on-line is that included in the box is the piston spec sheet advising you to replace the piston every 15-20 hours depending on CC of engine, there is a chart. Their Go-Kart pistons are rated 2 hours. Nice looking piston, but I can't afford new pistons after every long week-end of riding. Went back to OE piston, it made it 11 years on those. TECH NOTE: 20 HRS IS A PRETTY STANDARD SERVICE INTERVAL FOR A TWO-STROKE PISTON. ACTUAL PISTON LIFE WILL VARY WIDELY DUE TO RIDING STYLE, MAINTENANCE, ETC...

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  • Pro X Piston Kit

    Pro X Piston Kit

    DAVID in CA

    Poor quality

    Bought Pro-x instead of Vertex for the first time for my KTM 144sx. Piston was installed correctly into a good cylinder, synthetic premix, good jetting, heat cycles, etc. Piston scuffed and lost all compression after 15 min of riding. Installed the old Vertex (which was in great shape after 30hours ) and have been through 2 tanks of gas with the same premix and jetting, no problems. Pro-x said lack of lubrication and will not warranty. I will never buy their products again.

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