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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On Sale
Wossner Honda CR250R 1986-1996 Piston Kit 8021DB
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00A worn or damaged piston directly compromises engine compression, throttle response, and overall reliability—especially critical in 2-stroke engines where piston quality defines performance. The...09104728- SKU:
- 09104728
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- BORE SIZE METRIC:
- 66.41 MM
- DISPLACEMENT:
- 249 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
- BORE - OVERSIZE:
- +0,01 MM
- BORE - OVERSIZE METRIC:
- +0.01 MM
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 66.35 MM
MSRP: $152.00Now: $144.40Was: $152.00Qty in Cart: 0Quantity:Price:MSRP: $152.00Now: $144.40Was: $152.00Subtotal: -
On Sale
Wossner Piston Kit Honda CR250R 1986-1996 8021DC
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00If you're running a CR250R at the track or trail, piston longevity and ring seal integrity directly impact your lap times and engine reliability. The Wossner 8021DC delivers the durability and...09104729- SKU:
- 09104729
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- BORE SIZE METRIC:
- 66.42 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- TYPE:
- DUAL RING
- DISPLACEMENT:
- 249 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE METRIC:
- +0.02 MM
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE:
- +0,02 MM
- PISTON SIZE METRIC:
- 66.36 MM
MSRP: $152.00Now: $144.40Was: $152.00Qty in Cart: 0Quantity:Price:MSRP: $152.00Now: $144.40Was: $152.00Subtotal: -
On Sale
Wossner Piston Kit 66.95mm 1989-1995 Suzuki RM250 8022DB
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00When you're pushing an RM250 to its limits, piston durability and ring seal become non-negotiable. The Wossner 8022DB delivers the thermal stability and precision fit that 2-stroke performance...09104732- SKU:
- 09104732
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- BORE - OVERSIZE:
- +0,01 MM
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
- BORE SIZE METRIC:
- 67.01 MM
- DISPLACEMENT:
- 246 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE METRIC:
- +0.01 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON SIZE METRIC:
- 66.95 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $152.00Now: $144.40Was: $152.00Qty in Cart: 0Quantity:Price:MSRP: $152.00Now: $144.40Was: $152.00Subtotal: -
On Sale
Wossner Piston Kit 53.95mm 2000-2003 Suzuki RM125 8061DA
WOSSNER
MSRP: $122.00Now: $115.90Was: $122.00If you're running a 2000-2003 Suzuki RM125, a quality piston kit is essential to maintaining peak performance and engine reliability. The Wossner 8061DA delivers the durability and precision...09104770- SKU:
- 09104770
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 124 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- SINGLE RING
- UNITS:
- KIT
- PISTON SIZE METRIC:
- 53.95 MM
- BORE - OVERSIZE:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
MSRP: $122.00Now: $115.90Was: $122.00Qty in Cart: 0Quantity:Price:MSRP: $122.00Now: $115.90Was: $122.00Subtotal: -
On Sale
Wossner Piston Kit 53.96mm for 2000-2003 Suzuki RM125 8061DB
WOSSNER
MSRP: $122.00Now: $115.90Was: $122.00If you're rebuilding a 2000-2003 RM125 or pushing your 2-stroke to its limits, a quality piston kit is non-negotiable for reliability and peak performance. The Wössner 8061DB delivers the precision...09104771- SKU:
- 09104771
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE - OVERSIZE METRIC:
- +0.01 MM
- BORE SIZE METRIC:
- 54.01 MM
- DISPLACEMENT:
- 124 CC
- TYPE:
- SINGLE RING
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- 53.96 MM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- +0,01 MM
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- PISTON MATERIAL:
- FORGED
MSRP: $122.00Now: $115.90Was: $122.00Qty in Cart: 0Quantity:Price:MSRP: $122.00Now: $115.90Was: $122.00Subtotal: -
On Sale
Wossner Honda CR250R 2002-2004 Piston Kit 8066DA
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00If you're running a 2002-2004 Honda CR250R, a worn or damaged piston directly kills your engine's efficiency, compression, and throttle response. The Wössner 8066DA delivers the reliability and...09104773- SKU:
- 09104773
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- BORE SIZE METRIC:
- 66.40 MM
- ENGINE TYPE:
- 2-STROKE
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- MODEL:
- STANDARD SERIES
- PISTON SIZE METRIC:
- 66.34 MM
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- FORGED
- TYPE:
- DUAL RING
MSRP: $152.00Now: $144.40Was: $152.00 -
On Sale
Wossner Piston Kit 66.35mm Honda CR250R 2002-2004 8066DB
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00If you're running a CR250R between 2002–2004, piston wear directly impacts power delivery, throttle response, and engine longevity. The Wossner 8066DB kit replaces worn components with...09104774- SKU:
- 09104774
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- UNITS:
- KIT
- BORE - OVERSIZE:
- +0,01 MM
- BORE - OVERSIZE METRIC:
- +0.01 MM
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 66.41 MM
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 66.35 MM
- TYPE:
- DUAL RING
MSRP: $152.00Now: $144.40Was: $152.00Qty in Cart: 0Quantity:Price:MSRP: $152.00Now: $144.40Was: $152.00Subtotal: -
On Sale
Wossner Piston Kit 54.45mm for Honda CR125R 1992-2003 8067D050
WOSSNER
MSRP: $142.00Now: $134.90Was: $142.00The Wossner 8067D050 piston kit delivers the reliability and precision that serious CR125R riders demand, whether you're prepping for competition or maintaining peak performance in your 2-stroke...09104775- SKU:
- 09104775
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE SIZE METRIC:
- 54.50 MM
- PISTON SIZE METRIC:
- 54.45 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- DISPLACEMENT:
- 125 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- SINGLE RING
- BORE - OVERSIZE:
- +0,50 MM
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
MSRP: $142.00Now: $134.90Was: $142.00Qty in Cart: 0Quantity:Price:MSRP: $142.00Now: $134.90Was: $142.00Subtotal: -
On Sale
Wossner 53.95mm Piston Kit for Honda CR125R 2000-2003 8067DA
WOSSNER
MSRP: $142.00Now: $134.90Was: $142.00Two-stroke engines demand pistons engineered for extreme conditions, and the Wossner 8067DA delivers the precision and durability required for competitive riding and racing. This complete kit...09104778- SKU:
- 09104778
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 125 CC
- PISTON SIZE METRIC:
- 53.95 MM
- TYPE:
- SINGLE RING
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
MSRP: $142.00Now: $134.90Was: $142.00Qty in Cart: 0Quantity:Price:MSRP: $142.00Now: $134.90Was: $142.00Subtotal: -
On Sale
Wossner 53.97mm Piston Kit for 2000-2003 Honda CR125R 8067DC
WOSSNER
MSRP: $142.00Now: $134.90Was: $142.00When you're pushing a CR125R to its limits, your piston needs to survive the punishment—and deliver consistent power lap after lap. The Wossner 8067DC combines German engineering with purpose-built...09104780- SKU:
- 09104780
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- DISPLACEMENT:
- 125 CC
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- +0,02 MM
- BORE - OVERSIZE METRIC:
- +0.02 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 53.97 MM
- BORE SIZE METRIC:
- 54.02 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- SINGLE RING
- UNITS:
- KIT
MSRP: $142.00Now: $134.90Was: $142.00Qty in Cart: 0Quantity:Price:MSRP: $142.00Now: $134.90Was: $142.00Subtotal: -
On Sale
Wossner Yamaha YZ125 2002-2004 53.96mm Piston Kit 8072DC
WOSSNER
MSRP: $122.00Now: $115.90Was: $122.00If you're running a YZ125 between 2002-2004, piston wear is inevitable—and when it happens, you need a direct replacement that matches OEM specifications without compromise. The Wössner 8072DC...09104789- SKU:
- 09104789
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE SIZE METRIC:
- 54.02 MM
- DISPLACEMENT:
- 124 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- SINGLE RING
- UNITS:
- KIT
- BORE - OVERSIZE:
- +0,02 MM
- BORE - OVERSIZE METRIC:
- +0.02 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 53.96 MM
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
MSRP: $122.00Now: $115.90Was: $122.00Qty in Cart: 0Quantity:Price:MSRP: $122.00Now: $115.90Was: $122.00Subtotal: -
On Sale
Wossner Piston Kit Honda CR125R 2005-2007 8170DB
WOSSNER
MSRP: $122.00Now: $115.90Was: $122.00The Wössner 8170DB piston kit is engineered for riders who demand reliability and consistent performance from their 2-stroke CR125R. This complete assembly eliminates the guesswork of sourcing...09104865- SKU:
- 09104865
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- BORE - OVERSIZE METRIC:
- +0.01 MM
- BORE SIZE METRIC:
- 54.01 MM
- TYPE:
- SINGLE RING
- UNITS:
- KIT
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- PISTON SIZE METRIC:
- 53.96 MM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- +0,01 MM
- DISPLACEMENT:
- 125 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
MSRP: $122.00Now: $115.90Was: $122.00Qty in Cart: 0Quantity:Price:MSRP: $122.00Now: $115.90Was: $122.00Subtotal: -
On Sale
Wossner Piston Kit KTM 125 2007-2025 54.02mm 8174DC
WOSSNER
MSRP: $122.00Now: $115.90Was: $122.00When you're pushing a KTM 125 to its limits, your piston is your most critical wear component. The Wossner 8174DC delivers the durability and thermal stability needed to survive intense 2-stroke...09104871- SKU:
- 09104871
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- 53.97 MM
- RIDING STYLE:
- OFF-ROAD
- DISPLACEMENT:
- 125 CC
- TYPE:
- DUAL RING
- BORE - OVERSIZE:
- +0,02 MM
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +0.02 MM
- BORE SIZE METRIC:
- 54.02 MM
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
MSRP: $122.00Now: $115.90Was: $122.00Qty in Cart: 0Quantity:Price:MSRP: $122.00Now: $115.90Was: $122.00Subtotal: -
On Sale
Wossner Piston Kit 71.94mm 2014-2016 Husqvarna TE300 8250DA
WOSSNER
MSRP: $192.00Now: $182.40Was: $192.00The TE300's stock piston won't cut it if you're pushing higher RPMs or running extended sessions in demanding terrain. Wossner's 8250DA kit delivers the durability and thermal stability a 2-stroke...09104895- SKU:
- 09104895
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- BORE SIZE METRIC:
- 72.00 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 293 CC
- PISTON SIZE METRIC:
- 71.94 MM
MSRP: $192.00Now: $182.40Was: $192.00Qty in Cart: 0Quantity:Price:MSRP: $192.00Now: $182.40Was: $192.00Subtotal: -
XCELDYNE Valve Locks XLOM55750
XCELDYNE
$38.18Valve locks are critical to high-RPM engine stability—without secure keepers, you risk catastrophic valve failure and potential engine damage. The XCELDYNE XLOM55750 addresses this with...09260524- SKU:
- 09260524
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- MATERIAL:
- STEEL
- PRODUCT NAME:
- LOCK
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
- APPLICATION:
- INTAKE
- RIDING STYLE:
- ATV
- UNITS:
- SET OF 4
$38.18Qty in Cart: 0Quantity:Price:$38.18Subtotal: -
XCELDYNE Valve Locks XLOM55751
XCELDYNE
$38.18Valve locks are critical to engine reliability at high RPM, and failure means catastrophic internal damage. XCELDYNE's purpose-built design keeps your valvetrain secure where inferior locks fail,...09260525- SKU:
- 09260525
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- APPLICATION:
- EXHAUST
- UNITS:
- SET OF 4
- MATERIAL:
- STEEL
- PRODUCT NAME:
- LOCK
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
$38.18Qty in Cart: 0Quantity:Price:$38.18Subtotal: -
On Sale
ATHENA Top End Gasket Kit - Yamaha P400485600213
ATHENA
MSRP: $61.95Now: $56.00Was: $61.95A top-end gasket kit is essential maintenance for any racer looking to maximize engine reliability between rebuilds. The ATHENA P400485600213 gives you the flexibility to run either pump gas with...09346470- SKU:
- 09346470
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- TOP END
MSRP: $61.95Now: $56.00Was: $61.95Qty in Cart: 0Quantity:Price:MSRP: $61.95Now: $56.00Was: $61.95Subtotal: -
On Sale
ATHENA Water Pump Gasket Kit - Honda P400210475008
ATHENA
MSRP: $29.95Now: $25.00Was: $29.95Proper coolant sealing is non-negotiable in high-performance applications—a failed water pump gasket can lead to catastrophic overheating and engine damage. The ATHENA Water Pump Gasket Kit delivers...09346044- SKU:
- 09346044
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- WATER PUMP
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $29.95Now: $25.00Was: $29.95 -
On Sale
ATHENA Water Pump Gasket Kit - Suzuki P400510475001
ATHENA
MSRP: $34.95Now: $31.00Was: $34.95Include water pump gasket, clutch cover gasket, water pump shaft oil seals and washers, Kit contents will vary slightly based on application, Kits do not contain replacement bearings09346080- SKU:
- 09346080
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- TYPE:
- WATER PUMP
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- GASKET KIT
MSRP: $34.95Now: $31.00Was: $34.95Qty in Cart: 0Quantity:Price:MSRP: $34.95Now: $31.00Was: $34.95Subtotal: -
On Sale
ATHENA Water Pump Gasket Kit - Yamaha P400485475007
ATHENA
MSRP: $39.95Now: $34.00Was: $39.95Include water pump gasket, clutch cover gasket, water pump shaft oil seals and washers, Kit contents will vary slightly based on application, Kits do not contain replacement bearings09346089- SKU:
- 09346089
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
MSRP: $39.95Now: $34.00Was: $39.95Qty in Cart: 0Quantity:Price:MSRP: $39.95Now: $34.00Was: $39.95Subtotal:
