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 Ring Set - For 77 mm Piston CP7700C
MOOSE RACING
$35.95A quality ring set is critical to maintaining cylinder sealing and combustion efficiency in high-performance engines. The MOOSE RACING Ring Set for the CP7700C piston delivers precision engineering...09120241- SKU:
- 09120241
- Availability:
- Ships Same Business Day
- Weight:
- 0.03 LBS
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 4-STROKE
- PISTON SIZE METRIC:
- STANDARD
- PRODUCT NAME:
- PISTON RING
- UNITS:
- SET
$35.95 -
MOOSE RACING Ring Set - For 95 mm Piston CPN2-3740
MOOSE RACING
$35.95A quality ring set is the foundation of reliable piston performance, directly impacting compression, blow-by, and longevity in high-demand racing applications. The MOOSE RACING Ring Set for 95 mm...09120244- SKU:
- 09120244
- Availability:
- Ships Same Business Day
- Weight:
- 0.07 LBS
- PRODUCT NAME:
- PISTON RING
- RIDING STYLE:
- OFF-ROAD
- PISTON SIZE METRIC:
- STANDARD
- UNITS:
- SET
$35.95 -
MOOSE RACING Piston Kit - 44.97 mm MSE23430CD
MOOSE RACING
$89.20A quality piston kit is fundamental to engine reliability and longevity, especially in high-demand racing and performance applications. The MOOSE RACING Piston Kit delivers proven durability through...09102717- SKU:
- 09102717
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 44.97 MM
- RIDING STYLE:
- OFF-ROAD
$89.20Qty in Cart: 0Quantity:Price:$89.20Subtotal: -
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...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
$10.95Proper 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...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
$10.95Qty in Cart: 0Quantity:Price:$10.95Subtotal: -
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...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 M80-80890
MOOSE RACING
$15.95OEM valve seals degrade under sustained heat and combustion pressures, leading to oil consumption, blowby, and performance loss. The MOOSE RACING Valve Seal Kit M80-80890 replaces worn seals with...09262833- SKU:
- 09262833
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- SEAL KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- BASE COLOR:
- RED
- MATERIAL:
- VITON
- TYPE:
- VALVE STEM
- APPLICATION:
- INTAKE
- COLOR/FINISH:
- RED
- RIDING STYLE:
- ATV
$15.95 -
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...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...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...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...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...M810457- SKU:
- M810457
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
$45.89Qty in Cart: 0Quantity:Price:$45.89Subtotal: -
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...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...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 - Honda CRF450 8080034
MOOSE RACING
$131.46A complete engine and transmission rebuild demands gaskets and seals that match OEM specifications without the OEM price tag. This MOOSE RACING kit delivers exactly that—every gasket, o-ring, and...09346440- SKU:
- 09346440
- Availability:
- Ships Same Business Day
- Weight:
- 0.31 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
$131.46 -
MOOSE RACING Top End Gasket Kit - Honda 8100028
MOOSE RACING
$56.32A complete top-end gasket kit is essential when rebuilding your engine—whether you're replacing a piston, performing routine maintenance, or seeking a cost-effective compression boost. This MOOSE...09346446- SKU:
- 09346446
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- DISPLACEMENT:
- 125 CC
- TYPE:
- TOP END
$56.32Qty in Cart: 0Quantity:Price:$56.32Subtotal: -
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...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...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 Piston Ring - For 66.34/66.35 mm Piston MSE55910006640
MOOSE RACING
$32.95A worn or damaged piston ring directly compromises compression, oil control, and power output—making ring replacement one of the most critical maintenance tasks for any high-performance engine. MOOSE...09120414- SKU:
- 09120414
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- OFF-ROAD
- PISTON SIZE METRIC:
- STANDARD
- PRODUCT NAME:
- PISTON RING
- UNITS:
- EACH
$32.95Qty in Cart: 0Quantity:Price:$32.95Subtotal: -
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...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
