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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WORKS CONNECTION Oil Fill Plug - Green 24-198
WORKS CONNECTION
$32.95Stock plastic oil fill plugs are prone to cracking under thermal stress and vibration—especially in high-performance or track applications. The WORKS CONNECTION Oil Fill Plug replaces that weak point...09500608- SKU:
- 09500608
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- RIDING STYLE:
- STREET
- BASE COLOR:
- GREEN
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- BASE FINISH:
- ANODIZED
- COLOR/FINISH:
- GREEN
- MATERIAL:
- 6061 T-6 ALUMINUM
- PRODUCT NAME:
- PLUG
- TYPE:
- OIL FILLER
- RIDING STYLE:
- ATV
$32.95 -
WSM Piston Kit - K1100 - +.25 mm 010-821-04PK
WSM
$98.28High-performance pistons are the foundation of reliable power delivery under sustained boost and RPM, and OEM units often compromise on thermal management and durability. The WSM K1100 Piston Kit...01082104P- SKU:
- 01082104P
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- BORE - OVERSIZE:
- +0,25 MM
- BORE SIZE METRIC:
- 80.00 MM
- MODEL:
- PLATINUM
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM
- BORE - OVERSIZE METRIC:
- +0.25 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- WATERCRAFT
$98.28 -
WSM Piston Kit - K1100 - +.5 mm 010-821-05PK
WSM
$93.60Whether you're chasing tighter tolerances in a rebuild or maximizing power output in a high-revving engine, OEM pistons often fall short of what serious builders demand. The WSM Piston Kit delivers...01082105P- SKU:
- 01082105P
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- BORE - OVERSIZE:
- +0,50 MM
- PISTON MATERIAL:
- ALUMINUM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 80.00 MM
- MODEL:
- PLATINUM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
$93.60Qty in Cart: 0Quantity:Price:$93.60Subtotal: -
On Sale
VESRAH Complete Gasket Kit - KE/KV 100 VG-444
VESRAH
MSRP: $31.49Now: $29.92Was: $31.49Engine gasket failure leads to oil leaks, compression loss, and catastrophic damage—often at the worst possible moment. The VESRAH VG-444 Complete Gasket Kit eliminates guesswork during top-end...VG444- SKU:
- VG444
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- SET
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
MSRP: $31.49Now: $29.92Was: $31.49 -
On Sale
VESRAH Complete Gasket Kit - DT100 VG-292
VESRAH
MSRP: $26.36Now: $25.04Was: $26.36Engine gasket failure doesn't just leak—it compromises compression, contaminates your oil, and forces you back into the shop. The VESRAH Complete Gasket Kit VG-292 provides all the sealing components...VG292- SKU:
- VG292
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- PRODUCT NAME:
- GASKET
- UNITS:
- SET
- TYPE:
- COMPLETE
MSRP: $26.36Now: $25.04Was: $26.36Qty in Cart: 0Quantity:Price:MSRP: $26.36Now: $25.04Was: $26.36Subtotal: -
BOYESEN Ignition Cover - Black - KTM SX SC-41AB
BOYESEN
$87.95The factory appearance of a professional-grade ignition cover matters when you're serious about your machine. This Boyesen cover seals properly to keep dirt and water out of your engine's...09401266- SKU:
- 09401266
- Availability:
- Ships Same Business Day
- Weight:
- 0.78 LBS
- RIDING STYLE:
- STREET
- COLOR/FINISH:
- BLACK
- PRODUCT NAME:
- COVER
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- IGNITION
- MATERIAL:
- ALUMINUM
- MODEL:
- FACTORY RACING
- COLOR/FINISH:
- POWDER-COATED
- UNITS:
- EACH
$87.95Qty in Cart: 0Quantity:Price:$87.95Subtotal: -
BOYESEN Ignition Cover - Gold - CR125 SC-01AM
BOYESEN
$87.95A quality ignition cover isn't just about aesthetics—it's critical engine protection. The Boyesen Factory Ignition Cover seals out dirt and water that can compromise internal components, while its...09400209- SKU:
- 09400209
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- COLOR/FINISH:
- POWDER-COATED
- MODEL:
- FACTORY RACING
- PRODUCT NAME:
- COVER
- TYPE:
- IGNITION
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- COLOR/FINISH:
- MAGNESIUM
- MATERIAL:
- ALUMINUM
$87.95Qty in Cart: 0Quantity:Price:$87.95Subtotal: -
BOYESEN Replacement Gasket - KTM CCG-44A
BOYESEN
$7.00A worn or compromised clutch cover gasket is a direct path to oil leaks and reduced clutch performance on your KTM. The BOYESEN CCG-44A replacement gasket eliminates the weak point in your factory...09343125- SKU:
- 09343125
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- MATERIAL:
- NITRILE RUBBER
- MODEL:
- FACTORY RACING
- UNITS:
- EACH
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH COVER
$7.00Qty in Cart: 0Quantity:Price:$7.00Subtotal: -
HOT RODS Crankshaft Assembly 4014
HOT RODS
$305.95If you're building a long-stroke engine for your ATV, the HOT RODS Crankshaft Assembly 4014 delivers the durability and precision you need without the machine work. This complete, factory-assembled...H117- SKU:
- H117
- Availability:
- Ships Same Business Day
- Weight:
- 4.10 LBS
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- COLOR/FINISH:
- STEEL
- DISPLACEMENT:
- 65 CC
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 41.60 MM
- FEATURES:
- STANDARD CRANKSHAFT
- MODEL:
- 2-CYCLE
- TYPE:
- OEM STROKE
$305.95 -
HOT RODS Water Pump Repair Kit - Honda WPK0006
HOT RODS
$34.95A leaking or failing water pump can quickly escalate into catastrophic engine damage, making timely repairs critical for both track and street applications. This HOT RODS repair kit supplies all...09342918- SKU:
- 09342918
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP REPAIR
- UNITS:
- KIT
$34.95 -
HOT RODS Water Pump Repair Kit - Honda WPK0007
HOT RODS
$63.95A leaking or failing water pump can quickly turn a reliable engine into an unreliable liability. This repair kit gives you the precision components—bearings, seals, and gaskets—needed to restore your...09342919- SKU:
- 09342919
- Availability:
- Ships Same Business Day
- Weight:
- 0.12 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP REPAIR
- UNITS:
- KIT
$63.95Qty in Cart: 0Quantity:Price:$63.95Subtotal: -
HOT RODS Water Pump Repair Kit - Honda WPK0008
HOT RODS
$54.95A leaking or failing water pump can quickly escalate from a minor inconvenience to catastrophic engine damage, especially under racing conditions or sustained high-performance driving. This repair...09342920- SKU:
- 09342920
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- TYPE:
- WATER PUMP REPAIR
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
$54.95 -
HOT RODS Crankshaft Assembly 4032
HOT RODS
$476.95If you're building a high-performance ATV engine or refreshing a tired bottom end, the HOT RODS Crankshaft Assembly 4032 delivers factory-proven reliability without the machine work. This complete,...H121- SKU:
- H121
- Availability:
- Ships Same Business Day
- Weight:
- 6.56 LBS
- COLOR/FINISH:
- STEEL
- FEATURES:
- STANDARD CRANKSHAFT
- STROKE LENGTH METRIC:
- 54.60 MM
- TYPE:
- OEM STROKE
- MATERIAL:
- 4140 STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- ASSEMBLY
- MODEL:
- 2-CYCLE
- DISPLACEMENT:
- 125 CC
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
$476.95 -
HOT RODS Crank Bearings K085
HOT RODS
$212.95A crankshaft is only as reliable as its bearings—and the HOT RODS K085 Crank Bearing Kit delivers the precision fit and durability required for high-RPM performance. These main bearing and seal kits...09240373- SKU:
- 09240373
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- APPLICATION:
- MAIN CRANKSHAFT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- BEARING
- TYPE:
- BALL
$212.95Qty in Cart: 0Quantity:Price:$212.95Subtotal: -
HOT RODS Crankshaft 4095
HOT RODS
$397.95If you're building a long-stroke engine for your ATV, you need a crankshaft engineered to handle the increased demands of extended stroke geometry. The HOT RODS Crankshaft 4095 arrives...09210215- SKU:
- 09210215
- Availability:
- Ships Same Business Day
- Weight:
- 7.15 LBS
- COLOR/FINISH:
- STEEL
- MATERIAL:
- 4140 STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- ASSEMBLY
- FEATURES:
- HEAVY DUTY CRANKSHAFT
- TYPE:
- OEM STROKE
- DISPLACEMENT:
- 250 CC
- MODEL:
- 4-CYCLE
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- STROKE LENGTH METRIC:
- 52.20 MM
$397.95 -
HOT RODS Crankshaft Kit CBK0119
HOT RODS
$595.95If you're building a high-performance engine or restoring a classic, you need a crankshaft assembly that's manufactured to exacting standards and ready to handle increased displacement or RPM. The...09210356- SKU:
- 09210356
- Availability:
- Ships Same Business Day
- Weight:
- 9.00 LBS
- PRODUCT NAME:
- CRANKSHAFT KIT
- TYPE:
- OEM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$595.95 -
HOT RODS Crankshaft Kit CBK0120
HOT RODS
$993.95The HOT RODS Crankshaft Kit CBK0120 delivers factory-spec performance with the durability of a purpose-built racing component. Whether you're rebuilding after catastrophic failure or upgrading for...09210357- SKU:
- 09210357
- Availability:
- Ships Same Business Day
- Weight:
- 13.65 LBS
- PRODUCT NAME:
- CRANKSHAFT KIT
- TYPE:
- OEM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$993.95Qty in Cart: 0Quantity:Price:$993.95Subtotal: -
HOT RODS Crankshaft Kit CBK0124
HOT RODS
$768.95If you're building a high-performance engine or refreshing a tired crankshaft, the HOT RODS Crankshaft Kit CBK0124 delivers factory-matched reliability with performance that meets or exceeds OEM...09210358- SKU:
- 09210358
- Availability:
- Ships Same Business Day
- Weight:
- 13.08 LBS
- TYPE:
- OEM
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- CRANKSHAFT KIT
- UNITS:
- KIT
$768.95 -
HOT RODS Crankshaft 4068
HOT RODS
$158.50If you're building a long-stroke engine for your ATV, you need a crankshaft engineered specifically for the application—not a compromised OEM unit that limits potential. The HOT RODS Crankshaft 4068...09210076- SKU:
- 09210076
- Availability:
- Ships Same Business Day
- Weight:
- 4.78 LBS
- COLOR/FINISH:
- STEEL
- DISPLACEMENT:
- 85 CC
- MATERIAL:
- 4140 STEEL
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 48.00 MM
- UNITS:
- ASSEMBLY
- MODEL:
- 2-CYCLE
- FEATURES:
- STANDARD CRANKSHAFT
- TYPE:
- OEM STROKE
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
$158.50 -
HOT RODS Crankshaft - Stroker 4166
HOT RODS
$316.95A stroker crankshaft transforms your ATV's engine into a powerhouse by increasing displacement and torque output without sacrificing reliability. The HOT RODS 4166 eliminates the machine work and...09210077- SKU:
- 09210077
- Availability:
- Ships Same Business Day
- Weight:
- 4.60 LBS
- COLOR/FINISH:
- STEEL
- DISPLACEMENT:
- 88 CC TO 103.5 CC
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- ASSEMBLY
- MATERIAL:
- 4140 STEEL
- MODEL:
- 2-CYCLE
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- STROKE LENGTH:
- 47,80 MM
- STROKE LENGTH METRIC:
- 47.80 MM
- FEATURES:
- STANDARD CRANKSHAFT
- TYPE:
- STROKER
$316.95
