Dirt Bike Engine
Dirt Bike Engine Parts at JJ Motorsports
Discover a full range of dirt bike engine components for rebuilding or upgrading your performance from JJ Motorsports. From crankshafts to cylinder heads and piston kits, these precision-engineered components ensure reliable performance. For additional upgrades, check out our full selection of off-road dirt bike parts to keep your engine running at peak efficiency on the track or trails.
Shop trusted brands like Wiseco for forged piston kits and K&N for high-flow oil filters. Explore related categories such as Dirt Bike Air and Fuel for intake upgrades or Dirt Bike Exhaust for complete systems.
Browse our in-stock inventory below with same-day shipping and expert support. Questions? Contact us for fitment advice!
- Product
- Qty in Cart
- Quantity
- Price
- Subtotal
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WINDEROSA Universal Gasket Sheet - 6 x 6 310101
WINDEROSA
$15.63WINDEROSA Universal Gasket Sheet - 6 x 609346883- SKU:
- 09346883
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- GASKET MATERIAL
$15.63 -
WINDEROSA Universal Gasket - 8 x 8 310102
WINDEROSA
$27.37WINDEROSA Universal Gasket - 8 x 809346884- SKU:
- 09346884
- Availability:
- Ships Same Business Day
- Weight:
- 0.66 LBS
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- PRODUCT NAME:
- GASKET MATERIAL
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$27.37 -
WINDEROSA Universal Gasket Kit 310113
WINDEROSA
$28.27WINDEROSA Universal Gasket Kit09346885- SKU:
- 09346885
- Availability:
- Ships Same Business Day
- Weight:
- 1.26 LBS
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
$28.27 -
WINDEROSA Universal Gasket Kit - 12 x 18 310114
WINDEROSA
$27.37WINDEROSA Universal Gasket Kit - 12 x 1809346886- SKU:
- 09346886
- Availability:
- Ships Same Business Day
- Weight:
- 0.91 LBS
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
$27.37 -
WINDEROSA Universal Gasket - Exhaust 310115
WINDEROSA
$20.55WINDEROSA Universal Gasket - Exhaust09346887- SKU:
- 09346887
- Availability:
- Ships Same Business Day
- Weight:
- 0.81 LBS
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- PRODUCT NAME:
- GASKET MATERIAL
- RIDING STYLE:
- STREET
- RIDING STYLE:
- WATERCRAFT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$20.55 -
WINDEROSA Gasket Kit - Standard Bore 810372
WINDEROSA
$76.74Made in the U.S.A.09346008- SKU:
- 09346008
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- BORE SIZE IMPERIAL:
- STANDARD
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CYLINDER
- UNITS:
- KIT
$76.74 -
WINDEROSA Standard Bore Gasket Kit 810670
WINDEROSA
$33.02Ready-to-install, direct bolt-on cylinders require no re-plating and look virtually identical to the OEM cylinders, Cylinder kits include matched Vertex pistons to ensure longevity, performance and reduced engine noise, Nickel Silicon Carbide plated for...09344049- SKU:
- 09344049
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- STYLE:
- STANDARD
- UNITS:
- KIT
- MATERIAL:
- NICKEL SILICON CARBIDE
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- TOP END
$33.02 -
WINDEROSA Standard Bore Gasket Kit 810414
WINDEROSA
$23.76Ready-to-install, direct bolt-on cylinders require no re-plating and look virtually identical to the OEM cylinders, Cylinder kits include matched Vertex pistons to ensure longevity, performance and reduced engine noise, Nickel Silicon Carbide plated for...09344053- SKU:
- 09344053
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- TOP END
- MATERIAL:
- NICKEL SILICON CARBIDE
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- STANDARD
$23.76 -
WINDEROSA Carb Base Gasket - Mikuni 38M 619123
WINDEROSA
$10.74Manufactured from compressed micropore material for ultimate sealing and durability, Replace worn or damaged base gaskets when doing a carb rebuild09342620- SKU:
- 09342620
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- WATERCRAFT
- STYLE:
- MIKUNI
- TYPE:
- CARBURETOR INTAKE
- BORE SIZE:
- 38,00 MM
- BORE SIZE METRIC:
- 38.00 MM
- MATERIAL:
- MICROPORE COMPOUND
- UNITS:
- 10 PACK
$10.74 -
WINDEROSA Carb Base Gasket - Mikuni 40M 619124
WINDEROSA
$10.35Manufactured from compressed micropore material for ultimate sealing and durability, Replace worn or damaged base gaskets when doing a carb rebuild09342621- SKU:
- 09342621
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- WATERCRAFT
- STYLE:
- MIKUNI
- PRODUCT NAME:
- GASKET
- UNITS:
- 10 PACK
- BORE SIZE:
- 40,00 MM
- TYPE:
- CARBURETOR INTAKE
- BORE SIZE METRIC:
- 40.00 MM
- MATERIAL:
- MICROPORE COMPOUND
$10.35 -
WINDEROSA Carb Base Gasket - Mikuni 44M 619125
WINDEROSA
$10.35Manufactured from compressed micropore material for ultimate sealing and durability, Replace worn or damaged base gaskets when doing a carb rebuild09342622- SKU:
- 09342622
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- WATERCRAFT
- STYLE:
- MIKUNI
- BORE SIZE:
- 44,00 MM
- BORE SIZE METRIC:
- 44.00 MM
- TYPE:
- CARBURETOR INTAKE
- PRODUCT NAME:
- GASKET
- UNITS:
- 10 PACK
- MATERIAL:
- MICROPORE COMPOUND
$10.35 -
WINDEROSA Complete Gasket Kit - Kawasaki 650 611104
WINDEROSA
$94.42Full engine gasket set includes bases, heads, intakes and crankshaft oil seals, Made in the U.S.A.PD810345- SKU:
- PD810345
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- TYPE:
- COMPLETE
- RIDING STYLE:
- WATERCRAFT
- PRODUCT NAME:
- GASKET SET
- UNITS:
- SET
$94.42 -
WINDEROSA Carb Base Gasket - Mikuni 46M 619126
WINDEROSA
$10.35Manufactured from compressed micropore material for ultimate sealing and durability, Replace worn or damaged base gaskets when doing a carb rebuild09342623- SKU:
- 09342623
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- BORE SIZE METRIC:
- 46.00 MM
- MATERIAL:
- MICROPORE COMPOUND
- TYPE:
- CARBURETOR INTAKE
- RIDING STYLE:
- WATERCRAFT
- STYLE:
- MIKUNI
- PRODUCT NAME:
- GASKET
- UNITS:
- 10 PACK
- BORE SIZE:
- 46,00 MM
$10.35 -
MOOSE RACING Washer/Snap Ring Counter Shaft 25-6016
MOOSE RACING
$34.95Always have the countershaft lock-washers and snap rings on hand for a front sprocket replacement09350495- SKU:
- 09350495
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- 10 PACK
- APPLICATION:
- COUNTERSHAFT
- PRODUCT NAME:
- WASHER
- RIDING STYLE:
- STREET
$34.95 -
MOOSE RACING Valve Shim - 7.48 x 2.25 - 5 pack MSE5PK748225
MOOSE RACING
$9.95Complete valve shim kits make it easier to maintain your valve train, Forged from 4140 cold rolled steel, not sintered, Laser-etched size on each shim for identification, A great addition to any mechanic's tool box, Refills sold to dealers in 5-packs;...09261879- SKU:
- 09261879
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- UNITS:
- 5 PACK
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- VALVE SHIM THICKNESS METRIC:
- 2.25 MM
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
$9.95 -
MOOSE RACING Valve Shim - 9.48 x 1.60 - 5 pack MSE5PK948160
MOOSE RACING
$9.95Complete valve shim kits make it easier to maintain your valve train, Forged from 4140 cold rolled steel, not sintered, Laser-etched size on each shim for identification, A great addition to any mechanic's tool box, Refills sold to dealers in 5-packs;...09261936- SKU:
- 09261936
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- MATERIAL:
- ROLLED
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- UNITS:
- 5 PACK
- VALVE SHIM THICKNESS METRIC:
- 1.60 MM
$9.95 -
MOOSE RACING Valve Shim - 9.48 x 2.90 - 5 pack MSE5PK948290
MOOSE RACING
$9.95Complete valve shim kits make it easier to maintain your valve train, Forged from 4140 cold rolled steel, not sintered, Laser-etched size on each shim for identification, A great addition to any mechanic's tool box, Refills sold to dealers in 5-packs;...09261962- SKU:
- 09261962
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- SNOW
- VALVE SHIM THICKNESS METRIC:
- 2.90 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- UNITS:
- 5 PACK
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
$9.95 -
MOOSE RACING Complete Motor Gasket Kit without Seals - CRF250R 8110030
MOOSE RACING
$216.37Moose can now handle all your gasket and seal needs at a fraction of OEM cost., High-tech materials provide unmatched reliability and performance, Rebuild the engine and transmission with total confidence as each set is designed for durability and...09346453- SKU:
- 09346453
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- TYPE:
- ENGINE
$216.37 -
MOOSE RACING Ignition Cover Gasket 816551
MOOSE RACING
$7.71Moose can now handle all your gasket and seal needs at a fraction of OEM cost, Rebuild the engine and transmission with total confidence as each set is designed for durability and accurate fit, Oil seals are genuine OEM replacement seals, These...09346576- SKU:
- 09346576
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- PRODUCT NAME:
- GASKET
- TYPE:
- IGNITION COVER
$7.71 -
MOOSE RACING Ignition Cover Gasket 816758
MOOSE RACING
$13.81Made in the U.S.A.09346170- SKU:
- 09346170
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- ENGINE TYPE:
- 4-STROKE
- UNITS:
- EACH
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- IGNITION COVER
$13.81
