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 Crankcase Bearing and Seal Kit 24-1006
MOOSE RACING
$62.95Your crankshaft is the heart of your engine—and it demands precision bearings that won't fail under high RPM stress. The MOOSE RACING Crankcase Bearing and Seal Kit 24-1006 delivers OEM-quality components engineered to reduce friction, minimize wear, and...A241006- SKU:
- A241006
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- UNITS:
- KIT
- PRODUCT NAME:
- BEARING KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CRANK
$62.95 -
MOOSE RACING Valve Shim - 7.48 x 2.15 - 5 pack MSE5PK748215
MOOSE RACING
$9.95Proper valve shim sizing is critical for maintaining correct valve clearances and ensuring optimal engine performance across your entire valve train. These forged 4140 steel shims are built to withstand repeated thermal cycling and adjustment cycles...09261877- SKU:
- 09261877
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- VALVE SHIM THICKNESS METRIC:
- 2.15 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- UNITS:
- 5 PACK
$9.95 -
MOOSE RACING Valve Seal Kit M80-80710
MOOSE RACING
$19.95Valve seal degradation is one of the most common causes of oil consumption and compression loss in high-mileage engines. The MOOSE RACING Valve Seal Kit M80-80710 replaces worn OEM seals with precision-engineered components that maintain consistent...09262831- SKU:
- 09262831
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- INTAKE
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- VITON
- APPLICATION:
- EXHAUST
- BASE COLOR:
- RED
- TYPE:
- VALVE STEM
- COLOR/FINISH:
- RED
- PRODUCT NAME:
- SEAL KIT
$19.95 -
MOOSE RACING Valve Seal Kit M80-80990
MOOSE RACING
$15.95Valve seal degradation causes oil burning, compression loss, and increased emissions—problems that compound quickly under racing conditions or high-mileage operation. The MOOSE RACING Valve Seal Kit M80-80990 replaces worn seals with precision-engineered...09262834- SKU:
- 09262834
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- APPLICATION:
- INTAKE
- COLOR/FINISH:
- RED
- PRODUCT NAME:
- SEAL KIT
- BASE COLOR:
- RED
- MATERIAL:
- VITON
- TYPE:
- VALVE STEM
$15.95 -
MOOSE RACING Intake Valve Kit M80-80950
MOOSE RACING
$307.95If you're running a high-performance engine, your intake valves are under constant thermal and mechanical stress. OEM titanium valves wear faster than necessary, forcing costly rebuilds and downtime. The MOOSE RACING Intake Valve Kit M80-80950 replaces...09262459- SKU:
- 09262459
- Availability:
- Ships Same Business Day
- Weight:
- 0.51 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE KIT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- STAINLESS STEEL
- UNITS:
- KIT
$307.95 -
MOOSE RACING Connecting Rod MR5399
MOOSE RACING
$474.95A connecting rod is the critical link between your piston and crankshaft—and a weak one will limit engine response and reliability under boost or high RPM. The MOOSE RACING MR5399, developed in partnership with CP-Carrillo, delivers professional-grade...09230306- SKU:
- 09230306
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- STYLE:
- HIGH PERFORMANCE
- UNITS:
- EACH
- ENGINE TYPE:
- 4-STROKE
- MATERIAL:
- PROPRIETARY ALLOY
- PRODUCT NAME:
- CONNECTING ROD
- RIDING STYLE:
- OFF-ROAD
$474.95 -
MOOSE RACING Connecting Rod MR9903
MOOSE RACING
$474.95Stock connecting rods are a bottleneck in any high-performance build—they flex under load, add unnecessary weight, and limit your engine's responsiveness. The MOOSE RACING MR9903, developed with CP-Carrillo, delivers the strength and precision you need...09230307- SKU:
- 09230307
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- UNITS:
- EACH
- PRODUCT NAME:
- CONNECTING ROD
- STYLE:
- HIGH PERFORMANCE
- MATERIAL:
- PROPRIETARY ALLOY
- RIDING STYLE:
- OFF-ROAD
$474.95 -
MOOSE RACING Top End Gasket Kit - KX 250 810457
MOOSE RACING
$45.89A top-end rebuild demands precision and reliability—corners cut here mean blown gaskets, oil weeps, and catastrophic engine failure. The MOOSE RACING Top End Gasket Kit delivers OEM-quality seals and gaskets at a fraction of dealer pricing, giving you...M810457- SKU:
- M810457
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
$45.89 -
MOOSE RACING Complete Motor Gasket Kit - KTM/Husqvarna 8080027
MOOSE RACING
$110.43A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise your build's integrity or your budget. The MOOSE RACING Complete Motor Gasket Kit delivers OEM-quality components at a fraction of the price, allowing...09346438- SKU:
- 09346438
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
$110.43 -
MOOSE RACING Complete Motor Gasket Kit - Honda CRF250 8080030
MOOSE RACING
$204.56A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise reliability or performance. The MOOSE RACING Complete Motor Gasket Kit eliminates the guesswork of sourcing individual components, giving you everything...09346439- SKU:
- 09346439
- Availability:
- Ships Same Business Day
- Weight:
- 0.31 LBS
- PRODUCT NAME:
- GASKET
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
$204.56 -
MOOSE RACING Complete Motor Gasket Kit without Seals 8110028
MOOSE RACING
$135.61A complete engine and transmission rebuild demands precision-fit gaskets that won't fail under boost or sustained RPM. The MOOSE RACING Complete Motor Gasket Kit delivers OEM-level reliability at a fraction of dealer pricing, letting you confidently...09346451- SKU:
- 09346451
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- TYPE:
- ENGINE
$135.61 -
MOOSE RACING Complete Motor Gasket Kit without Seals - YZ250 8110029
MOOSE RACING
$165.87A complete engine rebuild demands precision gaskets and seals that won't compromise your YZ250's reliability or performance. This Moose Racing kit eliminates the guesswork of sourcing individual components, giving you every gasket, o-ring, and valve seal...09346452- SKU:
- 09346452
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- TYPE:
- ENGINE
- PRODUCT NAME:
- GASKET
$165.87 -
MOOSE RACING Case Saver - RM125/250 03-161
MOOSE RACING
$23.95Engine case damage can sideline your bike faster than a DNF, and OEM plastic guards simply don't cut it on the track or trail. The MOOSE RACING Case Saver replaces flimsy stock protection with CNC-machined 6061 aluminum that absorbs impacts without...09500025- SKU:
- 09500025
- Availability:
- Ships Same Business Day
- Weight:
- 0.13 LBS
- BASE COLOR:
- SILVER
- MATERIAL:
- 6061 ALUMINUM
- UNITS:
- EACH
- PRODUCT NAME:
- CASE SAVER
- TYPE:
- ENGINE
- COLOR/FINISH:
- ALUMINUM
- RIDING STYLE:
- OFF-ROAD
$23.95 -
MOOSE RACING Washer/Snap Ring Counter Shaft 25-6013
MOOSE RACING
$33.95Countershaft fasteners are wear items that should be replaced during any front sprocket service to ensure proper retention and prevent catastrophic drivetrain failure. The MOOSE RACING Washer/Snap Ring Counter Shaft 25-6013 delivers OEM-equivalent...09350493- SKU:
- 09350493
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- 10 PACK
- APPLICATION:
- COUNTERSHAFT
- PRODUCT NAME:
- SNAP RING
$33.95 -
MOOSE RACING Water Pump Rebuild Kit 821364
MOOSE RACING
$35.25A failing water pump compromises engine cooling and risks catastrophic overheating—especially critical during high-performance racing or extended track sessions. The MOOSE RACING Water Pump Rebuild Kit 821364 gives you a complete, cost-effective solution...09345208- SKU:
- 09345208
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- PRODUCT NAME:
- REPAIR KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP
- UNITS:
- KIT
$35.25 -
MOOSE RACING Water Pump Rebuild Kit 821661
MOOSE RACING
$55.05A failing water pump can leave you stranded—or worse, destroy your engine. This MOOSE RACING rebuild kit gives you everything needed to restore your pump to factory specifications without the cost of a complete replacement. Whether you're prepping for...09345257- SKU:
- 09345257
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- PRODUCT NAME:
- REPAIR KIT
- TYPE:
- WATER PUMP
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$55.05 -
MOOSE RACING Water Pump Rebuild Kit 821264
MOOSE RACING
$37.45A failing water pump can sideline your engine before race day—corrosion, seal degradation, and bearing wear compromise cooling efficiency and create catastrophic failure risk. This MOOSE RACING rebuild kit supplies every gasket, seal, bearing, and snap...09345186- SKU:
- 09345186
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- PRODUCT NAME:
- REPAIR KIT
- TYPE:
- WATER PUMP
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$37.45 -
MOOSE RACING Water Pump Rebuild Kit 821273
MOOSE RACING
$48.77A failing water pump compromises your entire cooling system, risking catastrophic engine damage and costly downtime. The MOOSE RACING Water Pump Rebuild Kit 821273 delivers all the OEM-quality seals, bearings, and gaskets needed to restore your pump to...09345187- SKU:
- 09345187
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- REPAIR KIT
- TYPE:
- WATER PUMP
$48.77 -
MOOSE RACING Complete Motor Gasket Kit - CR500 808272
MOOSE RACING
$62.78A complete engine and transmission rebuild demands precision-fit gaskets and seals that won't compromise your work. This MOOSE RACING kit eliminates the frustration of sourcing individual components and potential fitment issues by bundling everything you...09340137- SKU:
- 09340137
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
- TYPE:
- ENGINE
$62.78 -
MOOSE RACING Top End Gasket Kit - 250SXF 810328
MOOSE RACING
$80.32A top-end rebuild demands precision gaskets and seals that won't compromise engine integrity or cost you a fortune. The MOOSE RACING Top End Gasket Kit delivers OEM-quality components at a fraction of the price, letting you restore your 250SXF's...09341009- SKU:
- 09341009
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
- TYPE:
- TOP END
- RIDING STYLE:
- STREET
$80.32
