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
-
On Sale
Wossner Top End Bearing for Kawasaki KX85 2001-2013 N1007
WOSSNER
MSRP: $18.50Now: $17.58Was: $18.50The Wossner Top End Bearing is a critical wear item for KX85 two-stroke engines operating at high RPM. When the original bearing begins to show play or noise, replacement is essential to prevent...09240448- SKU:
- 09240448
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- LENGTH METRIC:
- 17.2 MM
- OUTSIDE DIAMETER METRIC:
- 18 MM
- TYPE:
- TOP END
- UNITS:
- EACH
- APPLICATION:
- CONNECTING ROD
- RIDING STYLE:
- OFF-ROAD
- INSIDE DIAMETER METRIC:
- 18 MM
- PRODUCT NAME:
- BEARING
MSRP: $18.50Now: $17.58Was: $18.50Qty in Cart: 0Quantity:Price:MSRP: $18.50Now: $17.58Was: $18.50Subtotal: -
On Sale
Wossner Top End Bearing 15x19x19.5 mm for 2007-2014 KTM 125 SX N1010
WOSSNER
MSRP: $18.50Now: $17.58Was: $18.50The top end bearing is critical to your KTM 125 SX's reliability—a worn or damaged bearing will compromise piston rod movement and accelerate wear across your entire top end. This Wossner bearing is...09240450- SKU:
- 09240450
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OUTSIDE DIAMETER METRIC:
- 19 MM
- APPLICATION:
- CONNECTING ROD
- RIDING STYLE:
- OFF-ROAD
- INSIDE DIAMETER METRIC:
- 15 MM
- LENGTH METRIC:
- 19.5 MM
- RIDING STYLE:
- STREET
- TYPE:
- TOP END
- UNITS:
- EACH
- PRODUCT NAME:
- BEARING
MSRP: $18.50Now: $17.58Was: $18.50 -
On Sale
Wossner Top End Bearing 18 mm x 22 mm x 19.8 mm N1020
WOSSNER
MSRP: $18.50Now: $17.58Was: $18.50A worn or inadequate top end bearing is a direct path to increased friction, premature wear, and catastrophic engine failure. The Wossner N1020 delivers precision-engineered reliability in a compact...09240456- SKU:
- 09240456
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- LENGTH METRIC:
- 19.8 MM
- OUTSIDE DIAMETER METRIC:
- 22 MM
- APPLICATION:
- CONNECTING ROD
- INSIDE DIAMETER METRIC:
- 18 MM
- RIDING STYLE:
- STREET
- UNITS:
- EACH
- PRODUCT NAME:
- BEARING
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
MSRP: $18.50Now: $17.58Was: $18.50Qty in Cart: 0Quantity:Price:MSRP: $18.50Now: $17.58Was: $18.50Subtotal: -
On Sale
Wossner Top End Bearing 18x22x21.8mm Honda CR250R N1021
WOSSNER
MSRP: $18.50Now: $17.58Was: $18.50Top-end bearing wear is one of the fastest paths to catastrophic engine failure—especially under the high RPMs and thermal stress of racing. The Wössner N1021 is a precision needle roller bearing...09240457- SKU:
- 09240457
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- INSIDE DIAMETER METRIC:
- 18 MM
- PRODUCT NAME:
- BEARING
- UNITS:
- EACH
- APPLICATION:
- CONNECTING ROD
- OUTSIDE DIAMETER METRIC:
- 22 MM
- LENGTH METRIC:
- 21.8 MM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
MSRP: $18.50Now: $17.58Was: $18.50 -
On Sale
Wossner Top End Bearing 18x23x21.8mm Suzuki RM250 1977-2008 N1022
WOSSNER
MSRP: $18.50Now: $17.58Was: $18.50Top end bearings are critical wear items in two-stroke engines—they directly impact crankshaft stability, reduce parasitic friction losses, and extend engine longevity under high RPM loads. The...09240458- SKU:
- 09240458
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- INSIDE DIAMETER METRIC:
- 18 MM
- TYPE:
- TOP END
- LENGTH METRIC:
- 21.8 MM
- OUTSIDE DIAMETER METRIC:
- 23 MM
- PRODUCT NAME:
- BEARING
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- CONNECTING ROD
- UNITS:
- EACH
MSRP: $18.50Now: $17.58Was: $18.50 -
On Sale
Wossner Top End Bearing for Kawasaki KX65 2000-2022 N1036
WOSSNER
MSRP: $18.50Now: $17.58Was: $18.50The top end bearing is a critical wear item in high-revving two-stroke engines—it bears the brunt of crankshaft loads and demands precision engineering to prevent catastrophic failure. The Wossner...09240459- SKU:
- 09240459
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OUTSIDE DIAMETER METRIC:
- 16 MM
- PRODUCT NAME:
- BEARING
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- EACH
- APPLICATION:
- CONNECTING ROD
- INSIDE DIAMETER METRIC:
- 12 MM
- LENGTH METRIC:
- 15.8 MM
MSRP: $18.50Now: $17.58Was: $18.50 -
On Sale
Wossner Suzuki RM250 1998 Piston Kit 66.34mm 8140DA
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00If you're rebuilding a 1998 Suzuki RM250 2-stroke, piston quality directly impacts throttle response, engine longevity, and overall reliability. The Wossner 8140DA delivers OEM-spec fitment with...09105552- SKU:
- 09105552
- Availability:
- Ships Same Business Day
- Weight:
- 0.76 LBS
- BORE SIZE METRIC:
- 66.40 MM
- DISPLACEMENT:
- 246 CC
- PISTON SIZE METRIC:
- 66.34 MM
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
- BORE - OVERSIZE:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
MSRP: $152.00Now: $144.40Was: $152.00Qty in Cart: 0Quantity:Price:MSRP: $152.00Now: $144.40Was: $152.00Subtotal: -
On Sale
Wossner Piston Kit 55.44mm Honda CR125R 1980-1984 8149DA
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00When you're rebuilding a classic CR125R or pushing your 2-stroke engine to its limits, piston quality directly impacts reliability and peak performance. The Wossner 8149DA delivers the precision...09105553- SKU:
- 09105553
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- FORGED
- TYPE:
- DUAL RING
- DISPLACEMENT:
- 124 CC
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 55.50 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- PISTON SIZE METRIC:
- 55.44 MM
- UNITS:
- KIT
MSRP: $132.00Now: $125.40Was: $132.00Qty in Cart: 0Quantity:Price:MSRP: $132.00Now: $125.40Was: $132.00Subtotal: -
On Sale
Wossner Piston Kit Honda CR250R 1984-1985 8156DA
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00The Wossner 8156DA piston kit is engineered to restore or exceed your CR250R's original performance capabilities while delivering the durability needed for sustained high-RPM operation. Factory...09105555- SKU:
- 09105555
- Availability:
- Ships Same Business Day
- Weight:
- 0.71 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 66.00 MM
- DISPLACEMENT:
- 250 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 65.94 MM
- RIDING STYLE:
- ATV
- ENGINE TYPE:
- 2-STROKE
- 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 Honda CR250R 1984-1985 Piston Kit 8156D025
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00The Wossner 8156D025 piston kit delivers the precision engineering and durability required for sustained high-RPM performance in your Honda CR250R. This complete kit eliminates guesswork with matched...09105556- SKU:
- 09105556
- Availability:
- Ships Same Business Day
- Weight:
- 0.71 LBS
- BORE - OVERSIZE:
- +0,25 MM
- BORE - OVERSIZE METRIC:
- +0.25 MM
- BORE SIZE METRIC:
- 66.25 MM
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 66.19 MM
- TYPE:
- DUAL RING
- DISPLACEMENT:
- 250 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- ATV
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- 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 66.50 mm for Honda CR250R 1997-2001 8156D050
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00When you're rebuilding a CR250R engine, piston quality directly impacts throttle response, reliability, and how long your engine stays in the game. The Wossner 8156D050 delivers the precision...09105557- SKU:
- 09105557
- Availability:
- Ships Same Business Day
- Weight:
- 0.76 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- +0,50 MM
- DISPLACEMENT:
- 250 CC
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 66.50 MM
- TYPE:
- DUAL RING
- MODEL:
- STANDARD SERIES
- PISTON SIZE METRIC:
- 66.44 MM
- PRODUCT NAME:
- PISTON KIT
MSRP: $152.00Now: $144.40Was: $152.00 -
On Sale
Wossner Piston Kit 66.69mm Honda CR250R 1984-1985 8156D075
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00Stock pistons are a wear item in 2-stroke engines, and when yours fails, you lose compression, power, and reliability. The Wossner 8156D075 restores your CR250R to peak performance with a...09105558- SKU:
- 09105558
- Availability:
- Ships Same Business Day
- Weight:
- 0.71 LBS
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 66.75 MM
- BORE - OVERSIZE:
- +0,75 MM
- DISPLACEMENT:
- 250 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 66.69 MM
- BORE - OVERSIZE METRIC:
- +0.75 MM
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
MSRP: $152.00Now: $144.40Was: $152.00Qty in Cart: 0Quantity:Price:MSRP: $152.00Now: $144.40Was: $152.00Subtotal: -
On Sale
Wossner Honda CR250R 1997-2001 Piston Kit 8161DB
WOSSNER
MSRP: $150.96Now: $143.41Was: $150.96The Wossner 8161DB piston kit delivers the precision engineering your 2-stroke CR250R demands for consistent power delivery and extended engine life. Purpose-built with German forging expertise and...09105564- SKU:
- 09105564
- Availability:
- Ships Same Business Day
- Weight:
- 0.66 LBS
- BORE - OVERSIZE METRIC:
- +0.01 MM
- TYPE:
- SINGLE RING
- UNITS:
- KIT
- DISPLACEMENT:
- 249 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- +0,01 MM
- BORE SIZE METRIC:
- 66.41 MM
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 66.35 MM
MSRP: $150.96Now: $143.41Was: $150.96Qty in Cart: 0Quantity:Price:MSRP: $150.96Now: $143.41Was: $150.96Subtotal: -
On Sale
Wossner Piston Kit for Honda CR250R 1997-2001 8161DC
WOSSNER
MSRP: $150.96Now: $143.41Was: $150.96Your CR250R's performance is only as strong as its core. Wossner's 8161DC piston kit delivers the thermal stability and reduced friction your 2-stroke engine demands during aggressive riding, whether...09105565- SKU:
- 09105565
- Availability:
- Ships Same Business Day
- Weight:
- 0.71 LBS
- BORE - OVERSIZE METRIC:
- +0.02 MM
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- +0,02 MM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 249 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON SIZE METRIC:
- 66.36 MM
- TYPE:
- SINGLE RING
- BORE SIZE METRIC:
- 66.42 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
MSRP: $150.96Now: $143.41Was: $150.96Qty in Cart: 0Quantity:Price:MSRP: $150.96Now: $143.41Was: $150.96Subtotal: -
On Sale
Wossner Piston Kit Kawasaki KX250 2005-2007 8168DB
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00When you're pushing a KX250 to its limits, factory pistons won't cut it. The Wossner 8168DB delivers the strength, heat resistance, and precision engineering you need to maintain peak performance lap...09105566- SKU:
- 09105566
- Availability:
- Ships Same Business Day
- Weight:
- 0.71 LBS
- BORE - OVERSIZE METRIC:
- +0.01 MM
- BORE SIZE METRIC:
- 66.41 MM
- DISPLACEMENT:
- 249 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE:
- +0,01 MM
- 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 Yamaha IT250 1983 8175D100
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00If you're rebuilding a 1983 Yamaha IT250 or pushing this classic 2-stroke to its limits, piston quality directly impacts reliability, power delivery, and engine longevity. The Wossner 8175D100 kit...09105568- SKU:
- 09105568
- Availability:
- Ships Same Business Day
- Weight:
- 0.76 LBS
- BORE - OVERSIZE:
- +1,00 MM
- DISPLACEMENT:
- 246 CC
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- TYPE:
- DUAL RING
- BORE - OVERSIZE METRIC:
- +1.00 MM
- BORE SIZE METRIC:
- 69.00 MM
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 68.94 MM
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
MSRP: $152.00Now: $144.40Was: $152.00Qty in Cart: 0Quantity:Price:MSRP: $152.00Now: $144.40Was: $152.00Subtotal: -
On Sale
Wossner Piston Kit 70.44mm Yamaha IT250 1978-1980 YZ250 1976-1979 8179D050
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00When you're pushing a 2-stroke to its limits, stock pistons become your bottleneck. The Wossner 8179D050 kit delivers the strength and precision engineering needed to handle aggressive riding, high...09105570- SKU:
- 09105570
- Availability:
- Ships Same Business Day
- Weight:
- 0.76 LBS
- DISPLACEMENT:
- 246 CC
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- BORE - OVERSIZE:
- +0,50 MM
- BORE SIZE METRIC:
- 70.50 MM
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +0.50 MM
- TYPE:
- DUAL RING
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- 70.44 MM
- RIDING STYLE:
- OFF-ROAD
MSRP: $152.00Now: $144.40Was: $152.00 -
On Sale
Wossner Piston Kit Yamaha YZ250 1976-1979 72mm 8179D200
WOSSNER
MSRP: $182.00Now: $172.90Was: $182.00The Wossner Piston Kit 8179D200 is engineered specifically for Yamaha YZ250 models from 1976-1979, delivering the precision and durability your 2-stroke demands during aggressive riding conditions...09105571- SKU:
- 09105571
- Availability:
- Ships Same Business Day
- Weight:
- 0.81 LBS
- DISPLACEMENT:
- 246 CC
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- TYPE:
- DUAL RING
- BORE - OVERSIZE:
- +2,00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 71.94 MM
- BORE - OVERSIZE METRIC:
- +2.00 MM
- BORE SIZE METRIC:
- 72.00 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $182.00Now: $172.90Was: $182.00 -
On Sale
Wossner Piston Kit Kawasaki KX80 1988-2000 47.95mm 8197DA
WOSSNER
MSRP: $112.00Now: $106.40Was: $112.00Your KX80's longevity depends on a piston that can handle the demands of 2-stroke performance without sacrificing reliability. The Wossner 8197DA delivers the durability and precision engineering...09105572- SKU:
- 09105572
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 47.95 MM
- BORE SIZE METRIC:
- 48.00 MM
- DISPLACEMENT:
- 79 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- SINGLE RING
- UNITS:
- KIT
MSRP: $112.00Now: $106.40Was: $112.00Qty in Cart: 0Quantity:Price:MSRP: $112.00Now: $106.40Was: $112.00Subtotal: -
On Sale
Wossner Piston Kit 57.95mm for 2016-2022 KTM 150 SX 8299DA
WOSSNER
MSRP: $142.00Now: $134.90Was: $142.00A worn or stock piston compromises your 150 SX's power delivery and longevity, especially under sustained high-RPM racing loads. The Wossner 8299DA delivers the durability and precision your engine...09105589- SKU:
- 09105589
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PRODUCT NAME:
- PISTON KIT
- DISPLACEMENT:
- 143 CC
- MODEL:
- STANDARD SERIES
- BORE SIZE METRIC:
- 58.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 57.95 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:
