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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MOOSE RACING Exhaust Gasket Kit 823187
MOOSE RACING
$34.85Exhaust gasket degradation is one of the most common sources of power loss and unwanted emissions in high-performance engines. A failed or deteriorating gasket compromises seal integrity, allowing exhaust gases to escape before they reach your header or...09345352- SKU:
- 09345352
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- EXHAUST
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$34.85 -
MOOSE RACING Complete Gasket Kit 808374
MOOSE RACING
$125.59A complete engine and transmission rebuild demands precision-fit gaskets and seals that won't fail under sustained load. The MOOSE RACING Complete Gasket Kit 808374 delivers OEM-equivalent performance at a fraction of dealership pricing, giving you the...09345357- SKU:
- 09345357
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- TYPE:
- ENGINE
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- UNITS:
- KIT
$125.59 -
MOOSE RACING Complete Motor Gasket Kit - KX450F 808485
MOOSE RACING
$175.37A complete engine and transmission rebuild demands precision-fitted gaskets and seals that won't compromise your work or your engine's longevity. The MOOSE RACING Complete Motor Gasket Kit delivers OEM-quality sealing surfaces at a fraction of OEM...09345358- SKU:
- 09345358
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
$175.37 -
MOOSE RACING Valve Seal Kit M40-40160
MOOSE RACING
$15.95Factory valve seals degrade under sustained high heat and aggressive driving, leading to oil consumption, blow-by, and reduced ring seal integrity. The MOOSE RACING M40-40160 Valve Seal Kit replaces worn seals with precision-engineered components that...09262822- SKU:
- 09262822
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- VITON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- INTAKE
- COLOR/FINISH:
- RED
- PRODUCT NAME:
- SEAL KIT
- APPLICATION:
- EXHAUST
- BASE COLOR:
- RED
- TYPE:
- VALVE STEM
$15.95 -
MOOSE RACING Valve Seal Kit M40-40790
MOOSE RACING
$15.95Valve seal degradation is a silent killer of engine performance and longevity—worn seals allow oil to seep into combustion chambers, causing blow-by, reduced compression, and accelerated wear on rings and cylinders. The MOOSE RACING Valve Seal Kit...09262824- SKU:
- 09262824
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- INTAKE
- BASE COLOR:
- RED
- COLOR/FINISH:
- RED
- MATERIAL:
- VITON
- TYPE:
- VALVE STEM
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- SEAL KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$15.95 -
MOOSE RACING Cylinder - Standard MSE10006
MOOSE RACING
$402.95A worn or damaged cylinder directly impacts compression, heat management, and overall engine reliability—making replacement essential for consistent performance on the track or trail. The MOOSE RACING MSE10006 restores OEM specifications with a durable,...09310446- SKU:
- 09310446
- Availability:
- Ships Same Business Day
- Weight:
- 3.23 LBS
- MATERIAL:
- CAST
- PRODUCT NAME:
- CYLINDER
- MATERIAL:
- ALUMINUM
- UNITS:
- EACH
- CYLINDER BORE COATING:
- NICKEL-SILICON CARBIDE
- RIDING STYLE:
- OFF-ROAD
$402.95 -
MOOSE RACING Cylinder - Standard MSE20001
MOOSE RACING
$380.95A worn or damaged cylinder compromises compression, power delivery, and engine reliability—especially under racing conditions where tolerances matter. The MOOSE RACING Cylinder MSE20001 restores OEM performance with precision engineering and a durable...09310450- SKU:
- 09310450
- Availability:
- Ships Same Business Day
- Weight:
- 3.44 LBS
- MATERIAL:
- CAST
- PRODUCT NAME:
- CYLINDER
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- CYLINDER BORE COATING:
- NICKEL-SILICON CARBIDE
- MATERIAL:
- ALUMINUM
- UNITS:
- EACH
$380.95 -
MOOSE RACING Magnetic Drain Plug DP129
MOOSE RACING
$23.95Engine wear begins the moment oil circulates—and ferrous particles are the silent assassins. The MOOSE RACING Magnetic Drain Plug DP129 captures these metal filings before they recirculate through your bearings, cam lobes, and valve train, directly...09200065- SKU:
- 09200065
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- COLOR/FINISH:
- RED
- DIAMETER - THREAD SIZE METRIC:
- M8 X 1.25 X 20 MM
- PRODUCT NAME:
- PLUG
- UNITS:
- EACH
- FEATURES:
- MAGNETIC
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- DRAIN
- MATERIAL:
- 7075 ALUMINUM
$23.95 -
MOOSE RACING Piston Ring - For 57.95 mm Piston MSE55910005800
MOOSE RACING
$38.80A worn or damaged piston ring compromises combustion efficiency, increases blow-by, and forces your engine to work harder while losing power. MOOSE Racing piston rings are precision-engineered replacements that restore proper compression, reduce oil...09120845- SKU:
- 09120845
- Availability:
- Ships Same Business Day
- Weight:
- 1.01 LBS
- UNITS:
- EACH
- PRODUCT NAME:
- PISTON RING
- RIDING STYLE:
- OFF-ROAD
- PISTON SIZE METRIC:
- STANDARD
$38.80 -
MOOSE RACING Motor Gasket Kit with Seal - KDX/JR 811416
MOOSE RACING
$43.01A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise your work—Moose Racing delivers OEM-quality components at a fraction of dealer pricing. This comprehensive kit eliminates the tedious sourcing of...09340485- SKU:
- 09340485
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
$43.01 -
MOOSE RACING Top End Gasket Kit - RM125 810550
MOOSE RACING
$31.50When you're rebuilding an RM125 top end, every gasket and seal matters—a single leak or failure can compromise your entire engine. The MOOSE RACING Top End Gasket Kit delivers OEM-quality seals and gaskets at a fraction of OEM pricing, so you can...09340486- SKU:
- 09340486
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- PRODUCT NAME:
- GASKET
- TYPE:
- TOP END
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$31.50 -
MOOSE RACING Complete Motor Gasket Kit - RM125 808550
MOOSE RACING
$83.24A complete engine and transmission rebuild demands gaskets and seals that won't fail under load—and OEM replacements can devastate your budget. The MOOSE RACING Complete Motor Gasket Kit gives you factory-grade reliability at a fraction of dealership...09340487- SKU:
- 09340487
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- TYPE:
- COMPLETE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
- TYPE:
- ENGINE
$83.24 -
MOOSE RACING Motor Gasket Kit with Seal - RM125 811550
MOOSE RACING
$102.70A complete engine and transmission rebuild demands precision gaskets and seals that match OEM specifications—without the OEM price tag. This MOOSE RACING Motor Gasket Kit delivers genuine replacement seals and factory-engineered gaskets designed for...09340488- SKU:
- 09340488
- Availability:
- Ships Same Business Day
- Weight:
- 0.24 LBS
$102.70 -
MOOSE RACING Complete Motor Gasket Kit - TTR125 808640
MOOSE RACING
$73.01A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise your work. The MOOSE RACING Complete Motor Gasket Kit delivers OEM-quality replacement seals and gaskets at a fraction of OEM pricing, allowing you to...09340489- SKU:
- 09340489
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
- TYPE:
- ENGINE
$73.01 -
MOOSE RACING Motor Gasket Kit with Seal - TTR125 811640
MOOSE RACING
$88.62A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise your investment or performance. MOOSE Racing delivers OEM-equivalent fitment at a fraction of the cost, eliminating the need to source components...09340490- SKU:
- 09340490
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
$88.62 -
MOOSE RACING Top End Gasket Kit - YZ125 810641
MOOSE RACING
$28.10A top-end rebuild demands precision gaskets and seals that won't compromise your engine's integrity or your wallet. The MOOSE RACING Top End Gasket Kit gives you OEM-quality components at a fraction of OEM pricing, so you can confidently reassemble your...09340491- SKU:
- 09340491
- Availability:
- Ships Same Business Day
- Weight:
- 0.07 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET
$28.10 -
MOOSE RACING Slave Cylinder Rebuild Kit 18-6012
MOOSE RACING
$73.95A leaking slave cylinder doesn't just waste hydraulic fluid—it compromises clutch engagement and leaves you stranded. This MOOSE RACING rebuild kit gives you everything needed to restore a sealing slave cylinder without replacing the entire assembly,...09500897- SKU:
- 09500897
- Availability:
- Ships Same Business Day
- Weight:
- 0.12 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- SLAVE CYLINDER
$73.95 -
MOOSE RACING Slave Cylinder Rebuild Kit 18-6013
MOOSE RACING
$72.95A leaking slave cylinder compromises brake feel and can leave you stranded on track or trail. This MOOSE RACING rebuild kit gives you everything needed to restore a worn slave cylinder to like-new sealing performance, eliminating the guesswork and cost...09500898- SKU:
- 09500898
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- SLAVE CYLINDER
- RIDING STYLE:
- STREET
$72.95 -
MOOSE RACING Slave Cylinder Rebuild Kit - KTM 18-6004
MOOSE RACING
$44.95A leaking slave cylinder compromises clutch control and can strand you trackside or on the trail. This MOOSE RACING rebuild kit restores your hydraulic seal integrity with OEM-quality components, eliminating the need for a complete cylinder replacement...09500763- SKU:
- 09500763
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- TYPE:
- SLAVE CYLINDER
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- REBUILD KIT
- UNITS:
- KIT
$44.95 -
MOOSE RACING Slave Cylinder Rebuild Kit 18-6009
MOOSE RACING
$44.95A leaking slave cylinder compromises brake feel and can leave you stranded. This complete rebuild kit from MOOSE RACING provides all the OEM-specification seals and components needed to restore your slave cylinder to factory performance without replacing...09500768- SKU:
- 09500768
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- TYPE:
- SLAVE CYLINDER
- PRODUCT NAME:
- REBUILD KIT
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$44.95
