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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Hinson Racing Clutch Cover for Honda CRF450R 2002-2008 C224
HINSON RACING
$159.99Stock clutch covers overheat under sustained throttle, robbing you of reliable engagement when it matters most. The Hinson Racing Clutch Cover solves this with optimized cooling geometry and reinforced construction that handles the demands of competitive...C154- SKU:
- C154
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- COLOR/FINISH:
- BLACK
- MATERIAL:
- T-6 ALUMINUM
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
- MODEL:
- BILLETPROOF
$159.99 -
Wiseco Piston Kit 48mm Bore 2002-2023 Suzuki RM85 806M04800
WISECO
$132.95The Wiseco 806M04800 piston kit delivers the durability and power output you need to stay competitive in the RM85 class, whether you're chasing podiums or pushing limits on the trail. Built from forged high-silicon aluminum, this piston withstands the...806M04800- SKU:
- 806M04800
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- STROKE LENGTH:
- 46,80 MM
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 46.80 MM
- UNITS:
- EACH
- DISPLACEMENT:
- 84.7 CC
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 48.00 MM
- PISTON MATERIAL:
- FORGED
$132.95 -
Wiseco Piston Standard Yamaha YZ 85 2002-2021 805M04750
WISECO
$132.95The stock piston in your YZ 85 can't keep up with the demands of competitive racing or aggressive trail riding. Wiseco's forged piston delivers the compression consistency, durability, and power output you need to stay competitive across multiple seasons...805M04750- SKU:
- 805M04750
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH:
- 47,80 MM
- STROKE LENGTH METRIC:
- 47.80 MM
- UNITS:
- EACH
- DISPLACEMENT:
- 85 CC
- BORE SIZE METRIC:
- 47.50 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
$132.95 -
Wiseco Piston Kit for Yamaha YZ 250 2002-2025 804M06640
WISECO
$171.95If you're running a Yamaha YZ 250 in competitive racing or high-performance trail riding, stock pistons won't cut it. The Wiseco 804M06640 kit delivers the strength and precision needed to handle aggressive tuning, boost horsepower, and maintain...804M06640- SKU:
- 804M06640
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- STROKE LENGTH METRIC:
- 72.00 MM
- BORE SIZE METRIC:
- 66.40 MM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 249 CC
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 72,00 MM
$171.95 -
Wiseco Piston Kit 41.50mm KTM 50SX LC 2001-2008 803M04150
WISECO
$109.95The Wiseco Piston Kit delivers the durability and performance gains your KTM 50SX LC demands during high-RPM racing and aggressive trail riding. High-silicon aluminum construction and E-coat protection resist thermal stress and wear, while the optimized...803M04150- SKU:
- 803M04150
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- BORE - OVERSIZE METRIC:
- +2.00 MM
- ENGINE TYPE:
- 2-STROKE
- DISPLACEMENT:
- 49 CC
- STROKE LENGTH:
- 40,00 MM
- BORE SIZE METRIC:
- 41.50 MM
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- +2,00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 40.00 MM
- UNITS:
- EACH
$109.95 -
Wiseco 39.50mm Piston Kit for KTM 50 SX 2001-2008 803M03950
WISECO
$116.95The Wiseco 39.50mm piston kit delivers the compression ratio stability and durability your KTM 50 SX demands during sustained racing or aggressive trail riding. Built from high-silicon aluminum alloy and featuring E-coated critical surfaces, this forged...803M03950- SKU:
- 803M03950
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH:
- 40,00 MM
- UNITS:
- EACH
- BORE SIZE METRIC:
- 39.50 MM
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 40.00 MM
- DISPLACEMENT:
- 49 CC
$116.95 -
Wiseco 125cc 54mm Piston Kit for KTM 125 SX 2001-2024 786M05400
WISECO
$160.95The Wiseco 786M05400 piston kit delivers the durability and precision you need to extract maximum performance from your KTM 125 SX. Built from high-silicon aluminum and E-coated for wear resistance, this complete kit keeps your engine reliable through...786M05400- SKU:
- 786M05400
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- STREET
- UNITS:
- EACH
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 54.50 MM
- STROKE LENGTH:
- 54,50 MM
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 124 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
$160.95 -
Wiseco Piston Kit Kawasaki KX 85 2001-2013 782M04850
WISECO
$132.95If you're running a KX 85 in competitive or trail racing, piston durability and horsepower output directly impact your results. Wiseco's forged high-silicon aluminum construction withstands the extreme pressures of two-stroke racing while the optimized...782M04850- SKU:
- 782M04850
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- BORE - OVERSIZE:
- STANDARD
- DISPLACEMENT:
- 84,9 CC
- ENGINE TYPE:
- 2-STROKE
- BORE SIZE METRIC:
- 48.50 MM
- STROKE LENGTH:
- 45,80 MM
- STROKE LENGTH METRIC:
- 45.80 MM
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
$132.95 -
Wiseco Piston Kit Yamaha WaveRunner GP1200 1997-1999 757M08500
WISECO
$159.95When your WaveRunner GP1200 demands peak performance, a compromised piston setup costs you power, reliability, and race-day confidence. The Wiseco 757M08500 piston kit delivers the durability and precision fit your 2-cycle engine needs to perform...757M08500- SKU:
- 757M08500
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- BORE SIZE METRIC:
- 85.00 MM
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- DISPLACEMENT:
- 1156 CC
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 771 CC
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
$159.95 -
Wiseco Piston 54.50 mm Oversize for Suzuki RM 125 2000-2003 754M05450
WISECO
$160.95When you're pushing your RM 125 to the limit, your piston needs to match your ambition. The Wiseco 54.50 mm oversize piston delivers the strength and precision required to handle high-RPM racing demands while improving power output and engine reliability...754M05450- SKU:
- 754M05450
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 54.50 MM
- UNITS:
- EACH
- STROKE LENGTH:
- 54,50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 54.50 MM
- DISPLACEMENT:
- 124,8 CC
- BORE - OVERSIZE:
- +0,50 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
$160.95 -
Wiseco Piston Kit Standard 44.5mm Bore 2000-2025 Kawasaki KX65 Suzuki RM65 752M04450
WISECO
$128.95When you're pushing your KX65 or RM65 to the limit on the track, your piston needs to handle extreme combustion pressures and sustained RPMs without compromise. The Wiseco Piston Kit delivers the durability and power output you need to stay competitive,...752M04450- SKU:
- 752M04450
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- STROKE LENGTH:
- 41,60 MM
- BORE - OVERSIZE:
- STANDARD
- DISPLACEMENT:
- 64 CC
- ENGINE TYPE:
- 2-STROKE
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 44.50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 41.60 MM
- UNITS:
- EACH
$128.95 -
Wiseco Piston Kit 1.00 mm Oversize for Yamaha YZ 250 1999-2022 677M06900
WISECO
$210.95If you're running a YZ 250 in competitive trail or race conditions, a worn or stock piston limits your engine's potential for power and reliability. The Wiseco +1.00 mm piston kit delivers the compression increase and durability you need to extract...677M06900- SKU:
- 677M06900
- Availability:
- Ships Same Business Day
- Weight:
- 0.72 LBS
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- BORE SIZE METRIC:
- 69.00 MM
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 68.00 MM
- DISPLACEMENT:
- 246,8 CC
- ENGINE TYPE:
- 2-STROKE
- STROKE LENGTH:
- 68,00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
$210.95 -
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 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 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 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 Yamaha YZ250 1999-2024 66.40mm 804M06640
WISECO
$219.95A worn or damaged piston directly compromises combustion efficiency, throttle response, and engine reliability—especially in high-demand 2-stroke applications. The Wiseco Piston Kit 605M06900 restores your YZ250's performance with forged aluminum...605M06900- SKU:
- 605M06900
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- DISPLACEMENT:
- 246,8 CC
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE SIZE METRIC:
- 69.00 MM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH:
- 68,00 MM
- STROKE LENGTH METRIC:
- 68.00 MM
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
$219.95 -
Wiseco Piston 68.50mm Yamaha YZ250 1988-1998 605M06850
WISECO
$219.95If you're running a Yamaha YZ250 two-stroke, piston wear directly impacts throttle response, compression, and reliability. The Wiseco 605M06850 is a forged-aluminum piston kit engineered to restore—or exceed—OEM performance with the supporting components...605M06850- SKU:
- 605M06850
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- STROKE LENGTH METRIC:
- 68.00 MM
- BORE - OVERSIZE:
- +0,50 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 68.50 MM
- STROKE LENGTH:
- 68,00 MM
- DISPLACEMENT:
- 246,8 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
$219.95 -
Wiseco Piston Kit 57.00 mm for Yamaha YZ 125 1986-1988 559M05700
WISECO
$154.95If you're running a Yamaha YZ125 two-stroke, piston wear is inevitable—and it directly impacts throttle response, compression, and overall power delivery. The Wiseco 559M05700 restores your engine to peak performance with precision-forged construction...559M05700- SKU:
- 559M05700
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 50,00 MM
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 57.00 MM
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 50.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 123 CC
$154.95
