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
-
Wiseco Piston 2.00mm Oversize Honda CR125R 1987 676M05600
WISECO
$179.95When you're pushing a CR125R to its limits, stock pistons won't cut it. The Wiseco 2.00mm oversize piston delivers the reliability and compression you need to extract maximum power without sacrificing longevity. Built for serious racers who demand...676M05600- SKU:
- 676M05600
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- STROKE LENGTH:
- 54,50 MM
- DISPLACEMENT:
- 125 CC
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE:
- +2,00 MM
- BORE SIZE METRIC:
- 56.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- BORE - OVERSIZE METRIC:
- +2.00 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$179.95Qty in Cart: 0Quantity:Price:$179.95Subtotal: -
Wiseco Piston Standard Yamaha PW 50 1981-2020 653M04000
WISECO
$109.95Your PW 50's performance hinges on reliable internal components, and a quality piston is non-negotiable. The Wiseco 653M04000 delivers the durability and power output serious riders demand, whether you're putting in track time or tackling technical...653M04000- SKU:
- 653M04000
- Availability:
- Ships Same Business Day
- Weight:
- 0.24 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 40.00 MM
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 39,20 MM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 39.20 MM
- DISPLACEMENT:
- 49 CC
$109.95 -
WISECO Piston - Standard - Kawasaki KX 125 652M05400
WISECO
$162.95The Wiseco 652M05400 piston delivers the reliability and performance you need to keep your KX 125 competitive lap after lap. Built from high-silicon forged aluminum with a structurally advanced design, this piston handles the demands of both trail and...652M05400- SKU:
- 652M05400
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 54,50 MM
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE SIZE METRIC:
- 54.00 MM
- ENGINE TYPE:
- 2-STROKE
- BORE - OVERSIZE:
- STANDARD
- DISPLACEMENT:
- 124 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
$162.95Qty in Cart: 0Quantity:Price:$162.95Subtotal: -
Wiseco Piston Kit 53mm Bore Kawasaki KX100 1995-2013 Suzuki RM100 2003 651M05300
WISECO
$143.95If you're running a Kawasaki KX100 or Suzuki RM100, piston wear directly impacts throttle response, compression, and overall engine reliability. The Wiseco 651M05300 delivers a precision-engineered replacement that restores your engine's original...651M05300- SKU:
- 651M05300
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- STROKE LENGTH:
- 45,80 MM
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- STROKE LENGTH METRIC:
- 45.80 MM
- BORE SIZE METRIC:
- 53.00 MM
- DISPLACEMENT:
- 99 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- ENGINE TYPE:
- 2-STROKE
$143.95Qty in Cart: 0Quantity:Price:$143.95Subtotal: -
Wiseco Piston Kit 52.50mm Bore Kawasaki KX100 1995-2013 Suzuki RM100 2003 651M05250
WISECO
$143.95If you're running a KX100 or RM100 at the track or trail, piston wear directly impacts your power output and engine reliability. The Wiseco 651M05250 delivers a precision-engineered replacement that restores—or exceeds—OEM performance while improving...651M05250- SKU:
- 651M05250
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 52.50 MM
- DISPLACEMENT:
- 99 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 45,80 MM
- STROKE LENGTH METRIC:
- 45.80 MM
$143.95 -
Wiseco Piston Kit 48.00 mm Oversize for Yamaha PW80 2001-2006 649M04800
WISECO
$134.95If you're rebuilding a Yamaha PW80 or BW80 engine, a worn piston directly impacts throttle response, fuel efficiency, and overall reliability. The Wiseco 48.00mm oversize kit restores—or exceeds—factory performance by pairing high-silicon aluminum with...649M04800- SKU:
- 649M04800
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 42.00 MM
- UNITS:
- EACH
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 72 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 42,00 MM
- BORE SIZE METRIC:
- 48.00 MM
- BORE - OVERSIZE:
- +1,00 MM
- PRODUCT NAME:
- PISTON
$134.95Qty in Cart: 0Quantity:Price:$134.95Subtotal: -
Wiseco Piston 50mm Overbore Yamaha YZ125 2005-2025 647M05450
WISECO
$154.95Your YZ125's performance ceiling is limited by worn or stock pistons—and a quality replacement is the foundation of any serious build. The Wiseco 647M05450 delivers forged-aluminum durability and precision bore geometry that unlocks consistent power...647M05450- SKU:
- 647M05450
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE - OVERSIZE:
- +0,50 MM
- BORE SIZE METRIC:
- 54.50 MM
- DISPLACEMENT:
- 124 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- +0.50 MM
- STROKE LENGTH:
- 54,50 MM
- STROKE LENGTH METRIC:
- 54.50 MM
$154.95Qty in Cart: 0Quantity:Price:$154.95Subtotal: -
Wiseco Piston Standard Yamaha YZ125 1994-1996 647M05400
WISECO
$162.95If you're running a 1994-1996 Yamaha YZ125, piston wear directly impacts throttle response, compression, and overall engine reliability. A worn or damaged piston forces you to compensate with tuning adjustments and risks catastrophic engine failure...647M05400- SKU:
- 647M05400
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- DISPLACEMENT:
- 124 CC
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 54,50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE SIZE METRIC:
- 54.00 MM
$162.95Qty in Cart: 0Quantity:Price:$162.95Subtotal: -
Wiseco Piston Standard Yamaha YZ 80 1993-2001 646M04700
WISECO
$134.95The Wiseco 646M04700 piston is essential for YZ80 riders who demand reliable performance without compromise. Built from high-silicon forged aluminum, this piston delivers the strength needed for consistent power delivery across demanding riding...646M04700- SKU:
- 646M04700
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 47.00 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 47,80 MM
- RIDING STYLE:
- OFF-ROAD
- DISPLACEMENT:
- 82 CC
- STROKE LENGTH METRIC:
- 47.80 MM
$134.95Qty in Cart: 0Quantity:Price:$134.95Subtotal: -
Wiseco Piston Kit 48.50 mm for Kawasaki KX 80 1988-2000 644M04850
WISECO
$134.95Stock pistons can't handle the demands of extended trail riding or track time—especially in a high-revving two-stroke like the KX 80. This Wiseco piston kit delivers the durability and compression optimization your engine needs to maintain peak...644M04850- SKU:
- 644M04850
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- BORE - OVERSIZE METRIC:
- +0.50 MM
- DISPLACEMENT:
- 82 CC
- STROKE LENGTH:
- 45,80 MM
- STROKE LENGTH METRIC:
- 45.80 MM
- BORE - OVERSIZE:
- +0,50 MM
- BORE SIZE METRIC:
- 48.50 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$134.95Qty in Cart: 0Quantity:Price:$134.95Subtotal: -
Wiseco Piston Standard Kawasaki KX 80 1988-2000 644M04800
WISECO
$143.95A worn or stock piston limits your KX80's potential—restricting throttle response, reducing engine durability, and leaving power on the table. The Wiseco 644M04800 restores efficiency and longevity through precision engineering and premium materials,...644M04800- SKU:
- 644M04800
- Availability:
- Ships Same Business Day
- Weight:
- 0.34 LBS
- DISPLACEMENT:
- 82 CC
- ENGINE TYPE:
- 2-STROKE
- STROKE LENGTH:
- 45,80 MM
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 48.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 45.80 MM
$143.95 -
Wiseco Piston Kit 55.00 mm Kawasaki KX125 1993 626M05500
WISECO
$154.95If you're running a 1993 Kawasaki KX125, a worn piston directly kills your power delivery and throttle response. The Wiseco 626M05500 restores the compression and precision your engine needs to perform at peak efficiency, whether you're chasing lap times...626M05500- SKU:
- 626M05500
- Availability:
- Ships Same Business Day
- Weight:
- 0.44 LBS
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 55.00 MM
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 54.50 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 124 CC
- STROKE LENGTH:
- 54,50 MM
$154.95 -
WISECO Piston - Standard - Kawasaki KX 125 626M05400
WISECO
$154.95A worn or damaged piston directly compromises combustion efficiency, throttle response, and engine longevity—especially in high-RPM 2-stroke applications where precision tolerances are critical. The Wiseco 626M05400 restores your KX125 to factory...626M05400- SKU:
- 626M05400
- Availability:
- Ships Same Business Day
- Weight:
- 0.42 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
- BORE - OVERSIZE METRIC:
- STANDARD
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 54,50 MM
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 124 CC
- RIDING STYLE:
- OFF-ROAD
$154.95Qty in Cart: 0Quantity:Price:$154.95Subtotal: -
Wiseco Piston Kit 67.50 mm for Kawasaki KX 250 1996-2001 617M06750
WISECO
$221.95A worn or damaged piston directly kills your KX250's throttle response and compression, forcing you to either rebuild or replace the entire top-end. The Wiseco 617M06750 restores full power and reliability with a forged piston kit engineered specifically...617M06750- SKU:
- 617M06750
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- BORE - OVERSIZE:
- +1,10 MM
- STROKE LENGTH METRIC:
- 72.00 MM
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- +1.10 MM
- BORE SIZE METRIC:
- 67.50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
- DISPLACEMENT:
- 249 CC
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 72,00 MM
$221.95Qty in Cart: 0Quantity:Price:$221.95Subtotal: -
Wiseco Piston Kit Kawasaki KX 250 1992-2001 67.00 mm 617M06700
WISECO
$221.95A worn or damaged piston directly compromises engine compression, throttle response, and reliability—especially critical in 2-stroke racing engines where precision tolerances determine the difference between winning and mechanical failure. The Wiseco...617M06700- SKU:
- 617M06700
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 72,00 MM
- BORE - OVERSIZE METRIC:
- +0.60 MM
- BORE SIZE METRIC:
- 67.00 MM
- DISPLACEMENT:
- 249 CC
- UNITS:
- EACH
- BORE - OVERSIZE:
- +0,60 MM
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 72.00 MM
$221.95Qty in Cart: 0Quantity:Price:$221.95Subtotal: -
Wiseco Piston Kit 68.50mm for 1997-2001 Honda CR250R 702M06850
WISECO
$224.95If you're rebuilding a 1997-2001 Honda CR250R, piston quality directly impacts throttle response, combustion efficiency, and engine longevity. Wiseco's precision-forged construction delivers the reliability and performance demanded by serious 2-stroke...614M06850- SKU:
- 614M06850
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- BORE - OVERSIZE:
- +2,10 MM
- STROKE LENGTH METRIC:
- 72.00 MM
- BORE SIZE METRIC:
- 68.25 MM
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- DISPLACEMENT:
- 249 CC
- STROKE LENGTH:
- 72,00 MM
- BORE - OVERSIZE METRIC:
- +2.10 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
$224.95Qty in Cart: 0Quantity:Price:$224.95Subtotal: -
Wiseco Piston 1.00mm Oversize Honda CR250R 2001 614M06750
WISECO
$199.95When your CR250R's piston shows signs of wear or you're building up displacement with a 1.00mm oversize, a quality replacement is non-negotiable. Wiseco's aerospace-grade aluminum construction withstands the extreme combustion pressures of 2-stroke...614M06750- SKU:
- 614M06750
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 249 CC
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH METRIC:
- 72.00 MM
- STROKE LENGTH:
- 72,00 MM
- PISTON MATERIAL:
- ALUMINUM
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
- BORE SIZE METRIC:
- 67.50 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
$199.95Qty in Cart: 0Quantity:Price:$199.95Subtotal: -
Wiseco Piston Kit 0.50mm Oversize Honda CR250R 1986-1996 614M06700
WISECO
$199.95If you're running a 1986-1996 Honda CR250R, a worn or damaged piston directly kills power delivery and compression. The Wiseco 614M06700 restores—and exceeds—original performance with a high-silicon aluminum construction built to handle the extreme heat...614M06700- SKU:
- 614M06700
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- BORE SIZE METRIC:
- 67.00 MM
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH METRIC:
- 72.00 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- DISPLACEMENT:
- 249 CC
- STROKE LENGTH:
- 72,00 MM
- BORE - OVERSIZE:
- +0,50 MM
- PISTON MATERIAL:
- ALUMINUM
- PISTON MATERIAL:
- FORGED
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$199.95Qty in Cart: 0Quantity:Price:$199.95Subtotal: -
Wiseco Piston Kit Standard 66.40mm Honda CR250R 1986-1996 614M06640
WISECO
$221.95If you're running a CR250R from the golden era of 2-stroke racing, piston wear is inevitable—and a worn piston tanks power, efficiency, and reliability. The Wiseco 614M06640 is a direct replacement built to OEM specifications with high-silicon forged...614M06640- SKU:
- 614M06640
- Availability:
- Ships Same Business Day
- Weight:
- 0.68 LBS
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 66.40 MM
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
- DISPLACEMENT:
- 249 CC
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH:
- 72,00 MM
- STROKE LENGTH METRIC:
- 72.00 MM
$221.95 -
Wiseco Piston Kit +2.00 mm Yamaha YZ 250 1988-1991 605M07000
WISECO
$224.95If you're running a vintage Yamaha YZ250 or WR250 two-stroke, piston wear directly impacts power delivery, throttle response, and engine longevity. The Wiseco 605M07000 is a purpose-built replacement that restores lost compression and responsiveness...605M07000- SKU:
- 605M07000
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- DISPLACEMENT:
- 246,8 CC
- STROKE LENGTH METRIC:
- 68.00 MM
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE:
- +2,00 MM
- BORE - OVERSIZE METRIC:
- +2.00 MM
- BORE SIZE METRIC:
- 70.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 68,00 MM
- UNITS:
- EACH
$224.95Qty in Cart: 0Quantity:Price:$224.95Subtotal:
