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!
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- Qty in Cart
- Quantity
- Price
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MOOSE OFFROAD Gasket Kit with Oil Seal - Honda 8110043MSE
MOOSE OFFROAD
$112.56A complete engine and transmission rebuild demands precision—and compromised gaskets or seals will undermine even the best machine work. This MOOSE OFFROAD Gasket Kit gives you factory-correct sealing surfaces across your entire drivetrain, eliminating...09347197- SKU:
- 09347197
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$112.56 -
MOOSE OFFROAD Complete Motor Gasket Kit - Honda 808213MSE
MOOSE OFFROAD
$169.49A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise reliability or performance. MOOSE Offroad delivers a comprehensive kit with all necessary components at a fraction of OEM pricing, letting you rebuild...09347198- SKU:
- 09347198
- Availability:
- Ships Same Business Day
- Weight:
- 0.24 LBS
$169.49 -
MOOSE OFFROAD Top End Gasket Kit - Honda 8100042MSE
MOOSE OFFROAD
$106.05A top-end rebuild demands precision gasket-to-surface contact—any compromise in material quality or fit tolerance will result in oil weeping, combustion leakage, and accelerated wear. The MOOSE OFFROAD Top End Gasket Kit delivers OEM-specification...09347199- SKU:
- 09347199
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$106.05 -
MOOSE OFFROAD Complete Gasket Kit - Yamaha 8080028MSE
MOOSE OFFROAD
$154.90A complete engine and transmission rebuild demands precision gaskets that won't fail under load—and OEM replacements come with OEM pricing. The MOOSE OFFROAD Complete Gasket Kit delivers durability and accuracy at a fraction of the cost, letting you...09347200- SKU:
- 09347200
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
$154.90 -
MOOSE OFFROAD Complete Gasket Kit - Honda 8080040MSE
MOOSE OFFROAD
$86.16A complete engine and transmission rebuild demands precision-fit gaskets that won't compromise your reliability or budget. The MOOSE OFFROAD Complete Gasket Kit delivers OEM-quality sealing at a fraction of the cost, with every gasket and o-ring...09347201- SKU:
- 09347201
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$86.16 -
MOOSE OFFROAD Top End Gasket Kit - Suzuki 8100037MSE
MOOSE OFFROAD
$20.15A top-end rebuild demands precision—mismatched or worn gaskets compromise compression, invite oil weeping, and sabotage engine reliability. The MOOSE OFFROAD Top End Gasket Kit delivers a complete, OEM-quality solution at a fraction of dealer pricing,...09347202- SKU:
- 09347202
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$20.15Qty in Cart: 0Quantity:Price:$20.15Subtotal: -
MOOSE OFFROAD Clutch Cylinder Guard - Gas Gas/Husqvarna/KTM 13-1021
MOOSE OFFROAD
$42.95Hydraulic clutch cylinders are vulnerable to impact damage and chain strikes—two of the most common causes of mid-race failures. This MOOSE OFFROAD guard protects your clutch cylinder with CNC-machined aluminum construction while integrated knockdown...09500988- SKU:
- 09500988
- Availability:
- Ships Same Business Day
- Weight:
- 0.47 LBS
$42.95 -
MOOSE OFFROAD Slave Cylinder Rebuild Kit - Honda 18-6040
MOOSE OFFROAD
$29.95A leaking slave cylinder compromises both safety and clutch performance, leading to spongy engagement and potential hydraulic failure. This rebuild kit gives you a cost-effective alternative to full replacement, restoring your hydraulic system's...09500987- SKU:
- 09500987
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$29.95 -
MOOSE OFFROAD Exhaust Gasket Kit - Yamaha 823200MSE
MOOSE OFFROAD
$29.14Exhaust gaskets are critical wear items that deteriorate under thermal cycling and vibration, leading to exhaust leaks that compromise performance and increase emissions. The MOOSE OFFROAD Exhaust Gasket Kit delivers OEM-quality replacement gaskets and...09347189- SKU:
- 09347189
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
$29.14 -
MOOSE OFFROAD Exhaust Gasket Kit - Yamaha 823201MSE
MOOSE OFFROAD
$15.81A compromised exhaust seal costs you power and reliability. This Moose Offroad gasket kit eliminates leaks at critical connection points, restoring the backpressure and flow characteristics your engine was designed for. Whether you're running stock or...09347190- SKU:
- 09347190
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
$15.81 -
MOOSE OFFROAD Exhaust Gasket Kit - KTM 823195MSE
MOOSE OFFROAD
$16.37Exhaust gasket deterioration is one of the most common causes of performance loss and exhaust leaks on KTM 4-stroke engines. A failing gasket compromises seal integrity, allowing unburned fuel to escape and throwing off your air-fuel ratio—resulting in...09347191- SKU:
- 09347191
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
$16.37 -
MOOSE OFFROAD Exhaust Gasket Kit - Beta 823205MSE
MOOSE OFFROAD
$6.01A failing exhaust gasket compromises both performance and reliability—allowing exhaust gases to escape before they reach your powerband and introducing unwanted air leaks that throw off your fuel mapping. The MOOSE OFFROAD Exhaust Gasket Kit delivers...09347193- SKU:
- 09347193
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
$6.01Qty in Cart: 0Quantity:Price:$6.01Subtotal: -
REKLUSE Clutch Cover - Gas Gas/Husqvarna/KTM RMS-0413065
REKLUSE
$189.00Stock clutch covers fail under the rigors of aggressive riding—impacts with rocks, logs, and boot contact compromise both protection and oil containment. The REKLUSE Clutch Cover replaces this vulnerability with a robust, purpose-built design engineered...09402216- SKU:
- 09402216
- Availability:
- Ships Same Business Day
- Weight:
- 0.83 LBS
$189.00 -
HOT RODS Bottom End Kit - OE Crankshaft Kit - Husqvarna | KTM HR00178
HOT RODS
$679.95A complete bottom-end rebuild demands precision components and proper sealing—this kit eliminates the guesswork by bundling everything you need for crankshaft installation in one package. Whether you're refreshing a two-stroke after hard use or...09210951- SKU:
- 09210951
- Availability:
- Ships Same Business Day
- Weight:
- 12.10 LBS
$679.95Qty in Cart: 0Quantity:Price:$679.95Subtotal: -
MOOSE RACING Intake Valve M40-41650
MOOSE RACING
$196.95Stock intake valves are often the limiting factor in engine breathing efficiency—premature wear and suboptimal flow characteristics directly impact power output and reliability. The MOOSE RACING M40-41650 addresses this with precision engineering that...09263371- SKU:
- 09263371
- Availability:
- Ships Same Business Day
- Weight:
- 0.46 LBS
$196.95 -
MOOSE RACING Exhaust Valve M30-34010
MOOSE RACING
$196.95Stock exhaust valves reach their limits in high-performance applications, leading to premature wear and reduced engine reliability. The MOOSE RACING M30-34010 extends valve train life up to 4x longer than OEM titanium components while delivering improved...09263374- SKU:
- 09263374
- Availability:
- Ships Same Business Day
- Weight:
- 0.46 LBS
$196.95 -
MOOSE RACING Valve Seal Kit M30-34020
MOOSE RACING
$15.95Worn or degraded valve seals cause oil consumption, compression loss, and poor combustion efficiency—problems that compound quickly under racing or high-load conditions. The MOOSE RACING M30-34020 Valve Seal Kit delivers precision-engineered seals with...09263375- SKU:
- 09263375
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
$15.95 -
MOOSE RACING Valve Seal Kit M40-41680
MOOSE RACING
$15.95Engine valve seals naturally degrade under heat and combustion pressures, leading to oil leakage, blue smoke, and reduced compression. The MOOSE RACING Valve Seal Kit M40-41680 replaces worn seals with precision-engineered components that restore proper...09263376- SKU:
- 09263376
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
$15.95Qty in Cart: 0Quantity:Price:$15.95Subtotal: -
Wossner Crankshaft Assembly for KTM SX125 2016-2022 Husqvarna TC125 2016-2022 GasGas MC125 2021-2022 CS2070
WOSSNER
$342.00A worn or damaged crankshaft assembly compromises power transfer, throttle response, and engine longevity—particularly critical in 2-stroke competition machines where precision clearances determine performance and reliability. The Wossner CS2070 is...09210879- SKU:
- 09210879
- Availability:
- Ships Same Business Day
- Weight:
- 6.25 LBS
$342.00Qty in Cart: 0Quantity:Price:$342.00Subtotal: -
WOSSNER Crankshaft Assembly - Husaberg | Husqvarna | KTM CS2012
WOSSNER
$342.00A worn or damaged crankshaft assembly compromises engine reliability and performance—especially critical in high-demand riding conditions where precision matters. The WOSSNER CS2012 delivers OEM-equivalent quality with tighter tolerances and superior...09210880- SKU:
- 09210880
- Availability:
- Ships Same Business Day
- Weight:
- 6.95 LBS
$342.00
