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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Wiseco 66mm 10.25:1 Piston Kit for 1992-2002 Honda XR200R PK1125
WISECO
$204.95Whether you're rebuilding a worn XR200R or restoring a dormant XL185S to peak performance, a quality piston kit is essential for reliable power delivery and engine longevity. The Wiseco PK1125 delivers OEM-equivalent fitment with precision CNC-machined...09030270- SKU:
- 09030270
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- STROKE LENGTH METRIC:
- 57.80 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 66.00 MM
- MODEL:
- FORGED SERIES
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- DISPLACEMENT:
- 192 CC
- PISTON DIAMETER METRIC:
- 65.95 MM
- BORE - OVERSIZE:
- +0,50 MM
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- NON-COATED
- UNITS:
- KIT
$204.95Qty in Cart: 0Quantity:Price:$204.95Subtotal: -
Wiseco Yamaha YZ85 2002-2018 Piston Kit with Gaskets PK1343
WISECO
$214.95When your YZ85's top-end starts losing compression or showing signs of wear, a quality piston kit is essential to restore engine performance and reliability. The Wiseco PK1343 delivers OEM-spec fitment with precision CNC machining and aerospace-grade...09030271- SKU:
- 09030271
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 47.80 MM
- TYPE:
- TOP END
- BORE - OVERSIZE:
- STANDARD
- DISPLACEMENT:
- 103,5 CC
- MODEL:
- RACER'S CHOICE
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 52.50 MM
- COOLING SYSTEM:
- LIQUID COOLED
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- REBUILD KIT
- UNITS:
- EACH
$214.95Qty in Cart: 0Quantity:Price:$214.95Subtotal: -
Wiseco Piston Kit with Gaskets 40mm Bore for Yamaha PW50 1981-2025 PK1157
WISECO
$171.95A worn or damaged piston directly throttles your PW50's performance, causing compression loss, poor throttle response, and accelerated engine wear. The Wiseco PK1157 restores full compression integrity and thermal efficiency with precision-forged...09030275- SKU:
- 09030275
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- BORE SIZE METRIC:
- 40.00 MM
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- COOLING SYSTEM:
- AIR COOLED
- DISPLACEMENT:
- 49 CC
- PISTON MATERIAL:
- ALUMINUM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 39.20 MM
- UNITS:
- EACH
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- RACER'S CHOICE
$171.95 -
Wiseco Yamaha YZ125 2003-2004 Piston Kit with Gaskets PK1344
WISECO
$224.95Your YZ125's piston is the heart of engine performance—worn or undersized pistons rob you of power, throttle response, and reliability. The Wiseco PK1344 Pro-Lite Kit restores that performance with precision-engineered components built to survive the...09030283- SKU:
- 09030283
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- PISTON DIAMETER METRIC:
- 53.95 MM
- SKIRT COATING:
- NON-COATED
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE METRIC:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 125 CC
- MODEL:
- PRO-LITE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
$224.95Qty in Cart: 0Quantity:Price:$224.95Subtotal: -
Wiseco Piston Kit for Honda CR80R 1993-2002 PK1185
WISECO
$214.95The CR80R demands a piston kit that can handle high RPM abuse while maintaining bore integrity—the Wiseco PK1185 delivers exactly that. This CNC-machined, aerospace-grade aluminum piston assembly restores lost compression and sealing, bringing your...09030285- SKU:
- 09030285
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
- BORE - OVERSIZE METRIC:
- +5.00 MM
- COOLING SYSTEM:
- LIQUID COOLED
- UNITS:
- EACH
- BORE SIZE METRIC:
- 52.00 MM
- MODEL:
- RACER'S CHOICE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- BORE - OVERSIZE:
- +5,00 MM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 47.80 MM
- DISPLACEMENT:
- 101,5 CC
- PISTON MATERIAL:
- ALUMINUM
$214.95Qty in Cart: 0Quantity:Price:$214.95Subtotal: -
Wiseco 54mm Piston Kit with Gaskets for 2003 Honda CR125R PK1265
WISECO
$243.95A worn or damaged piston directly compromises your CR125R's compression, throttle response, and fuel efficiency. This complete Wiseco kit eliminates guesswork with OEM-spec fitment and quality gaskets, getting your bike back to peak performance without...09030286- SKU:
- 09030286
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 54.50 MM
- UNITS:
- KIT
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 125 CC
- MODEL:
- PRO-LITE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- PISTON DIAMETER METRIC:
- 53.95 MM
- SKIRT COATING:
- NON-COATED
$243.95 -
Wiseco Piston Kit with Gaskets for 1993-1998 Suzuki RMX250 PK1339
WISECO
$277.95A worn or damaged piston directly compromises combustion efficiency, throttle response, and overall engine reliability—especially critical on a 2-stroke like the RMX250 where every combustion cycle demands precision. The Wiseco PK1339 Pro-Lite kit...09030287- SKU:
- 09030287
- Availability:
- Ships Same Business Day
- Weight:
- 1.50 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON DIAMETER METRIC:
- 66.94 MM
- PRODUCT NAME:
- REBUILD KIT
- BORE - OVERSIZE:
- STANDARD
- DISPLACEMENT:
- 246 CC
- ENGINE TYPE:
- 2-STROKE
- SKIRT COATING:
- NON-COATED
- STROKE LENGTH METRIC:
- 70.80 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- BORE SIZE METRIC:
- 67.00 MM
- MODEL:
- PRO-LITE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
$277.95 -
Wiseco Yamaha YZ125 2001 54mm Piston Kit PK1348
WISECO
$225.95If you're running a 2001 YZ125 and want to maximize power output without sacrificing reliability, a quality piston kit is non-negotiable. The Wiseco PK1348 delivers the precision engineering and lightweight construction that separates competitive riders...09030288- SKU:
- 09030288
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- DISPLACEMENT:
- 124 CC
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 54.00 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- MODEL:
- PRO-LITE
- PISTON DIAMETER METRIC:
- 53.95 MM
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- NON-COATED
- UNITS:
- KIT
$225.95 -
Wiseco Piston Kit for Honda CR250R 1992-1996 PK1128
WISECO
$259.95If you're running a CR250R from the early '90s, piston wear directly impacts your engine's ability to hold compression and deliver peak power. The Wiseco PK1128 restores that lost performance through precision engineering and proven materials, giving you...09030292- SKU:
- 09030292
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- BORE SIZE METRIC:
- 66.40 MM
- PISTON DIAMETER METRIC:
- 66.36 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 249 CC
- MODEL:
- PRO-LITE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- SKIRT COATING:
- NON-COATED
- STROKE LENGTH METRIC:
- 72.00 MM
$259.95Qty in Cart: 0Quantity:Price:$259.95Subtotal: -
Wiseco Piston Honda CRF450R 2002 431M07000
WISECO
$199.95If you're rebuilding a Honda CRF450R engine or refreshing a high-mileage top end, a quality OEM-equivalent piston is non-negotiable—it's the foundation of reliable horsepower and longevity. The Wiseco Piston (431M07000) delivers the precision fit and...431M07000- SKU:
- 431M07000
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- PISTON DIAMETER METRIC:
- 69.95 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- DISPLACEMENT:
- 248 CC
- ENGINE TYPE:
- 2-STROKE
- SKIRT COATING:
- NON-COATED
- STROKE LENGTH METRIC:
- 64.40 MM
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 70.00 MM
- MODEL:
- FORGED SERIES
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
$199.95Qty in Cart: 0Quantity:Price:$199.95Subtotal: -
Wiseco Piston Honda CRF450R 2002-2008 431M07050
WISECO
$221.95If you're running a Honda CRF450R from the 2002-2008 generation, a worn or damaged piston directly impacts combustion efficiency, throttle response, and overall engine reliability. The Wiseco 431M07050 piston kit restores lost performance while...431M07050- SKU:
- 431M07050
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- BORE - OVERSIZE METRIC:
- +0.50 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH METRIC:
- 64.40 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- BORE - OVERSIZE:
- +0,50 MM
- DISPLACEMENT:
- 248 CC
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- NON-COATED
- BORE SIZE METRIC:
- 70.50 MM
- MODEL:
- FORGED SERIES
- PISTON DIAMETER METRIC:
- 70.45 MM
- UNITS:
- KIT
$221.95Qty in Cart: 0Quantity:Price:$221.95Subtotal: -
Wiseco Piston Kit 71mm Oversize for Honda CR250R 1978-1980 431M07100
WISECO
$221.95If you're running a Honda CR250R with high mileage or planning a performance build, a quality piston kit is essential to restore compression and unlock the engine's full potential. Wiseco's forged construction and CNC precision ensure reliable power...431M07100- SKU:
- 431M07100
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- MODEL:
- FORGED SERIES
- SKIRT COATING:
- NON-COATED
- DISPLACEMENT:
- 248 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 70.95 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 64.40 MM
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- BORE SIZE METRIC:
- 71.00 MM
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
$221.95 -
Wiseco Piston Kit 72mm Oversize for Honda CR250R 1978-1980 431M07200
WISECO
$232.95If you're rebuilding a CR250R or ATC250R engine, piston quality directly impacts reliability and power delivery. Wiseco's high-silicon aluminum construction handles the extreme combustion pressures of 2-stroke performance while maintaining the tight...431M07200- SKU:
- 431M07200
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- DISPLACEMENT:
- 248 CC
- PISTON DIAMETER METRIC:
- 71.95 MM
- SKIRT COATING:
- NON-COATED
- MODEL:
- FORGED SERIES
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +2.00 MM
- BORE SIZE METRIC:
- 72.00 MM
- STROKE LENGTH METRIC:
- 64.40 MM
- BORE - OVERSIZE:
- +2,00 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
$232.95Qty in Cart: 0Quantity:Price:$232.95Subtotal: -
Wiseco 85mm Piston Kit for 1983-1984 Honda XR350R 4286M08500
WISECO
$184.95If you're running a 1983-1984 Honda XR350R, piston wear directly impacts power delivery, fuel efficiency, and engine reliability. The Wiseco 85mm Piston Kit restores lost performance and allows you to safely push higher compression ratios without...4286M08500- SKU:
- 4286M08500
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- DISPLACEMENT:
- 339 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH METRIC:
- 61.30 MM
- BORE SIZE METRIC:
- 85.00 MM
- ENGINE TYPE:
- 4-STROKE
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- PISTON DIAMETER METRIC:
- 84.95 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MODEL:
- FORGED SERIES
- SKIRT COATING:
- NON-COATED
$184.95 -
Wiseco Piston Kit Standard 86mm Kawasaki KX 500 1988-2004 575M08600
WISECO
$243.95The Wiseco 86mm piston kit is engineered for the KX500 to deliver measurable gains in throttle response and combustion efficiency. If you're running stock pistons, you're leaving horsepower on the table—this upgrade is essential for both competitive...575M08600- SKU:
- 575M08600
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 86.00 MM
- UNITS:
- EACH
- BORE SIZE METRIC:
- 86.00 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 86,00 MM
- DISPLACEMENT:
- 499 CC
$243.95Qty in Cart: 0Quantity:Price:$243.95Subtotal: -
Wiseco Piston Kit 1988-2004 Kawasaki KX 500 575M08650
WISECO
$234.95If you're running a KX500 at the limit—whether on the track or the trail—piston wear and loss of compression will eventually compromise your power. The Wiseco Piston Kit restores full performance potential and adds measurable horsepower through advanced...575M08650- SKU:
- 575M08650
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- BORE SIZE METRIC:
- 86.50 MM
- DISPLACEMENT:
- 499 CC
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 86,00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH METRIC:
- 86.00 MM
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- +0,50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
$234.95Qty in Cart: 0Quantity:Price:$234.95Subtotal: -
Wiseco Piston Kit 1988-2004 Kawasaki KX 500 575M08700
WISECO
$234.95If you're rebuilding a KX500 or pushing your machine harder on the track, piston quality directly impacts power delivery, reliability, and how long your engine lasts between rebuilds. The Wiseco 575M08700 kit delivers the precision engineering and...575M08700- SKU:
- 575M08700
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- BORE - OVERSIZE:
- +1,00 MM
- DISPLACEMENT:
- 499 CC
- PRODUCT NAME:
- PISTON
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 86.00 MM
- UNITS:
- EACH
- STROKE LENGTH:
- 86,00 MM
- BORE SIZE METRIC:
- 87.00 MM
- RIDING STYLE:
- OFF-ROAD
$234.95Qty in Cart: 0Quantity:Price:$234.95Subtotal: -
Wiseco Piston Standard Yamaha YTZ250 Tri-Z 1985 515M06800
WISECO
$204.95A worn or damaged piston compromises engine efficiency, throttle response, and overall reliability—especially critical for serious riders pushing their YTZ 250 Tri-Z to its limits. The Wiseco piston restores lost performance through precision engineering...515M06800- SKU:
- 515M06800
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- DISPLACEMENT:
- 246,8 CC
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 68.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 68,00 MM
- UNITS:
- EACH
- STROKE LENGTH METRIC:
- 68.00 MM
- PISTON MATERIAL:
- FORGED
$204.95Qty in Cart: 0Quantity:Price:$204.95Subtotal: -
Wiseco Piston Kit Yamaha IT 250 1983 515M06900
WISECO
$223.95A worn or damaged piston directly compromises engine compression, throttle response, and overall reliability—especially critical in a two-stroke where the piston cycles thousands of times per minute. The Wiseco 515M06900 restores your IT 250 to factory...515M06900- SKU:
- 515M06900
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- BORE - OVERSIZE:
- +1,00 MM
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 68.00 MM
- DISPLACEMENT:
- 246,8 CC
- BORE - OVERSIZE METRIC:
- +1.00 MM
- BORE SIZE METRIC:
- 69.00 MM
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH:
- 68,00 MM
- UNITS:
- EACH
$223.95Qty in Cart: 0Quantity:Price:$223.95Subtotal: -
Wiseco Piston Standard Kawasaki KX 80 1984-1985 514M04800
WISECO
$141.95A piston is the engine's hardest-working component—when it fails, your bike is done. The Wiseco Piston for Kawasaki KX80 (1984-1985) delivers the durability and power output you need to push your bike hard without gambling on reliability. Built with...514M04800- SKU:
- 514M04800
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- BORE SIZE METRIC:
- 48.00 MM
- DISPLACEMENT:
- 82 CC
- STROKE LENGTH:
- 45,80 MM
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- BORE - OVERSIZE:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- STROKE LENGTH METRIC:
- 45.80 MM
$141.95Qty in Cart: 0Quantity:Price:$141.95Subtotal:
