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Big Bore KitsBig Bore Kits

Big Bore Kits from Rocky Mountain ATV/MC

High quality off road big bore kits.

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

  • Wiseco Big Bore 440 Kit

    Wiseco Big Bore 440 Kit

    KELLY S in CA

    great

    its great

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  • Athena Big Bore Kit

    Athena Big Bore Kit

    JUAN in AZ

    I bought a 478 Athena kit for my YFZ 450 last year around January put in about 30 hours of riding time and 3 oil changes, did perty good for a while but this last time I went to Glamis the piston Craked right down the middle so now I will be upgrading to a stroker kit.

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  • Cylinder Works Big Bore Cylinder Kit

    Cylinder Works Big Bore Cylinder Kit

    JEROME in QC

    wow!

    with hot cams and porting job, it is a HUGE difference... reached 42.39hp on my kfx400, very happy!

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  • Dubach Racing Engine Relocation Kit

    Dubach Racing Engine Relocation Kit

    Mike in ID

    DON'T HESITATE JUST BUY IT

    I WAS A LITTLE SCEPTICAL ABOUT THIS PRODUCT. HOW COULD MOVING THE MOTOR 2.5mm MAKE THAT MUCH DIFFERENCE? AFTER READING SEVERAL REVIEWS ON LINE AND IN MAGAZINES I DECIDED TO GIVE IT A TRY. I COMBINED THIS PRODUCT WITH A MAXISS EN FRONT TIRE AND WOW WHAT A DIFFERENCE. I AM 250 lbs AND DIDN'T HAVE NEAR THE TROUBLE WITH THE "DARTING" THAT ALOT OF OTHER YZ OWNERS COMPLAIN ABOUT. THIS TOOK ME FROM REALLY LIKING MY BIKE TO LOVING IT. DON'T HESITATE. JUST BUY IT. INSTALL WAS FAIRLY EASY USING THE VIDEO ON THE DRD WEBSITE.

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