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 to maximize compression, reduce blow-by, and support...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
$35.95Qty in Cart: 0Quantity:Price:$35.95Subtotal: -
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 pistons delivers precision-engineered ring geometry that...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 gravity-cast construction and nitride-coated components...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 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 M80-80890
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 precision-engineered components that maintain consistent...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
$15.95Qty in Cart: 0Quantity:Price:$15.95Subtotal: -
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 - 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 valve seal you need in one package, manufactured to...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
$131.46Qty in Cart: 0Quantity:Price:$131.46Subtotal: -
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 RACING kit eliminates the guesswork by bundling every...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 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 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 Racing piston rings are engineered to OEM...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 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
