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 Motor Seals - KX80/100 822291
MOOSE RACING
$22.53Engine seal degradation compromises compression, increases blow-by, and accelerates internal wear—replacement seals are non-negotiable for engine longevity. MOOSE Racing Motor Seals deliver OEM-equivalent performance at a fraction of dealership pricing,...09350055- SKU:
- 09350055
- Availability:
- Ships Same Business Day
- Weight:
- 0.23 LBS
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- ENGINE
- TYPE:
- OIL
- PRODUCT NAME:
- SEAL
- UNITS:
- SET
$22.53 -
MOOSE RACING Motor Seals KX80-100/RM100 822292
MOOSE RACING
$27.45Engine seals are critical to maintaining oil pressure, preventing leakage, and protecting internal components from contamination. OEM replacement seals often come with sticker shock, but Moose Racing delivers genuine-quality gasket and seal sets at a...09350056- SKU:
- 09350056
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- ENGINE
- TYPE:
- OIL
- UNITS:
- SET
$27.45 -
MOOSE RACING Motor Seals - KDX200 822295
MOOSE RACING
$33.37Engine and transmission seals are critical barriers against oil leakage and contamination—when they fail, you're looking at reduced performance, messy cleanup, and potential engine damage. The MOOSE RACING Motor Seals for KDX200 deliver OEM-equivalent...09350059- SKU:
- 09350059
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- UNITS:
- SET
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- SEAL
- APPLICATION:
- ENGINE
- TYPE:
- OIL
$33.37 -
MOOSE RACING Motor Seals - KDX 200/220 822296
MOOSE RACING
$30.68Engine and transmission seals are critical wear items that directly impact reliability and oil containment. The MOOSE RACING Motor Seals kit eliminates the guesswork of sourcing individual seals by delivering a complete OEM-spec replacement set at a...09350060- SKU:
- 09350060
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- ENGINE
- TYPE:
- OIL
- UNITS:
- SET
$30.68 -
MOOSE RACING Motor Seals - KX125 822298
MOOSE RACING
$32.65When you're rebuilding a KX125 engine, factory gasket and seal kits command premium prices—but Moose Racing delivers OEM-equivalent quality at a fraction of the cost. These seals are engineered from high-tech materials to handle the demands of both stock...09350062- SKU:
- 09350062
- Availability:
- Ships Same Business Day
- Weight:
- 0.23 LBS
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- SET
- APPLICATION:
- ENGINE
- TYPE:
- OIL
$32.65Qty in Cart: 0Quantity:Price:$32.65Subtotal: -
MOOSE RACING Valve Seal Kit M80-80440
MOOSE RACING
$19.95Valve seal degradation is one of the primary culprits behind oil consumption, blow-by, and loss of combustion efficiency—issues that compound quickly under sustained high RPM operation. The MOOSE RACING M80-80440 Valve Seal Kit addresses this with...09262830- SKU:
- 09262830
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- APPLICATION:
- INTAKE
- BASE COLOR:
- RED
- COLOR/FINISH:
- RED
- MATERIAL:
- VITON
- PRODUCT NAME:
- SEAL KIT
- TYPE:
- VALVE STEM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
$19.95 -
MOOSE RACING Intake Valve Kit M80-81100
MOOSE RACING
$196.95Factory titanium intake valves wear out faster than you'd like, especially under high-RPM conditions where thermal stress compounds quickly. The MOOSE RACING Intake Valve Kit replaces them with stainless steel Black Diamond valves that deliver up to 4x...09262732- SKU:
- 09262732
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- APPLICATION:
- INTAKE
- MATERIAL:
- STAINLESS STEEL
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- VALVE KIT
- UNITS:
- KIT
$196.95 -
MOOSE RACING Valve and Spring Kit M80-81110
MOOSE RACING
$196.95If you're running your engine hard, valve train durability becomes non-negotiable. The MOOSE RACING Valve and Spring Kit M80-81110 replaces wear-prone OEM titanium components with stainless steel Black Diamond intake valves engineered to last 4x longer...09262733- SKU:
- 09262733
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- APPLICATION:
- INTAKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- PRODUCT NAME:
- VALVE AND SPRING KIT
$196.95 -
MOOSE RACING Cylinder - Standard MSE50002
MOOSE RACING
$487.95A worn or damaged cylinder compromises compression, throttle response, and overall engine reliability—especially under high-load conditions. The MOOSE RACING Standard Cylinder restores your engine to OEM performance specifications with a precision-honed...09310465- SKU:
- 09310465
- Availability:
- Ships Same Business Day
- Weight:
- 2.65 LBS
- MATERIAL:
- ALUMINUM
- MATERIAL:
- CAST
- PRODUCT NAME:
- CYLINDER
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- CYLINDER BORE COATING:
- NICKEL-SILICON CARBIDE
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$487.95 -
MOOSE RACING Valve Shim - 9.48 x 3.15 - 5 pack MSE5PK948315
MOOSE RACING
$9.95Valve shim maintenance is critical for engine longevity and peak performance, and having the right shims on hand eliminates costly downtime during valve train adjustments. These MOOSE RACING shims are forged from durable 4140 cold rolled steel—not...09261967- SKU:
- 09261967
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
- VALVE SHIM THICKNESS METRIC:
- 3.15 MM
- RIDING STYLE:
- ATV
- TYPE:
- VALVE
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- OFF-ROAD
$9.95 -
MOOSE RACING Valve Shim - 9.48 x 3.20 - 5 pack MSE5PK948320
MOOSE RACING
$9.95Valve shim maintenance is critical to engine longevity and performance—incorrect shim selection leads to improper valve clearance, misfires, and accelerated wear on your valve train. This 5-pack from MOOSE Racing gives you the precision sizing you need...09261968- SKU:
- 09261968
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- TYPE:
- VALVE
- VALVE SHIM THICKNESS METRIC:
- 3.20 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- MATERIAL:
- ROLLED
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- UNITS:
- 5 PACK
$9.95 -
MOOSE RACING Valve Shim - 9.48 x 3.30 - 5 pack MSE5PK948330
MOOSE RACING
$9.95Valve train maintenance demands precision, and these MOOSE RACING shims deliver it. Forged from 4140 cold rolled steel—not sintered—they resist deformation under valve spring pressure and maintain consistent clearances over thousands of heat cycles. The...09261970- SKU:
- 09261970
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- VALVE SHIM THICKNESS METRIC:
- 3.30 MM
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- UNITS:
- 5 PACK
$9.95 -
MOOSE RACING Valve Shim - 9.48 x 3.35 - 5 pack MSE5PK948335
MOOSE RACING
$9.95Precision valve train maintenance starts with the right shims. If you're dialing in clearances on a built engine or refreshing a valve train, having quality shims in multiple sizes eliminates guesswork and saves you from multiple supply runs. These 4140...09261971- SKU:
- 09261971
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- UNITS:
- 5 PACK
- VALVE SHIM THICKNESS METRIC:
- 3.35 MM
- MATERIAL:
- ROLLED
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- RIDING STYLE:
- ATV
$9.95 -
MOOSE RACING Intake Valve Kit M30-31500
MOOSE RACING
$217.95If your engine is pushing hard on the track or street, your intake valves are working overtime—and OEM titanium components simply can't keep up with extended use. The MOOSE RACING Intake Valve Kit M30-31500 replaces those wear-prone originals with...09262432- SKU:
- 09262432
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PRODUCT NAME:
- VALVE KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- STAINLESS STEEL
- APPLICATION:
- INTAKE
$217.95 -
MOOSE RACING Valve and Spring Kit M30-31660
MOOSE RACING
$217.95If you're running high-mileage or high-boost applications, OEM titanium valves can become a limiting factor in reliability and longevity. The MOOSE RACING Valve and Spring Kit replaces them with stainless steel Black Diamond intake valves engineered to...09262433- SKU:
- 09262433
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PRODUCT NAME:
- VALVE AND SPRING KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- APPLICATION:
- INTAKE
$217.95 -
MOOSE RACING Valve and Spring Kit M30-31760
MOOSE RACING
$217.95If you're running high-mileage power through your engine, OEM titanium intake valves will eventually become a maintenance liability. The MOOSE RACING Valve and Spring Kit M30-31760 replaces them with stainless steel Black Diamond valves that extend valve...09262434- SKU:
- 09262434
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- PRODUCT NAME:
- VALVE AND SPRING KIT
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- INTAKE
$217.95 -
MOOSE RACING Valve and Spring Kit M30-32060
MOOSE RACING
$196.95If you're running extended engine cycles or high-mileage racing applications, OEM titanium valves become a wear liability. The MOOSE RACING Valve and Spring Kit M30-32060 replaces them with stainless steel Black Diamond intake valves engineered to extend...09262437- SKU:
- 09262437
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE AND SPRING KIT
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- UNITS:
- KIT
$196.95 -
MOOSE RACING Valve and Spring Kit M30-32260
MOOSE RACING
$196.95If you're running high-mileage track sessions or pushing your engine to the limit, OEM titanium intake valves won't cut it—they fatigue, fail, and force costly downtime. The MOOSE RACING Valve and Spring Kit M30-32260 replaces them with stainless steel...09262438- SKU:
- 09262438
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE AND SPRING KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
$196.95 -
MOOSE RACING Intake Valve Kit M40-40360
MOOSE RACING
$217.95OEM titanium intake valves are a known weak point in high-RPM applications, limiting both durability and flow potential. The MOOSE RACING Intake Valve Kit M40-40360 replaces them with stainless steel Black Diamond valves that extend valve train life by...09262440- SKU:
- 09262440
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PRODUCT NAME:
- VALVE KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- STAINLESS STEEL
- APPLICATION:
- INTAKE
$217.95Qty in Cart: 0Quantity:Price:$217.95Subtotal: -
MOOSE RACING Intake Valve Kit M30-32780
MOOSE RACING
$196.95If you're running high-mileage on your engine or pushing power levels beyond stock, OEM intake valves become a reliability bottleneck. The MOOSE RACING Black Diamond stainless steel conversion kit replaces those vulnerable stock components with...09263194- SKU:
- 09263194
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- APPLICATION:
- INTAKE
- MATERIAL:
- STAINLESS STEEL
- PRODUCT NAME:
- VALVE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$196.95Qty in Cart: 0Quantity:Price:$196.95Subtotal:
