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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Rekluse Clutch Cover Honda CRF450R 2019-2024 RMS-0401002
REKLUSE
$0.00The stock clutch cover on your CRF450R can't handle the abuse of serious trail and race riding—rocks, logs, and hard impacts will eventually crack or dent it, compromising your bike's protection and...9402050- SKU:
- 9402050
- Availability:
- Ships Same Business Day
- Weight:
- 16.00 LBS
- COLOR/FINISH:
- ANODIZED
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
- COLOR/FINISH:
- BLACK
- MATERIAL:
- BILLET ALUMINUM
- PRODUCT NAME:
- COVER
- RIDING STYLE:
- STREET
- UNITS:
- EACH
$0.00Qty in Cart: 0Quantity:Price:$0.00Subtotal: -
Rekluse Clutch Cover Honda CRF250R 2018-2022 RMS-0401101
REKLUSE
$0.00Trail riding demands a clutch cover that can absorb punishment without compromising engine protection or oil capacity. The Rekluse RMS-0401101 delivers both durability and functional improvement over...9402103- SKU:
- 9402103
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- COLOR/FINISH:
- ANODIZED
- COLOR/FINISH:
- BLACK
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- MATERIAL:
- BILLET ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
$0.00Qty in Cart: 0Quantity:Price:$0.00Subtotal: -
MOOSE RACING Piston Kit MP3035
MOOSE RACING
$125.95Whether you're pushing peak boost or maximizing naturally aspirated output, piston durability and ring seal are non-negotiable. The MOOSE RACING Piston Kit MP3035 delivers race-proven construction...09106481- SKU:
- 09106481
- Availability:
- Ships Same Business Day
- Weight:
- 19.20 LBS
$125.95Qty in Cart: 0Quantity:Price:$125.95Subtotal: -
MOOSE RACING SEAL KIT COUNTERSHAFT BET 25-4047
MOOSE RACING
$25.95Countershaft seal failure leads to oil leakage, contamination, and accelerated wear on critical drivetrain components. The MOOSE RACING SEAL KIT COUNTERSHAFT BET 25-4047 delivers OEM-quality sealing...09351195- SKU:
- 09351195
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- COUNTERSHAFT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SEAL KIT
$25.95 -
WINDEROSA Top End Gasket Kit - Kawasaki 440 610101
WINDEROSA
$46.75A leaking top end gasket kit compromises combustion efficiency and invites coolant or oil contamination into your Kawasaki 440 engine—exactly what you don't need mid-season. The WINDEROSA 610101...PD812305- SKU:
- PD812305
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- TOP END
- UNITS:
- KIT
$46.75Qty in Cart: 0Quantity:Price:$46.75Subtotal: -
WINDEROSA Top End Gasket Kit - Kawasaki 550 610103
WINDEROSA
$51.03A top-end gasket kit is essential maintenance for any Kawasaki 550/610 engine—worn gaskets lead to compression loss, oil seepage, and decreased performance. WINDEROSA's comprehensive kit addresses...PD812325- SKU:
- PD812325
- Availability:
- Ships Same Business Day
- Weight:
- 0.19 LBS
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- TOP END
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
$51.03 -
WINDEROSA Top End Gasket Kit - Raider 701 610602
WINDEROSA
$67.95A failed top-end gasket can compromise your engine's compression and introduce coolant or oil contamination into the combustion chamber—both catastrophic for performance and engine longevity. The...PD812532- SKU:
- PD812532
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
$67.95 -
WORKS CONNECTION Engine Plug - Blue 24-490
WORKS CONNECTION
$31.95Stock engine plugs are functional but forgettable—and they're the first thing visible when you crack open your engine bay. The WORKS CONNECTION Engine Plug upgrades that visual real estate with...09500854- SKU:
- 09500854
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- STREET
- TYPE:
- ENGINE
- UNITS:
- SET
- COLOR/FINISH:
- BLUE
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- 6061 T-6 ALUMINUM
- COLOR/FINISH:
- ANODIZED
- PRODUCT NAME:
- PLUG
$31.95Qty in Cart: 0Quantity:Price:$31.95Subtotal: -
WINDEROSA Gasket - Complete - JS800SXR 611409
WINDEROSA
$127.95A complete gasket set is essential for any engine rebuild or overhaul on your JS800SXR—preventing oil leaks, coolant seepage, and combustion gas escape that compromise performance and reliability...09346560- SKU:
- 09346560
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- COMPLETE
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- ENGINE
- UNITS:
- KIT
$127.95Qty in Cart: 0Quantity:Price:$127.95Subtotal: -
WINDEROSA Standard Bore Gasket Kit 810213
WINDEROSA
$68.55Engine wear compromises both reliability and performance—cylinder bore degradation leads to compression loss, increased blowby, and accelerated piston wear. The WINDEROSA Standard Bore Gasket Kit...09341930- SKU:
- 09341930
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- BORE SIZE METRIC:
- 66.00 MM
- PRODUCT NAME:
- GASKET KIT
- STYLE:
- STANDARD
- TYPE:
- TOP END
- MATERIAL:
- NICKEL SILICON CARBIDE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$68.55Qty in Cart: 0Quantity:Price:$68.55Subtotal: -
WINDEROSA Jet Pump Seal Kit 623116
WINDEROSA
$15.03A worn jet pump seal kit compromises your watercraft's performance and creates costly internal damage. The WINDEROSA 623116 Jet Pump Seal Kit restores proper sealing between the impeller and housing,...09351122- SKU:
- 09351122
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- JET PUMP
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
- PRODUCT NAME:
- SEAL
$15.03Qty in Cart: 0Quantity:Price:$15.03Subtotal: -
WINDEROSA Gasket - Complete - JT1500 Ultra 611420
WINDEROSA
$362.94A complete gasket set is the foundation of engine reliability and performance. When you're rebuilding or servicing your JT1500 Ultra, using OEM-specification gaskets ensures proper sealing, prevents...09346564- SKU:
- 09346564
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- RIDING STYLE:
- WATERCRAFT
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- COMPLETE
- UNITS:
- KIT
- TYPE:
- ENGINE
$362.94Qty in Cart: 0Quantity:Price:$362.94Subtotal: -
WINDEROSA Gasket Kit - Standard Bore 810373
WINDEROSA
$71.97A complete gasket kit is essential for any engine rebuild or top-end refresh—it ensures reliable sealing across all critical surfaces and prevents costly coolant and oil leaks that compromise...09346009- SKU:
- 09346009
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- BORE SIZE IMPERIAL:
- STANDARD
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CYLINDER
- UNITS:
- KIT
$71.97 -
WORKS CONNECTION Engine Timing Plug - Red - Honda 24-508
WORKS CONNECTION
$46.95Stock engine timing plugs are often overlooked, but replacing them with precision-machined alternatives eliminates wobbling, improves reliability, and gives your engine bay a finished, professional...09500092- SKU:
- 09500092
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- COLOR/FINISH:
- ANODIZED
- MATERIAL:
- 6061 T-6 ALUMINUM
- COLOR/FINISH:
- RED
- TYPE:
- ENGINE
- UNITS:
- SET
- PRODUCT NAME:
- PLUG
- RIDING STYLE:
- OFF-ROAD
$46.95 -
MOOSE RACING Ring Set - For 95.5 mm Piston CPN2-2-3759
MOOSE RACING
$35.95A precision ring set is critical to maintaining proper compression, controlling blow-by, and extending engine life under high-boost or high-RPM conditions. The MOOSE RACING Ring Set is engineered for...09120242- SKU:
- 09120242
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- PRODUCT NAME:
- PISTON RING
- RIDING STYLE:
- OFF-ROAD
- PISTON SIZE METRIC:
- STANDARD
- RIDING STYLE:
- ATV
- UNITS:
- SET
$35.95Qty in Cart: 0Quantity:Price:$35.95Subtotal: -
MOOSE RACING Crankcase Bearing and Seal Kit 24-1008
MOOSE RACING
$83.95A crankshaft bearing failure doesn't just sideline your engine—it can cause catastrophic internal damage that ends a season or a rebuild investment. The MOOSE RACING 24-1008 kit delivers OEM-quality...A241008- SKU:
- A241008
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- PRODUCT NAME:
- BEARING KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- CRANK
$83.95 -
MOOSE RACING Motor Gasket Kit with Seal - 125SX 811330
MOOSE RACING
$121.59A complete engine and transmission rebuild requires precision-fit gaskets and seals that won't compromise your work—OEM-quality components at a fraction of dealership pricing. This Moose Racing kit...09341268- SKU:
- 09341268
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- TYPE:
- COMPLETE
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- TYPE:
- ENGINE
$121.59Qty in Cart: 0Quantity:Price:$121.59Subtotal: -
TMV Flywheel Weight 310FW1311
TMV
$181.95A heavier flywheel stores more rotational energy, delivering smoother throttle response and more predictable engine behavior under load—critical for precision driving and consistency lap-to-lap. The...09220088- SKU:
- 09220088
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- FEATURES:
- FLYWHEEL WEIGHT - 11 OZ.
- PRODUCT NAME:
- FLYWHEEL WEIGHT
- MATERIAL:
- 303 STAINLESS STEEL
$181.95Qty in Cart: 0Quantity:Price:$181.95Subtotal: -
TMV Flywheel Weight 310FW4113
TMV
$166.95A heavier flywheel increases rotational inertia, providing smoother acceleration and more stable engine dynamics under load—critical for consistent performance on the track or strip. The TMV...09220098- SKU:
- 09220098
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- PRODUCT NAME:
- FLYWHEEL WEIGHT
- FEATURES:
- FLYWHEEL WEIGHT - 13 OZ.
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- 303 STAINLESS STEEL
- UNITS:
- EACH
$166.95Qty in Cart: 0Quantity:Price:$166.95Subtotal: -
TMV Flywheel Weight 310FW2209
TMV
$152.95A heavier flywheel stores rotational energy more efficiently, reducing engine speed fluctuations and delivering smoother power delivery under acceleration and shifting. The TMV 310FW2209 achieves...09220099- SKU:
- 09220099
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- UNITS:
- EACH
- FEATURES:
- FLYWHEEL WEIGHT - 9 OZ.
- PRODUCT NAME:
- FLYWHEEL WEIGHT
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- 303 STAINLESS STEEL
$152.95Qty in Cart: 0Quantity:Price:$152.95Subtotal:
