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Big Bore KitsBig Bore Kits

Dirt Bike Big Bore Kits

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

    TROY in CA

    Best mod ever

    This was buy far the best upgrade I did to this quad. Great fit.

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  • Cylinder Works Big Bore Cylinder Kit

    Cylinder Works Big Bore Cylinder Kit

    David in Texas

    365cc for KTM 350sxf...buyer beware

    Cylinder kit goes together nicely, but Cylinder Works gave no support after the installation of this kit. The kit obviously changes the fuel needed, which will require a ECU software change, they offer zero support except a jpeg of suggested settings.

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  • Dubach Racing Engine Relocation Kit

    Dubach Racing Engine Relocation Kit

    KEVIN in UT

    Easy Install

    Smooth instal.Take your time and follow the instructions.Made minor improvemen to the bike handling

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  • Athena Big Bore Kit

    Athena Big Bore Kit

    DAVID in CA

    Athena 290 big bore wr/yz

    I have ran this big bore for three years and have great success with it, makes great bottom end and mid range power. I have ran it on my 08 yz250f with a wr trans and rekluse clutch and hot cams, awesome woods bike.

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