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 Case Saver Guard - YZ250F CSG14
MOOSE RACING
$37.95Engine case damage can sideline your YZ250F mid-season and drain your wallet fast. The MOOSE RACING Case Saver Guard protects your crankcase from rock strikes and contact during aggressive riding...09500377- SKU:
- 09500377
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- COLOR/FINISH:
- BLACK
- COLOR/FINISH:
- RED
- PRODUCT NAME:
- GUARD
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- MATERIAL:
- NYLON
- TYPE:
- CASE SAVER
$37.95Qty in Cart: 0Quantity:Price:$37.95Subtotal: -
MOOSE RACING Case Saver Guard - Husqvarna CSG17
MOOSE RACING
$37.95Engine case damage can sideline your bike and drain your wallet fast. The MOOSE RACING Case Saver Guard shields your Husqvarna's vulnerable engine case from impact and debris without adding...09500380- SKU:
- 09500380
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- MATERIAL:
- NYLON
- PRODUCT NAME:
- GUARD
- UNITS:
- EACH
- COLOR/FINISH:
- BLACK
- COLOR/FINISH:
- RED
- TYPE:
- CASE SAVER
- RIDING STYLE:
- OFF-ROAD
$37.95Qty in Cart: 0Quantity:Price:$37.95Subtotal: -
MOOSE RACING Case Saver Guard - KX450F CSG20
MOOSE RACING
$37.95Engine case damage can sideline your KX450F mid-season, turning a minor crash into a costly repair. The MOOSE RACING Case Saver Guard protects your engine case from impact damage without the weight...09500383- SKU:
- 09500383
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- MATERIAL:
- NYLON
- PRODUCT NAME:
- GUARD
- TYPE:
- CASE SAVER
- UNITS:
- EACH
- COLOR/FINISH:
- BLACK
- COLOR/FINISH:
- RED
- RIDING STYLE:
- OFF-ROAD
$37.95Qty in Cart: 0Quantity:Price:$37.95Subtotal: -
MOOSE RACING Complete Motor Gasket Kit - KX125 808423
MOOSE RACING
$58.40A complete engine and transmission rebuild demands precision gasket sealing—any leak compromises performance and reliability. This Moose Racing kit eliminates the guesswork by bundling every gasket,...M808423- SKU:
- M808423
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
$58.40 -
MOOSE RACING Countershaft Sprocket Seal Kit - Kawasaki 25-4012
MOOSE RACING
$29.95Your countershaft seal assembly is your first line of defense against contamination and fluid loss in critical drivetrain components. A compromised seal leads to premature wear, increased friction,...09350439- SKU:
- 09350439
- Availability:
- Ships Same Business Day
- Weight:
- 0.13 LBS
- PRODUCT NAME:
- SEAL KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- COUNTERSHAFT
$29.95Qty in Cart: 0Quantity:Price:$29.95Subtotal: -
MOOSE RACING Countershaft Sprocket Seal Kit - Kawasaki 25-4017
MOOSE RACING
$23.95Countershaft seals are critical wear items that directly impact engine reliability and longevity. A worn or failed seal allows contamination and fluid loss, leading to increased friction and...09350443- SKU:
- 09350443
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- SEAL KIT
- UNITS:
- KIT
- APPLICATION:
- COUNTERSHAFT
- RIDING STYLE:
- OFF-ROAD
$23.95 -
MOOSE RACING Countershaft Sprocket Seal Kit - Yamaha 25-4044
MOOSE RACING
$29.95A worn countershaft sprocket seal compromises engine reliability and invites contamination into your transmission—exactly what you can't afford mid-race or mid-ride. The MOOSE RACING Countershaft...09350848- SKU:
- 09350848
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- APPLICATION:
- COUNTERSHAFT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- SEAL KIT
$29.95 -
MOOSE RACING Exhaust Gasket Kit 823166
MOOSE RACING
$14.99A failing exhaust gasket compromises both performance and durability, allowing exhaust gases to escape before they reach your muffler and creating dangerous leaks at critical connection points. This...09345347- SKU:
- 09345347
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- EXHAUST
- UNITS:
- KIT
$14.99 -
MOOSE RACING Valve Shim - 7.48 x 2.55 - 5 pack MSE5PK748255
MOOSE RACING
$9.95Proper valve clearance is critical to engine performance and longevity—even small deviations can cause valve float, reduced compression, and increased wear on your valve train. These MOOSE RACING...09261885- SKU:
- 09261885
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- UNITS:
- 5 PACK
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- ATV
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- VALVE SHIM THICKNESS METRIC:
- 2.55 MM
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
MOOSE RACING Water Pump Rebuild Kit 821423
MOOSE RACING
$56.48A failing water pump compromises your entire cooling system, risking engine overheating and catastrophic damage during competition or heavy use. The MOOSE RACING Water Pump Rebuild Kit 821423...09345216- SKU:
- 09345216
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP
- UNITS:
- KIT
- PRODUCT NAME:
- REPAIR KIT
$56.48Qty in Cart: 0Quantity:Price:$56.48Subtotal: -
MOOSE RACING Water Pump Rebuild Kit 821545
MOOSE RACING
$49.64A failing water pump can strand you on the track or leave you stranded on the road. Rather than replacing the entire assembly, this MOOSE RACING rebuild kit lets you restore your existing pump to...09345237- SKU:
- 09345237
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- PRODUCT NAME:
- REPAIR KIT
- TYPE:
- WATER PUMP
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
$49.64Qty in Cart: 0Quantity:Price:$49.64Subtotal: -
MOOSE RACING Exhaust Gasket Kit 823060
MOOSE RACING
$8.13A compromised exhaust gasket will rob your engine of power, create unwanted heat, and invite costly leaks that cascade into bigger problems. MOOSE RACING's Exhaust Gasket Kit 823060 delivers...09345280- SKU:
- 09345280
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- EXHAUST
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
$8.13 -
MOOSE RACING Exhaust Gasket Kit 823067
MOOSE RACING
$8.21A quality exhaust gasket kit is essential for maintaining proper seal integrity in your exhaust system—preventing dangerous exhaust leaks, reducing emissions, and preserving peak engine performance...09345284- SKU:
- 09345284
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- EXHAUST
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$8.21Qty in Cart: 0Quantity:Price:$8.21Subtotal: -
MOOSE RACING Exhaust Gasket Kit 823070
MOOSE RACING
$8.13MOOSE RACING Exhaust Gasket Kit09345287- SKU:
- 09345287
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- TYPE:
- EXHAUST
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- RIDING STYLE:
- OFF-ROAD
$8.13 -
MOOSE RACING Intake Valve Kit M30-32440
MOOSE RACING
$115.95OEM intake valves wear faster than they should, robbing you of horsepower and reliability during critical race moments. The MOOSE RACING Stainless Steel Intake Valve Kit replaces those weak points...09262932- SKU:
- 09262932
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PRODUCT NAME:
- VALVE KIT
- APPLICATION:
- INTAKE
- MATERIAL:
- STAINLESS STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$115.95Qty in Cart: 0Quantity:Price:$115.95Subtotal: -
MOOSE RACING Valve Shim - 9.48 x 3.25 - 5 pack MSE5PK948325
MOOSE RACING
$9.95Proper valve clearance is critical to engine performance and longevity, and maintaining it requires reliable, accurately sized shims. The MOOSE RACING Valve Shim 5-pack eliminates guesswork during...09261969- SKU:
- 09261969
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- VALVE SHIM THICKNESS METRIC:
- 3.25 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- UNITS:
- 5 PACK
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- STREET
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
MOOSE RACING Valve Seal Kit M80-82380
MOOSE RACING
$15.95Valve seal degradation is one of the most common causes of oil burning and compression loss in high-mileage engines. The MOOSE RACING Valve Seal Kit M80-82380 replaces worn OEM seals with...09263200- SKU:
- 09263200
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 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 M30-32795
MOOSE RACING
$15.95Valve seal degradation causes oil bypass, compression loss, and increased emissions—problems that compound quickly under racing conditions or high-mileage operation. The MOOSE RACING M30-32795...09263201- SKU:
- 09263201
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- MATERIAL:
- VITON
- APPLICATION:
- INTAKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- BASE COLOR:
- RED
- TYPE:
- VALVE STEM
- COLOR/FINISH:
- RED
- PRODUCT NAME:
- SEAL KIT
$15.95Qty in Cart: 0Quantity:Price:$15.95Subtotal: -
MOOSE RACING Valve Shim - 7.48 x 1.20 - 5 pack MSE5PK748120
MOOSE RACING
$9.95Precision valve train maintenance demands accuracy at every step—these forged steel shims eliminate guesswork during adjustment and setup. Whether you're dialing in a street build or maintaining a...09261858- SKU:
- 09261858
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- STREET
- VALVE SHIM THICKNESS METRIC:
- 1.20 MM
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- UNITS:
- 5 PACK
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
MOOSE RACING Water Pump Rebuild Kit 821232
MOOSE RACING
$47.89A failing water pump can compromise cooling system integrity and risk catastrophic engine damage. The MOOSE RACING Water Pump Rebuild Kit 821232 provides every gasket, seal, bearing, and snap ring...09345180- SKU:
- 09345180
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP
- UNITS:
- KIT
- PRODUCT NAME:
- REPAIR KIT
$47.89
