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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WSM Ring Set 010-916
WSM
$43.40Piston ring sets are fundamental to engine reliability and performance—they seal combustion pressure, regulate oil consumption, and directly impact power output and longevity. The WSM Ring Set 010-916 delivers OEM-quality construction with tight...010916- SKU:
- 010916
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- RIDING STYLE:
- WATERCRAFT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- UNITS:
- SET
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON RING
$43.40 -
MOOSE RACING Valve Shim - 7.48 x 2.30 - 5 pack MSE5PK748230
MOOSE RACING
$9.95Precision valve train maintenance demands reliable, accurately-sized shims you can identify instantly—especially when you're deep in tuning or rebuilding. These MOOSE RACING shims eliminate guesswork with laser-etched sizing on each piece, letting you...09261880- SKU:
- 09261880
- 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
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- VALVE SHIM THICKNESS METRIC:
- 2.30 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
$9.95 -
MOOSE RACING Valve Shim - 7.48 x 2.80 - 5 pack MSE5PK748280
MOOSE RACING
$9.95Proper valve clearance is critical to engine performance and longevity—incorrect shim selection leads to valve float, compression loss, and potential catastrophic engine damage. MOOSE Racing valve shims give you precise, reliable valve train adjustment...09261890- SKU:
- 09261890
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- VALVE SHIM THICKNESS METRIC:
- 2.80 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
$9.95 -
MOOSE RACING Inner Clutch Cover Gasket 816194
MOOSE RACING
$18.03A leaking clutch cover gasket compromises engine integrity and invites oil seepage that can damage surrounding components. The MOOSE RACING Inner Clutch Cover Gasket 816194 delivers OEM-equivalent sealing performance at a fraction of OEM pricing, using...09346126- SKU:
- 09346126
- Availability:
- Ships Same Business Day
- Weight:
- 0.12 LBS
- UNITS:
- EACH
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH COVER
$18.03 -
MOOSE RACING Inner Clutch Cover Gasket 816251
MOOSE RACING
$20.86A leaking clutch cover gasket compromises engine sealing and invites oil contamination into critical drivetrain components. The MOOSE RACING Inner Clutch Cover Gasket 816251 delivers OEM-equivalent sealing performance at a fraction of OEM pricing, using...09346131- SKU:
- 09346131
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH COVER
- UNITS:
- EACH
$20.86 -
MOOSE RACING Inner Clutch Cover Gasket 816272
MOOSE RACING
$17.74A worn or damaged inner clutch cover gasket will compromise engine sealing and lead to oil leakage, performance loss, and potential internal damage. The MOOSE RACING 816272 delivers OEM-equivalent sealing reliability at a fraction of OEM pricing, using...09346136- SKU:
- 09346136
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH COVER
- PRODUCT NAME:
- GASKET
- UNITS:
- EACH
$17.74 -
MOOSE RACING Water Pump Rebuild Kit 821998
MOOSE RACING
$53.56A failing water pump doesn't just compromise cooling efficiency—it can leave you stranded mid-race or mid-drive with catastrophic engine damage. The MOOSE RACING Water Pump Rebuild Kit 821998 gives you everything needed to restore your pump to OEM...09346542- SKU:
- 09346542
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- REPAIR KIT
- TYPE:
- WATER PUMP
$53.56 -
MOOSE RACING Cylinder - Standard - KX450F MSE30011
MOOSE RACING
$402.95A damaged or worn cylinder directly kills your KX450F's performance and reliability. This MOOSE RACING replacement restores OEM-spec compression, heat management, and longevity without compromising your bike's original engineering. Get back to peak power...09310625- SKU:
- 09310625
- Availability:
- Ships Same Business Day
- Weight:
- 3.00 LBS
- MATERIAL:
- ALUMINUM
- CYLINDER BORE COATING:
- NICKEL-SILICON CARBIDE
- PRODUCT NAME:
- CYLINDER
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- MATERIAL:
- CAST
$402.95 -
MOOSE RACING Circlip MSE72071K
MOOSE RACING
$3.95Circlips are critical fastening components that prevent axial movement and keep internal assemblies secure under extreme load conditions. A quality circlip ensures reliability during high-rpm operation and reduces the risk of catastrophic component...09130190- SKU:
- 09130190
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- PRODUCT NAME:
- CIRCLIP
- RIDING STYLE:
- STREET
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- PISTON
- MATERIAL:
- STAINLESS STEEL
- UNITS:
- SET
$3.95 -
MOOSE RACING Intake Valve Kit M80-80850
MOOSE RACING
$307.95Factory titanium intake valves wear rapidly under sustained high-RPM operation, compromising flow efficiency and forcing expensive head rebuilds. The MOOSE RACING M80-80850 stainless steel conversion kit replaces worn or damaged valves with Black Diamond...09262457- SKU:
- 09262457
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- PRODUCT NAME:
- VALVE KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- STAINLESS STEEL
- APPLICATION:
- INTAKE
$307.95 -
MOOSE RACING Valve and Spring Kit M80-80960
MOOSE RACING
$217.95If you're running high-mileage or high-stress applications, OEM titanium valves can become a limiting factor in both longevity and flow characteristics. The MOOSE RACING Valve and Spring Kit M80-80960 replaces those components with stainless steel Black...09262460- SKU:
- 09262460
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE AND SPRING KIT
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- UNITS:
- KIT
$217.95 -
MOOSE RACING Clutch Cover Gasket 816143
MOOSE RACING
$15.23A leaking clutch cover gasket compromises both engine performance and reliability—oil seepage leads to contamination, wear, and potential catastrophic failure. The MOOSE RACING Clutch Cover Gasket 816143 delivers a precision-engineered OEM replacement...09341449- SKU:
- 09341449
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH COVER
- PRODUCT NAME:
- GASKET
- UNITS:
- EACH
$15.23 -
MOOSE RACING Ignition Cover Gasket 816144
MOOSE RACING
$8.80Ignition cover gaskets fail silently—until oil starts seeping onto your engine bay and performance suffers. The MOOSE RACING 816144 eliminates guesswork with OEM-spec sealing geometry at a fraction of dealership pricing. Whether you're rebuilding after a...09341450- SKU:
- 09341450
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- PRODUCT NAME:
- GASKET
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- IGNITION COVER
$8.80 -
MOOSE RACING Countershaft Sprocket Seal Kit - KTM 25-4005
MOOSE RACING
$24.95A worn countershaft sprocket seal compromises engine integrity and accelerates component wear—replacing it with OEM-quality parts is essential preventive maintenance. This MOOSE RACING kit delivers everything needed for a complete seal assembly,...09350432- SKU:
- 09350432
- Availability:
- Ships Same Business Day
- Weight:
- 0.12 LBS
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- COUNTERSHAFT
- PRODUCT NAME:
- SEAL KIT
- UNITS:
- KIT
$24.95 -
MOOSE RACING Top End Gasket Kit - Husqvarna/KTM 810959
MOOSE RACING
$71.55A top-end rebuild demands precision—incorrect gasket fitment or inferior seal materials will compromise compression, leak oil, and waste your time and money. The MOOSE RACING Top End Gasket Kit eliminates guesswork by including every OEM-spec gasket,...09344771- SKU:
- 09344771
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- GASKET
- TYPE:
- TOP END
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$71.55 -
MOOSE RACING Top End Gasket Kit - Kawasaki 810483
MOOSE RACING
$30.62A top-end rebuild demands precision components that won't compromise reliability or performance. The MOOSE RACING Gasket Kit delivers OEM-quality seals and gaskets at a fraction of the cost, letting you rebuild with confidence whether you're replacing a...09344772- SKU:
- 09344772
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- TOP END
$30.62 -
MOOSE RACING Top End Gasket Kit - Kawasaki 810484
MOOSE RACING
$30.06When you're rebuilding a top end, cutting corners on gaskets and seals is a guaranteed path to failure. The MOOSE RACING Top End Gasket Kit gives you everything needed for a complete, reliable rebuild at a fraction of OEM pricing—without sacrificing the...09344773- SKU:
- 09344773
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- TYPE:
- TOP END
- RIDING STYLE:
- OFF-ROAD
$30.06 -
MOOSE RACING Top End Gasket Kit - Yamaha 810642
MOOSE RACING
$54.04A quality top-end rebuild requires precision gaskets and seals that won't compromise your engine's integrity or cost you a fortune. The MOOSE RACING Top End Gasket Kit delivers OEM-equivalent performance at a fraction of the price, with every component...09344774- SKU:
- 09344774
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- UNITS:
- KIT
- RIDING STYLE:
- STREET
- TYPE:
- TOP END
$54.04 -
MOOSE RACING Top End Gasket - CRF250 810262
MOOSE RACING
$76.95A top-end rebuild demands precision gaskets and seals that won't compromise your engine's integrity or cost you a fortune. The MOOSE RACING gasket set gives you OEM-equivalent seals at a fraction of the price, letting you rebuild your CRF250 with...09340071- SKU:
- 09340071
- Availability:
- Ships Same Business Day
- Weight:
- 0.12 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
- TYPE:
- TOP END
$76.95 -
MOOSE RACING Top End Gasket - PW50 810601
MOOSE RACING
$13.39A top-end rebuild demands precision gaskets and seals that won't compromise your engine's integrity or your wallet. MOOSE RACING delivers OEM-equivalent performance at a fraction of the cost, with every gasket, O-ring, and seal you need for a complete,...09340078- SKU:
- 09340078
- Availability:
- Ships Same Business Day
- Weight:
- 0.28 LBS
- PRODUCT NAME:
- GASKET
- TYPE:
- TOP END
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
$13.39
