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 Valve and Spring Kit M40-41455
MOOSE RACING
$196.95If you're running high-mileage track sessions or pushing your engine to the limit, OEM titanium intake valves will eventually cost you reliability and performance. The MOOSE RACING Valve and Spring...09263199- SKU:
- 09263199
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- PRODUCT NAME:
- VALVE
$196.95 -
MOOSE RACING Valve Seal Kit M40-41460
MOOSE RACING
$15.95Valve seal degradation is a common culprit behind oil consumption, blow-by, and performance loss—especially under high-heat or high-boost conditions. The MOOSE RACING Valve Seal Kit M40-41460...09263202- SKU:
- 09263202
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- PRODUCT NAME:
- SEAL KIT
- TYPE:
- VALVE STEM
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- BASE COLOR:
- RED
- MATERIAL:
- VITON
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- INTAKE
- COLOR/FINISH:
- RED
$15.95Qty in Cart: 0Quantity:Price:$15.95Subtotal: -
MOOSE RACING Intake Valve Kit M30-33680
MOOSE RACING
$217.95If you're running high-revving applications or extended racing seasons, OEM titanium intake valves will eventually fail you—often at the worst possible moment. The MOOSE RACING Stainless Steel Intake...09263303- SKU:
- 09263303
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$217.95 -
MOOSE RACING Magnetic Drain Plug DP107-1
MOOSE RACING
$23.95Metal debris circulating through your engine oil accelerates wear on critical components—bearings, cylinder walls, and valve trains. The MOOSE RACING Magnetic Drain Plug DP107-1 captures ferrous...09200045- SKU:
- 09200045
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- DRAIN
- COLOR/FINISH:
- RED
- PRODUCT NAME:
- PLUG
- RIDING STYLE:
- STREET
- UNITS:
- EACH
- DIAMETER - THREAD SIZE METRIC:
- M12 X 1.50 X 22 MM
- FEATURES:
- MAGNETIC
- MATERIAL:
- 7075 ALUMINUM
$23.95Qty in Cart: 0Quantity:Price:$23.95Subtotal: -
MOOSE RACING Magnetic Drain Plug DP108
MOOSE RACING
$23.95Engine wear accelerates when ferrous particles circulate through your oil system—particles that standard drain plugs simply miss. The MOOSE RACING Magnetic Drain Plug DP108 captures these metal...09200046- SKU:
- 09200046
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- FEATURES:
- MAGNETIC
- MATERIAL:
- 7075 ALUMINUM
- DIAMETER - THREAD SIZE METRIC:
- M12 X 1.50 X 20 MM
- RIDING STYLE:
- OFF-ROAD
- COLOR/FINISH:
- ORANGE
- PRODUCT NAME:
- PLUG
- UNITS:
- EACH
- TYPE:
- DRAIN
$23.95Qty in Cart: 0Quantity:Price:$23.95Subtotal: -
MOOSE RACING Magnetic Drain Plug DP115
MOOSE RACING
$23.95Metal particles inevitably accumulate in your engine oil—especially under high-performance driving conditions. The MOOSE RACING Magnetic Drain Plug DP115 captures ferrous debris before it can cause...09200047- SKU:
- 09200047
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- DIAMETER - THREAD SIZE METRIC:
- M16 X 1.50 X 12 MM
- MATERIAL:
- 7075 ALUMINUM
- PRODUCT NAME:
- PLUG
- UNITS:
- EACH
- COLOR/FINISH:
- SILVER
- FEATURES:
- NON-MAGNETIC
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- DRAIN
$23.95Qty in Cart: 0Quantity:Price:$23.95Subtotal: -
MOOSE RACING Magnetic Drain Plug DP120
MOOSE RACING
$23.95Metal particles inevitably circulate through your engine oil during normal operation—accelerating wear on critical components. The MOOSE RACING Magnetic Drain Plug DP120 captures ferrous debris...09200049- SKU:
- 09200049
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- PRODUCT NAME:
- PLUG
- UNITS:
- EACH
- MATERIAL:
- 7075 ALUMINUM
- FEATURES:
- MAGNETIC
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- DRAIN
- COLOR/FINISH:
- RED
- DIAMETER - THREAD SIZE METRIC:
- M10 X 1.50 X 22 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$23.95Qty in Cart: 0Quantity:Price:$23.95Subtotal: -
MOOSE RACING Valve Shim - 10.0 x 2.95 - 5 pack MSE5PK1000295
MOOSE RACING
$10.95Proper valve clearance is critical to engine performance and longevity—even slight deviations can cause compression loss, valve float, or premature wear. These MOOSE RACING valve shims give you...09261852- SKU:
- 09261852
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- MATERIAL:
- ROLLED
- VALVE SHIM THICKNESS METRIC:
- 2.95 MM
- OUTSIDE DIAMETER METRIC:
- 10.00 MM
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- UNITS:
- 5 PACK
- MATERIAL:
- STEEL
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
$10.95 -
MOOSE RACING Valve Shim - 10.0 x 3.15 - 5 pack MSE5PK1000315
MOOSE RACING
$10.95Valve shim maintenance demands precision—improper sizing compromises valve clearance and engine performance. These MOOSE RACING shims eliminate guesswork with laser-etched identification, ensuring...09261856- SKU:
- 09261856
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- OUTSIDE DIAMETER METRIC:
- 10.00 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- VALVE SHIM THICKNESS METRIC:
- 3.15 MM
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- MATERIAL:
- ROLLED
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- UNITS:
- 5 PACK
$10.95 -
MOOSE RACING Valve Shim - 7.48 x 1.25 - 5 pack MSE5PK748125
MOOSE RACING
$9.95Proper valve clearance is critical for engine performance, reliability, and longevity—and maintaining it requires the right shims on hand. The MOOSE RACING Valve Shim 5-pack gives you...09261859- SKU:
- 09261859
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- VALVE SHIM THICKNESS METRIC:
- 1.25 MM
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- STREET
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
MOOSE RACING Valve Shim - 7.48 x 2.85 - 5 pack MSE5PK748285
MOOSE RACING
$9.95Valve train maintenance demands precision, and these MOOSE RACING shims deliver it. Forged from 4140 cold rolled steel—not sintered material—they maintain tight tolerances through repeated thermal...09261891- SKU:
- 09261891
- 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
- UNITS:
- 5 PACK
- MATERIAL:
- ROLLED
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- MATERIAL:
- STEEL
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- VALVE SHIM THICKNESS METRIC:
- 2.85 MM
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
MOOSE RACING Valve Shim - 7.48 x 2.90 - 5 pack MSE5PK748290
MOOSE RACING
$10.95Valve shim maintenance demands precision components you can trust, and this 5-pack delivers exactly that. Forged from 4140 cold-rolled steel—not sintered—these shims resist deformation under valve...09261892- SKU:
- 09261892
- 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
- UNITS:
- 5 PACK
- VALVE SHIM THICKNESS METRIC:
- 2.90 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
$10.95 -
MOOSE RACING Valve Shim - 7.48 x 3.00 - 5 pack MSE5PK748300
MOOSE RACING
$9.95Proper valve clearance is critical to engine performance and longevity—too tight and you'll lose power, too loose and you risk valve float and catastrophic damage. MOOSE RACING valve shims give you...09261894- SKU:
- 09261894
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- VALVE SHIM THICKNESS METRIC:
- 3.00 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- UNITS:
- 5 PACK
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
MOOSE RACING Valve Shim - 7.48 x 3.05 - 5 pack MSE5PK748305
MOOSE RACING
$9.95Maintaining precise valve clearances is non-negotiable for engine longevity and consistent performance across heat cycles. These MOOSE RACING valve shims eliminate guesswork during valve train...09261895- SKU:
- 09261895
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- VALVE SHIM THICKNESS METRIC:
- 3.05 MM
- MATERIAL:
- ROLLED
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- UNITS:
- 5 PACK
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- STREET
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
MOOSE RACING Valve Shim - 9.48 x 2.85 - 5 pack MSE5PK948285
MOOSE RACING
$10.95Proper valve clearance is critical to engine performance and longevity—and maintaining accurate shim specs means the difference between a finely-tuned engine and costly valve train damage. MOOSE...09261961- SKU:
- 09261961
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- VALVE SHIM THICKNESS METRIC:
- 2.85 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- STREET
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- UNITS:
- 5 PACK
$10.95 -
MOOSE RACING Valve Shim - 9.48 x 2.95 - 5 pack MSE5PK948295
MOOSE RACING
$10.95Valve train maintenance requires precision—and guesswork doesn't belong in your engine bay. These MOOSE RACING valve shims give you the exact sizing and durability needed to dial in your valve...09261963- SKU:
- 09261963
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- VALVE SHIM THICKNESS METRIC:
- 2.95 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
$10.95 -
MOOSE RACING Gasket Material 403-5013
MOOSE RACING
$34.29A quality gasket material is fundamental to maintaining engine integrity and preventing costly fluid leaks that compromise performance and reliability. MOOSE RACING's gasket material delivers...09346977- SKU:
- 09346977
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- GASKET MATERIAL
$34.29 -
MOOSE RACING Cylinder - Standard MSECW20014
MOOSE RACING
$390.95A worn or damaged cylinder directly compromises compression, heat management, and overall engine reliability—making replacement essential for consistent performance. The MOOSE RACING Standard...09310969- SKU:
- 09310969
- Availability:
- Ships Same Business Day
- Weight:
- 1.57 LBS
- CYLINDER BORE COATING:
- NICKEL-SILICON CARBIDE
- CYLINDER DIAMETER METRIC:
- 97.00 MM
- DISPLACEMENT:
- 450 CC
- PRODUCT NAME:
- CYLINDER
- RIDING STYLE:
- OFF-ROAD
- CYLINDER DIAMETER:
- 97,00 MM
- BORE SIZE METRIC:
- STANDARD
- COLOR/FINISH:
- GRAY
- ENGINE TYPE:
- 4-CYCLE
- MATERIAL:
- ALUMINUM
- MATERIAL:
- CAST
- UNITS:
- EACH
$390.95 -
MOOSE RACING Top End Gasket Kit - YZF/WR250 810671
MOOSE RACING
$59.12When you're rebuilding a YZF/WR250 top end, gasket failure isn't an option. This Moose Racing kit gives you OEM-quality seals and gaskets at a fraction of the cost, with high-tech materials...M810671- SKU:
- M810671
- Availability:
- Ships Same Business Day
- Weight:
- 2.25 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
$59.12 -
MOOSE RACING Top End Gasket Kit - CR250R 810254
MOOSE RACING
$24.85A top-end rebuild demands precision—and cutting corners on gaskets and seals is how engines fail. The MOOSE RACING Top End Gasket Kit delivers OEM-quality components at a fraction of the cost,...M810254- SKU:
- M810254
- Availability:
- Ships Same Business Day
- Weight:
- 0.13 LBS
- UNITS:
- KIT
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
$24.85Qty in Cart: 0Quantity:Price:$24.85Subtotal:
