New products

All new products

Suppliers

Big Bore Kits
There are 34 products.

Big Bore Kits

Big Bore kits for all makes of the Honda 50, xr, crf, z, z50, xr50, and crf50. Also manual clutch kits, high...More

Big Bore kits for all makes of the Honda 50, xr, crf, z, z50, xr50, and crf50. Also manual clutch kits, high volume oil pumps, and everything else needed to make your 50 faster!

  • 88cc stage 1 big bore kit for honda z50, ct70, xr70, xr50, and crf 50's
    Available

    88cc stage 1 big bore kit for honda for...

    Stage 1 88cc Big Bore kit for 92-99 Z50, 2000-present xr and crf 50's - Lightweight aluminum cylinder with steel sleeve- Cast in mounts on cylinder for aftermarket skid plates- Oversized cooling fins on cylinder for efficient heat dissipation- High compression 52mm piston with rings, pin, & clips (can still run...
    $139.99

    Add to cart
    View
  • 88cc stage 2 big bore kit for honda xr crf 50's and 70's
    Available

    88cc stage 2 big bore kit for honda Z, XR,...

    Stage 2 88cc Big Bore kit for 92-99 Z50 and 2000-present xr and crf 50 - 20mm Carburetor kit - Performance camshaft- Lightweight aluminum cylinder with steel sleeve- Cast in mounts on cylinder for aftermarket skid plates- Oversized cooling fins on cylinder for efficient heat dissipation- High compression 52mm...
    $249.99

    Add to cart
    View
  • 88cc stage 2 Vintage big bore kit for honda z50 and ct70
    Available

    88cc stage 2 Vintage big bore kit for...

    Vintage Stage 2 88cc Big Bore kit- Fits 1968-1981 honda z50, ct70, atc70, trx70, sl70, xl70- 20mm Carburetor- 52mm Piston and cylinder- Lightweight aluminum cylinder with steel sleeve- Cast in mounts on cylinder for aftermarket skid plates- Oversized cooling fins on cylinder for efficient heat dissipation
    $219.99

    Add to cart
    View
  • 88cc Race Head Big Bore Kit for honda Z50, xr crf 70, xr50, and crf 50's
    Available

    88cc Race Head Big Bore Kit for honda Z50,...

    88cc Race head kit for Your Honda 50 or Honda 70. This kit will drastically improve your overall performance on your bike. A stock honda 50 puts around 2.2hp to the ground and this kit will put you between 5.5-6hp to the ground and 30% more to the crank! Kit comes with fully assembled race head, performance cam,...
    $369.99

    Add to cart
    View
  • 88cc Race Head Vintage big bore kit for honda z50 and ct70
    Available

    88cc Race Head Vintage big bore kit for...

    50 Caliber Racing Race Head, 88cc Big Bore kit, and 20mm Carburetor Our Race Head has been updated for even more performance! It now has 25/22mm valves with better porting/flow. We also kept the combustion chamber the same size and changed the angle of the valves slightly. This will really wake up your stock engine...
    $374.99

    Add to cart
    View
  • 108cc stroker kit 1 for honda 50's and 70's
    Available

    108cc stroker kit 1 for honda 50's...

    Stroker Kit 1 Ready for more power? Convert your 88cc Race Head kit into a 108cc stroked out beast!! (Much more powerful than any of the chinese engines up to 125cc)
    $229.99

    Add to cart
    View
  • Available

    108cc stroker kit 2 for honda 50's...

    Complete 108cc Stroker kit for Honda crf and xr 50 and 70cc engines 1988 to current. Kit includes piston, race head, cylinder, cam, carburetor, throttle cable, gaskets, intake, crank, and filter.
    $499.00

    Add to cart
    View
  • Trail Bikes HD Auto Clutch

    Honda Trail Bikes Heavy Duty Auto Clutch kit. This clutch is a great improvement to your stock clutch. We recommend this kit with any upgraded/big bore motor. The stock clutch is designed for a stock motor and that's that. If you want reliablilty and power this is a must have performance upgrade. Fits 1992 to...
    $85.00

    View
  • Available

    52mm Head gasket kit

    52mm (88cc -108cc) and 54mm (117cc) Head gasket kit
    $12.00

    Add to cart
    View
  • Available

    Left and right case gaskets for Honda 50

    Left and right case gaskets for Honda 50, also fits all 50-125cc honda clone chinese engines.
    $12.00

    Add to cart
    View
  • Available

    47mm Head gasket and clutch gasket kit for...

    47mm 70cc Head gasket and clutch gasket kit for Honda 50 and Chinese Lifan motor.
    $18.00

    Add to cart
    View
  • Available

    Head gaskets 47mm and 52mm for Lifan Engines,

    47mm or 52m head gasket kit
    $11.00

    Add to cart
    View
  • Available

    Performance Intake

    Performance Intake for stock head or race head
    $32.00

    Add to cart
    View
  • Available

    High Volume Oil Pump - Vintage Honda 69-81...

    High Volume Oil Pump - Vintage Honda Z50 High volume oil pump for vintage Honda pit bikes and small ATVs. Delivers up to 3x the volume as the stock pump. We highly recommend upgrading your oil system when installing a big bore kit. Installation requires 2mm drill out of oiling outlet. 
    $32.00

    Add to cart
    View
  • Available

    High volume oil pump XR50 CRF50 82-Present

    High Volume oil pump for 1992 to current year Honda xr and crf 50. Fits all years of xr and crf, Delivers 3 times the amount of oil over stock pump.
    $26.00

    Add to cart
    View
  • Fits 150/160cc YX/GPX Engine's

    150/160cc YX/GPX Race Head V2 Upgrade Kit: - Race Head V2 - Roller rockers, 30mm intake valve, 24.5mm exhaust valve, 27mm intake port, 23mm exhaust port. (valves installed)
    $359.00

    View
  • Available

    Honda xr crf 50 rev box

    50 Caliber Rev Box. This rev box will remove the stock rev limiter and allow your pit bike to max out its performance and rpm's. Improved timing curve. Great bang for the buck! Fits all years of Honda xr50 and crf50
    $25.00

    Add to cart
    View
  • Available

    CDI 5 Pin Green Rev Box

    5 Pin CDI rev box
    $25.00

    Add to cart
    View
  • Available

    Gasket kit complete 52mm 110cc - 125cc

    50 Caliber Racing 52mm Gasket kit for 110cc and 125cc Lifan Engines Pit Bikes Atv Pocket Bike Go Karts and Mini Choppers
    $15.00

    Add to cart
    View
  • Available

    Gasket Head 47mm 70cc

    50 Caliber Racing 47mm Head Gasket Kit for 70cc Pit Bikes Atv Pocket Bike Go Karts and Mini Choppers
    $10.00

    Add to cart
    View
  • Available

    Gasket Head 52mm 110cc-125cc

    50 Caliber Racing 52mm Head Gasket Kit for 110cc and 125cc Pit Bikes Atv Pocket Bike Go Karts and Mini Choppers
    On sale! $10.00

    Add to cart
    View
  • Available

    Gasket kit Complete 47mm 70cc

    50 Caliber Racing 47mm Gasket kit for 70cc Lifan Engines Pit Bikes Atv Pocket Bike Go Karts and Mini Choppers
    $15.00

    Add to cart
    View
  • Available

    54mm Head gasket kit

    54mm (117cc) Head gasket kit
    $12.00

    Add to cart
    View
  • Available

    52mm 88cc 110cc 125cc Head gasket and...

    52mm 88cc 110cc 125cc Head gasket and clutch gasket kit for Honda 50 and Chinese Lifan motor.
    $18.00

    Add to cart
    View