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
- Subtotal
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VERTEX Piston Kit VTKTC23259B
VERTEX
$314.95A high-performance piston kit must withstand extreme combustion pressures and thermal cycling without sacrificing reliability—especially if you're pushing peak horsepower. The VERTEX Piston Kit...09103751- SKU:
- 09103751
- Availability:
- Ships Same Business Day
- Weight:
- 1.70 LBS
$314.95 -
VERTEX Piston Kit 23711B
VERTEX
$302.95A quality piston kit is the foundation of reliable engine performance, and the VERTEX Piston Kit 23711B delivers the durability and precision needed for both street and race applications. Whether...09102594- SKU:
- 09102594
- Availability:
- Ships Same Business Day
- Weight:
- 0.71 LBS
$302.95 -
VERTEX Piston Kit - Standard 22983B
VERTEX
$242.95If you're building or rebuilding an engine that demands reliability under sustained high RPM and load, OEM pistons often can't keep pace. The VERTEX Piston Kit 22983B delivers the durability and...09101043- SKU:
- 09101043
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
$242.95 -
Wiseco Piston Kit 51.00 mm Yamaha YZ 80 1976-1980 457M05100
WISECO
$152.95If you're running a YZ 80 and want genuine performance gains, a quality piston kit is where it starts. The Wiseco 520M05000 delivers measurable improvements in throttle response and engine...520M05000- SKU:
- 520M05000
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- BORE - OVERSIZE:
- +2,00 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 45,60 MM
- UNITS:
- EACH
- BORE SIZE METRIC:
- 50.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH METRIC:
- 45.60 MM
- DISPLACEMENT:
- 82 CC
- BORE - OVERSIZE METRIC:
- +2.00 MM
- RIDING STYLE:
- OFF-ROAD
$152.95 -
Wiseco Cam Chain 2003-2005 Honda CRF150F CC012
WISECO
$66.95A worn or inadequate cam chain can cause timing slippage, reduced valve lift, and premature engine wear—compromising both reliability and performance. The Wiseco CC012 is engineered to eliminate...09250312- SKU:
- 09250312
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- NUMBER OF LINKS:
- 100
- PRODUCT NAME:
- CHAIN
- TYPE:
- CAM
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- CHAIN SIZE:
- 92RH2005
$66.95 -
Wiseco 74mm Piston Ring Set for Honda TRX250X 1987-1988 1991-1992 2913XC
WISECO
$52.95Factory piston rings wear out under racing loads, causing blow-by, power loss, and accelerated engine wear. The Wiseco 2913XC ring set restores proper cylinder sealing and compression, delivering the...2913XC- SKU:
- 2913XC
- Availability:
- Ships Same Business Day
- Weight:
- 0.13 LBS
- DISPLACEMENT:
- 246 CC
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- PISTON RING
- UNITS:
- SET
- DISPLACEMENT:
- 282 CC
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 74.00 MM
$52.95 -
Wiseco Piston Kit 68.50mm for Honda CR250R 1997-2001 PK1172
WISECO
$297.95When your CR250R's top end reaches the end of its service life, a quality rebuild kit isn't optional—it's essential to maintaining the power and reliability your bike demands. The Wiseco PK1172...09030523- SKU:
- 09030523
- Availability:
- Ships Same Business Day
- Weight:
- 1.25 LBS
- BORE - OVERSIZE METRIC:
- +2.10 MM
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- PRO-LITE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
- BORE SIZE METRIC:
- 68.50 MM
- PISTON DIAMETER METRIC:
- 68.46 MM
- PRODUCT NAME:
- REBUILD KIT
- STROKE LENGTH METRIC:
- 72.00 MM
- BORE - OVERSIZE:
- +2,10 MM
- SKIRT COATING:
- NON-COATED
- DISPLACEMENT:
- 249 CC
$297.95 -
Wiseco Piston Kit 76mm 12.8:1 Compression for 2006-2012 KTM 250 SX-F 4981M07600
WISECO
$266.95Wiseco's 4981M07600 piston kit delivers the compression ratio and bore precision your KTM 250 SX-F demands for serious trail and motocross performance. The aerospace-grade forged aluminum...09100846- SKU:
- 09100846
- Availability:
- Ships Same Business Day
- Weight:
- 0.57 LBS
- BORE SIZE METRIC:
- 76.00 MM
- RIDING STYLE:
- STREET
- DISPLACEMENT:
- 249,5 CC
- SKIRT COATING:
- MOLY COATED
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 12.8:1
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
$266.95 -
Wiseco Piston Kit 78mm 13.5:1 Honda CRF250R 2004-2007 CRF250X 2004-2017 PK1240
WISECO
$362.95If you're running a CRF250R or CRF250X and want measurable gains in power output and engine durability, a quality piston kit is non-negotiable. The Wiseco PK1240 delivers the compression ratio and...09030551- SKU:
- 09030551
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- DISPLACEMENT:
- 249 CC
- BORE SIZE METRIC:
- 78.00 MM
- PRODUCT NAME:
- REBUILD KIT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- MODEL:
- FORGED SERIES
- SKIRT COATING:
- ARMORGLIDE®
- STROKE LENGTH METRIC:
- 52.20 MM
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- PISTON DIAMETER METRIC:
- 77.95 MM
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
$362.95 -
Wiseco Piston Kit with Gaskets for Kawasaki KX450F 2006-2008 PK1403
WISECO
$328.95When your KX450F's top end starts showing wear, a quality piston kit is the foundation of reliable power restoration. Wiseco's PK1403 delivers the precision engineering and durable materials you need...09030575- SKU:
- 09030575
- Availability:
- Ships Same Business Day
- Weight:
- 1.70 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 96.00 MM
- DISPLACEMENT:
- 449 CC
- PISTON DIAMETER METRIC:
- STANDARD
- SKIRT COATING:
- ARMORGLIDE®
- BORE - OVERSIZE:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 12.0:1
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- FORGED SERIES
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- PRODUCT NAME:
- REBUILD KIT
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 62.10 MM
- TYPE:
- TOP END
- UNITS:
- KIT
$328.95 -
On Sale
Wossner Connecting Rod for Honda CRF450R 2002-2008 P4026
WOSSNER
MSRP: $174.00Now: $165.30Was: $174.00If you're rebuilding a CRF450R engine, the connecting rod is your foundation for reliable power delivery and longevity. Wössner's 8620 forged construction and shot-peening process deliver the fatigue...09230441- SKU:
- 09230441
- Availability:
- Ships Same Business Day
- Weight:
- 1.65 LBS
- PRODUCT NAME:
- CONNECTING ROD KIT
- STYLE:
- STANDARD
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $174.00Now: $165.30Was: $174.00 -
On Sale
Wossner Connecting Rod Honda CRF450R 2009-2016 P4027
WOSSNER
MSRP: $174.00Now: $165.30Was: $174.00A connecting rod is the critical link between your piston and crankshaft—when it fails, your engine fails. The Wössner P4027 is engineered from 8620 forged alloy with shot peening and FEA...09230442- SKU:
- 09230442
- Availability:
- Ships Same Business Day
- Weight:
- 1.60 LBS
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- CONNECTING ROD KIT
- STYLE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $174.00Now: $165.30Was: $174.00 -
On Sale
Wossner Connecting Rod for KTM 250 EXC 2001-2006 P4048
WOSSNER
MSRP: $174.00Now: $165.30Was: $174.00If you're rebuilding the top end of your KTM 250 EXC, the connecting rod is the critical link between piston and crankshaft—a weak point here will compromise both reliability and power delivery. The...09230450- SKU:
- 09230450
- Availability:
- Ships Same Business Day
- Weight:
- 2.05 LBS
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- CONNECTING ROD KIT
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- STANDARD
- UNITS:
- KIT
MSRP: $174.00Now: $165.30Was: $174.00 -
On Sale
Wossner Piston Kit KTM 250 SX-F 2016-2022 8923DB
WOSSNER
MSRP: $224.00Now: $212.80Was: $224.00Whether you're prepping for race season or rebuilding after a hard season of riding, a quality piston kit is non-negotiable for 2-stroke performance. The Wössner 8923DB delivers the durability and...09106135- SKU:
- 09106135
- Availability:
- Ships Same Business Day
- Weight:
- 0.22 LBS
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 78.01 MM
- COMPRESSION RATIO IMPERIAL:
- 14.4:1
- BORE - OVERSIZE:
- +0,01 MM
- BORE - OVERSIZE METRIC:
- +0.01 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- PREMIUM SERIES
- PISTON SIZE METRIC:
- 77.97 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $224.00Now: $212.80Was: $224.00 -
MOOSE RACING Crank Bearing - KDX/JR50 24-1067
MOOSE RACING
$43.95A worn or failing crankshaft bearing is the fastest way to turn a running 2-stroke into a seized engine. This MOOSE RACING precision bearing kit restores proper crankshaft support and sealing,...09240102- SKU:
- 09240102
- Availability:
- Ships Same Business Day
- Weight:
- 0.39 LBS
- PRODUCT NAME:
- BEARING
- RIDING STYLE:
- ATV
- TYPE:
- BALL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- CRANKSHAFT
- RIDING STYLE:
- STREET
$43.95 -
On Sale
PROX Exhaust Valve 28.1227-1
PROX
MSRP: $30.95Now: $25.00Was: $30.95A precision exhaust valve is critical to maintaining proper combustion chamber sealing and engine performance under high RPM and sustained heat cycles. OEM-specification exhaust valves like the PROX...09260668- SKU:
- 09260668
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- UNITS:
- EACH
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- VALVE
MSRP: $30.95Now: $25.00Was: $30.95 -
PROX Intake Valve and Spring Kit 28.SIS3338-2
PROX
$155.95If you're pushing your engine to the limit, OEM valve springs will eventually let you down—they simply aren't engineered for sustained high-RPM loads. The PROX Intake Valve and Spring Kit 28...09261461- SKU:
- 09261461
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- SPRING KIT
- TYPE:
- VALVE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- TI-STEEL
$155.95 -
PROX Valve and Spring Kit 28.SIS4341-2
PROX
$155.95If you're running your engine hard at high RPM, OEM valve and spring components become a limiting factor—they simply weren't engineered to handle sustained extreme conditions. The PROX 28.SIS4341-2...09261465- SKU:
- 09261465
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- SPRING KIT
- TYPE:
- VALVE
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$155.95 -
PROX Water Pump Rebuild Kit - Honda 57.1422
PROX
$36.95A failing water pump can compromise cooling system integrity and lead to catastrophic engine damage. The PROX Water Pump Rebuild Kit restores OEM performance with precision-engineered components,...09346993- SKU:
- 09346993
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- PRODUCT NAME:
- REPAIR KIT
- TYPE:
- WATER PUMP
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$36.95 -
PROX Water Pump Rebuild Kit - Kawasaki 57.4317
PROX
$41.95A failing water pump compromises engine cooling efficiency and risks catastrophic overheating during high-stress riding or racing conditions. The PROX Water Pump Rebuild Kit restores OEM-level...09347049- SKU:
- 09347049
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- PRODUCT NAME:
- REPAIR KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- WATER PUMP
$41.95
