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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HOT RODS Crankshaft Kit CBK0090
HOT RODS
$502.95If you're building a high-performance engine or restoring a classic with serious power ambitions, the HOT RODS Crankshaft Kit CBK0090 delivers the reliability and stroke length you need to maximize...09210335- SKU:
- 09210335
- Availability:
- Ships Same Business Day
- Weight:
- 8.00 LBS
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- CRANKSHAFT KIT
- TYPE:
- OEM
$502.95 -
HOT RODS Crankshaft Kit CBK0128
HOT RODS
$741.95Whether you're building a stroker engine or replacing a worn OEM crankshaft, the HOT RODS CBK0128 Crankshaft Kit delivers factory-matched precision with measurable performance gains. This complete...09210362- SKU:
- 09210362
- Availability:
- Ships Same Business Day
- Weight:
- 10.64 LBS
- PRODUCT NAME:
- CRANKSHAFT KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- OEM
$741.95 -
HOT RODS Crankshaft Kit CBK0129
HOT RODS
$835.95If you're building a high-performance engine that demands reliability under extreme conditions, the HOT RODS Crankshaft Kit CBK0129 delivers the precision and durability you need. This...09210363- SKU:
- 09210363
- Availability:
- Ships Same Business Day
- Weight:
- 13.10 LBS
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- CRANKSHAFT KIT
- TYPE:
- OEM
$835.95 -
HOT RODS Crankshaft Kit CBK0133
HOT RODS
$442.95A quality crankshaft is the foundation of engine reliability and performance—especially if you're pushing your build beyond stock parameters. The HOT RODS Crankshaft Kit CBK0133 arrives...09210365- SKU:
- 09210365
- Availability:
- Ships Same Business Day
- Weight:
- 6.60 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- CRANKSHAFT KIT
- TYPE:
- STROKER
$442.95 -
HOT RODS Crankshaft Kit CBK0134
HOT RODS
$370.95If you're building a high-displacement engine or need a crankshaft that matches OEM specifications without compromise, the HOT RODS Crankshaft Kit CBK0134 delivers factory-level precision with proven...09210366- SKU:
- 09210366
- Availability:
- Ships Same Business Day
- Weight:
- 6.07 LBS
- PRODUCT NAME:
- CRANKSHAFT KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- STROKER
$370.95 -
HOT RODS Crankshaft 4024
HOT RODS
$476.95A high-performance crankshaft built to withstand the demands of serious ATV racing and trail riding. The HOT RODS 4024 arrives factory-assembled and pre-trued to OEM specifications, eliminating...09210234- SKU:
- 09210234
- Availability:
- Ships Same Business Day
- Weight:
- 6.80 LBS
- RIDING STYLE:
- OFF-ROAD
- DISPLACEMENT:
- 125 CC
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- COLOR/FINISH:
- STEEL
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- FEATURES:
- STANDARD CRANKSHAFT
- MODEL:
- 2-CYCLE
- STROKE LENGTH METRIC:
- 54.50 MM
- TYPE:
- OEM STROKE
$476.95 -
HOT RODS Crankshaft 4025
HOT RODS
$595.95If you're building a long-stroke engine for your ATV or sport quad, you need a crankshaft engineered to handle the demands of extended stroke geometry without sacrificing reliability. The HOT RODS...09210235- SKU:
- 09210235
- Availability:
- Ships Same Business Day
- Weight:
- 6.85 LBS
- DISPLACEMENT:
- 144 CC TO 150 CC
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- STROKE LENGTH METRIC:
- 58.30 MM
- COLOR/FINISH:
- STEEL
- FEATURES:
- STANDARD CRANKSHAFT
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- MODEL:
- 2-CYCLE
- TYPE:
- OEM STROKE
$595.95 -
HOT RODS Crankshaft 4029
HOT RODS
$662.95If you're serious about maximizing your ATV's displacement and power output, a long-stroke crankshaft is one of the most effective modifications available—and Hot Rods 4029 eliminates the guesswork...09210238- SKU:
- 09210238
- Availability:
- Ships Same Business Day
- Weight:
- 7.24 LBS
- COLOR/FINISH:
- STEEL
- MATERIAL:
- 4140 STEEL
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 54.80 MM
- UNITS:
- ASSEMBLY
- FEATURES:
- STANDARD CRANKSHAFT
- TYPE:
- OEM STROKE
- DISPLACEMENT:
- 250 CC
- MODEL:
- 4-CYCLE
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
$662.95 -
HOT RODS Crankshaft 4030
HOT RODS
$476.95If you're building a long-stroke engine for your ATV or sport quad, the HOT RODS Crankshaft 4030 eliminates the guesswork and machine work typically required for this conversion. This complete...09210239- SKU:
- 09210239
- Availability:
- Ships Same Business Day
- Weight:
- 13.33 LBS
- COLOR/FINISH:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- ASSEMBLY
- DISPLACEMENT:
- 500 CC
- MODEL:
- 2-CYCLE
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- STROKE LENGTH METRIC:
- 79.00 MM
- MATERIAL:
- 4140 STEEL
- TYPE:
- OEM STROKE
- FEATURES:
- STANDARD CRANKSHAFT
$476.95Qty in Cart: 0Quantity:Price:$476.95Subtotal: -
HOT RODS Crankshaft 4046
HOT RODS
$515.95If you're running a long-stroke build on your ATV, a properly engineered crankshaft is non-negotiable—it's the foundation of reliability under sustained high RPM loads. The HOT RODS 4046 arrives...09210240- SKU:
- 09210240
- Availability:
- Ships Same Business Day
- Weight:
- 6.95 LBS
- DISPLACEMENT:
- 200 CC
- FEATURES:
- STANDARD CRANKSHAFT
- MODEL:
- 2-CYCLE
- TYPE:
- OEM STROKE
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- COLOR/FINISH:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 59.90 MM
$515.95Qty in Cart: 0Quantity:Price:$515.95Subtotal: -
HOT RODS Crankshaft 4096
HOT RODS
$489.95If you're building a long-stroke engine for your high-performance ATV, the HOT RODS Crankshaft 4096 eliminates the guesswork and machine work typically required for displacement increases. This...09210242- SKU:
- 09210242
- Availability:
- Ships Same Business Day
- Weight:
- 7.10 LBS
- MODEL:
- 4-CYCLE
- TYPE:
- OEM STROKE
- FEATURES:
- HEAVY DUTY CRANKSHAFT
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- DISPLACEMENT:
- 250 CC
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- STROKE LENGTH METRIC:
- 53.60 MM
- COLOR/FINISH:
- STEEL
- RIDING STYLE:
- OFF-ROAD
$489.95 -
HOT RODS Crankshaft 4097
HOT RODS
$476.95If you're building a long-stroke engine for your ATV, the HOT RODS Crankshaft 4097 eliminates the guesswork and machine work typically required for high-displacement builds. Factory-assembled and...09210243- SKU:
- 09210243
- Availability:
- Ships Same Business Day
- Weight:
- 7.45 LBS
- FEATURES:
- STANDARD CRANKSHAFT
- MODEL:
- 4-CYCLE
- TYPE:
- OEM STROKE
- DISPLACEMENT:
- 250 CC
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- STROKE LENGTH METRIC:
- 53.80 MM
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- COLOR/FINISH:
- STEEL
- RIDING STYLE:
- OFF-ROAD
$476.95 -
HOT RODS Crankshaft Assembly 4058
HOT RODS
$609.95If you're building a high-performance ATV engine or planning a long-stroke upgrade, the HOT RODS Crankshaft Assembly 4058 delivers factory-proven reliability without compromise. This complete...09210026- SKU:
- 09210026
- Availability:
- Ships Same Business Day
- Weight:
- 9.04 LBS
- COLOR/FINISH:
- STEEL
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- DISPLACEMENT:
- 250 CC
- FEATURES:
- STANDARD CRANKSHAFT
- MODEL:
- 2-CYCLE
- STROKE LENGTH METRIC:
- 72.00 MM
- TYPE:
- OEM STROKE
$609.95Qty in Cart: 0Quantity:Price:$609.95Subtotal: -
HOT RODS Crankshaft Assembly 4054
HOT RODS
$423.95If you're building a high-revving ATV engine or pushing your machine beyond stock limits, a quality crankshaft assembly is non-negotiable—it's the foundation of reliability under extreme conditions...09210027- SKU:
- 09210027
- Availability:
- Ships Same Business Day
- Weight:
- 6.22 LBS
- COLOR/FINISH:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 54.60 MM
- DISPLACEMENT:
- 125 CC
- MATERIAL:
- 4140 STEEL
- UNITS:
- ASSEMBLY
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- FEATURES:
- STANDARD CRANKSHAFT
- MODEL:
- 2-CYCLE
- TYPE:
- OEM STROKE
$423.95 -
HOT RODS Crankshaft Assembly 4041
HOT RODS
$476.95If you're building a long-stroke engine for your ATV, the HOT RODS Crankshaft Assembly 4041 eliminates guesswork and machine work by delivering a factory-assembled, trued crankshaft ready for bolt-in...09210016- SKU:
- 09210016
- Availability:
- Ships Same Business Day
- Weight:
- 6.55 LBS
- DISPLACEMENT:
- 125 CC
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- FEATURES:
- STANDARD CRANKSHAFT
- STROKE LENGTH METRIC:
- 54.60 MM
- TYPE:
- OEM STROKE
- MODEL:
- 2-CYCLE
- COLOR/FINISH:
- STEEL
- MATERIAL:
- 4140 STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- ASSEMBLY
$476.95Qty in Cart: 0Quantity:Price:$476.95Subtotal: -
HOT RODS Crankshaft Assembly 4050
HOT RODS
$515.95If you're building a long-stroke engine for your ATV, you need a crankshaft assembly engineered to handle the demands of increased displacement and extended power delivery. The HOT RODS Crankshaft...09210017- SKU:
- 09210017
- Availability:
- Ships Same Business Day
- Weight:
- 8.63 LBS
- MODEL:
- 4-CYCLE
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- DISPLACEMENT:
- 450 CC
- FEATURES:
- HEAVY DUTY CRANKSHAFT
- MATERIAL:
- 4140 STEEL
- STROKE LENGTH METRIC:
- 63.40 MM
- TYPE:
- OEM STROKE
- COLOR/FINISH:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- ASSEMBLY
$515.95 -
HOT RODS Crankshaft 4081
HOT RODS
$595.95If you're building a long-stroke engine for your ATV, the HOT RODS Crankshaft 4081 eliminates the guesswork and machine work typically required for displacement increases. This complete assembly...09210136- SKU:
- 09210136
- Availability:
- Ships Same Business Day
- Weight:
- 7.26 LBS
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- COLOR/FINISH:
- STEEL
- FEATURES:
- STANDARD CRANKSHAFT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- OEM STROKE
- MODEL:
- 4-CYCLE
- DISPLACEMENT:
- 250 CC
- MATERIAL:
- 4140 STEEL
- STROKE LENGTH METRIC:
- 53.60 MM
- UNITS:
- ASSEMBLY
$595.95 -
COMETIC Top End Gasket Kit - DT200 C7142
COMETIC
$32.95A failed top end gasket can cost you races, reliability, and credibility. The COMETIC C7142 kit delivers the sealing integrity and heat management you need to run hard—whether you're naturally...09340369- SKU:
- 09340369
- Availability:
- Ships Same Business Day
- Weight:
- 0.09 LBS
- PRODUCT NAME:
- GASKET KIT
- BORE SIZE METRIC:
- 68.00 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- TOP END
$32.95Qty in Cart: 0Quantity:Price:$32.95Subtotal: -
COMETIC Top End Gasket Kit - CR85 C7315
COMETIC
$34.95A quality top-end gasket kit is non-negotiable if you're rebuilding your CR85 engine or chasing reliability at the track. COMETIC's C7315 kit delivers the precision sealing you need to maintain...09340380- SKU:
- 09340380
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- PRODUCT NAME:
- GASKET KIT
- THICKNESS METRIC:
- 0.31 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- THICKNESS IMPERIAL:
- 0,012'
- TYPE:
- TOP END
- BORE SIZE METRIC:
- 52.00 MM
$34.95 -
COMETIC Top End Gasket Kit - YZ426F C7689
COMETIC
$47.95Top-end gasket failure compromises combustion sealing and power output—especially critical on high-compression 4-stroke builds. The COMETIC C7689 kit delivers factory-correct fitment for your YZ426F...09340392- SKU:
- 09340392
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- BORE SIZE METRIC:
- 95.00 MM
- PRODUCT NAME:
- GASKET KIT
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
$47.95Qty in Cart: 0Quantity:Price:$47.95Subtotal:
