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 Kit with Gaskets for Kawasaki KX250 2007-2008 PK1598
WISECO
$307.95If you're rebuilding a KX250F or pushing your engine to its limits, piston quality directly impacts reliability and power output. The Wiseco PK1598 delivers forged aluminum construction that handles the demands of competitive riding while maintaining the...09030932- SKU:
- 09030932
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- PRODUCT NAME:
- REBUILD KIT
- ENGINE TYPE:
- 4-STROKE
- PISTON DIAMETER METRIC:
- 76.96 MM
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- TYPE:
- TOP END
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- ARMORGLIDE®
- UNITS:
- KIT
- BORE SIZE METRIC:
- 77.00 MM
- DISPLACEMENT:
- 250 CC
- MODEL:
- FORGED SERIES
- STROKE LENGTH METRIC:
- 53.60 MM
$307.95 -
Wiseco Piston Kit 47mm 10.5:1 Compression for Honda CRF70F 2004-2012 PK1729
WISECO
$182.95If you're running a CRF70F and want measurable gains in power and throttle response, the Wiseco PK1729 piston kit delivers the compression ratio and engineering precision needed to unlock your bike's potential. This is a direct bolt-in upgrade that...09030933- SKU:
- 09030933
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- SKIRT COATING:
- NON-COATED
- UNITS:
- KIT
- DISPLACEMENT:
- 72 CC
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- COMPRESSION RATIO IMPERIAL:
- 10.5:1
- PISTON DIAMETER METRIC:
- 46.97 MM
- PRODUCT NAME:
- REBUILD KIT
- STROKE LENGTH METRIC:
- 41.40 MM
- BORE SIZE METRIC:
- 47.00 MM
- MODEL:
- FORGED SERIES
$182.95 -
Wiseco Piston Kit for Kawasaki KX450F 2009-2012 13.5:1 Compression PK1840
WISECO
$339.95If you're running a 2009-2012 Kawasaki KX450F at the edge of its limits, piston failure isn't a question of if—it's when. The Wiseco PK1840 raises your compression ratio to 13.5:1, unlocking measurable gains in power and throttle response while...09030935- SKU:
- 09030935
- Availability:
- Ships Same Business Day
- Weight:
- 1.85 LBS
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- FORGED SERIES
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 62.10 MM
- TYPE:
- TOP END
- UNITS:
- KIT
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- PRODUCT NAME:
- REBUILD KIT
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 96.00 MM
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- DISPLACEMENT:
- 449 CC
- PISTON DIAMETER METRIC:
- 95.95 MM
- SKIRT COATING:
- ARMORGLIDE®
$339.95Qty in Cart: 0Quantity:Price:$339.95Subtotal: -
Wiseco Piston Kit Yamaha YZ250F 2008-2011 PK1844
WISECO
$309.95A worn or failing piston directly compromises engine performance, reliability, and your race results. The Wiseco PK1844 restores—and exceeds—OEM specifications with aerospace-grade forged aluminum and precision CNC machining, delivering the durability...09030937- SKU:
- 09030937
- Availability:
- Ships Same Business Day
- Weight:
- 1.20 LBS
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- PISTON DIAMETER METRIC:
- 76.95 MM
- PRODUCT NAME:
- REBUILD KIT
- SKIRT COATING:
- ARMORGLIDE®
- BORE SIZE METRIC:
- 77.00 MM
- ENGINE TYPE:
- 4-STROKE
- TYPE:
- TOP END
- DISPLACEMENT:
- 250 CC
- MODEL:
- FORGED SERIES
- STROKE LENGTH METRIC:
- 53.60 MM
- UNITS:
- KIT
$309.95Qty in Cart: 0Quantity:Price:$309.95Subtotal: -
Wiseco Piston Kit with Gaskets for Yamaha YZ250F 2008-2011 PK1845
WISECO
$344.95A top-end rebuild is essential for maintaining peak performance in your YZ250F, and the Wiseco PK1845 kit delivers everything needed in one complete package. This precision-forged piston and gasket set restores compression efficiency and throttle...09030938- SKU:
- 09030938
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- PISTON DIAMETER METRIC:
- 76.95 MM
- TYPE:
- TOP END
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- PRODUCT NAME:
- REBUILD KIT
- COMPRESSION RATIO IMPERIAL:
- 14.0:1
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- ARMORGLIDE®
- UNITS:
- KIT
- BORE SIZE METRIC:
- 77.00 MM
- DISPLACEMENT:
- 250 CC
- MODEL:
- FORGED SERIES
- STROKE LENGTH METRIC:
- 53.60 MM
$344.95Qty in Cart: 0Quantity:Price:$344.95Subtotal: -
Wiseco Piston Kit for Kawasaki KX250F 2011-2014 77mm 13.5:1 Compression PK1879
WISECO
$299.95A top-end rebuild is critical for maintaining peak performance in your KX250F, and Wiseco's precision-forged pistons deliver the durability and power consistency you need for consistent lap times. This complete kit includes everything required for a...09030941- SKU:
- 09030941
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- ARMORGLIDE®
- UNITS:
- KIT
- BORE SIZE METRIC:
- 77.00 MM
- DISPLACEMENT:
- 250 CC
- MODEL:
- FORGED SERIES
- STROKE LENGTH METRIC:
- 53.60 MM
- PISTON DIAMETER METRIC:
- 76.96 MM
- TYPE:
- TOP END
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- PRODUCT NAME:
- REBUILD KIT
$299.95Qty in Cart: 0Quantity:Price:$299.95Subtotal: -
Wiseco KX250F 2011-2014 Piston Kit with Gaskets PK1880
WISECO
$339.95The stock piston in your KX250F limits your engine's potential. Wiseco's PK1880 kit delivers measurable gains in compression ratio and throttle response while the ArmorGlide skirt coating extends engine life under high-RPM load. If you're chasing lap...09030942- SKU:
- 09030942
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- SKIRT COATING:
- ARMORGLIDE®
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- PISTON DIAMETER METRIC:
- 76.96 MM
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- PRODUCT NAME:
- REBUILD KIT
- BORE SIZE METRIC:
- 77.00 MM
- COMPRESSION RATIO IMPERIAL:
- 14.5:1
- DISPLACEMENT:
- 250 CC
- MODEL:
- FORGED SERIES
- STROKE LENGTH METRIC:
- 53.60 MM
$339.95Qty in Cart: 0Quantity:Price:$339.95Subtotal: -
Wiseco Piston Kit 56mm 2mm Oversize Kawasaki KX125 1998 719M05600
WISECO
$179.95If you're running a 1998 Kawasaki KX125 and want measurable gains in throttle response and engine durability, a quality piston kit is non-negotiable. The Wiseco 719M05600 delivers the precision engineering and material science required to safely push...719M05600- SKU:
- 719M05600
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- DISPLACEMENT:
- 124 CC
- STROKE LENGTH:
- 54,50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 54.50 MM
- UNITS:
- EACH
- BORE - OVERSIZE:
- +2,00 MM
- BORE - OVERSIZE METRIC:
- +2.00 MM
- BORE SIZE METRIC:
- 56.00 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
$179.95Qty in Cart: 0Quantity:Price:$179.95Subtotal: -
Wiseco Piston Kit Sea-Doo 3D 947 DI 2006-2007 716M08850
WISECO
$166.10If you're running a Sea-Doo 3D 947 DI, piston wear directly impacts power delivery, fuel efficiency, and engine longevity. The Wiseco 716M08850 piston kit restores lost compression and responsiveness while providing the durability needed for sustained...716M08850- SKU:
- 716M08850
- Availability:
- Ships Same Business Day
- Weight:
- 1.25 LBS
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 88.50 MM
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- DISPLACEMENT:
- 960 CC
- PISTON MATERIAL:
- ALUMINUM
- BORE - OVERSIZE:
- +0,50 MM
- RIDING STYLE:
- WATERCRAFT
$166.10 -
Wiseco Piston Kit 89mm for Sea-Doo GSX Limited 1998-1999 716M08900
WISECO
$174.95Worn or damaged pistons compromise combustion efficiency, throttle response, and engine longevity—especially in high-performance applications. The Wiseco 89mm Piston Kit is engineered to restore and exceed OEM specifications, delivering precise fitment...716M08900- SKU:
- 716M08900
- Availability:
- Ships Same Business Day
- Weight:
- 1.20 LBS
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 89.00 MM
- RIDING STYLE:
- WATERCRAFT
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 971 CC
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- PISTON MATERIAL:
- ALUMINUM
$174.95 -
Wiseco Piston Kit 56mm Bore Kawasaki KX125 1986 741M05600
WISECO
$179.95OEM pistons wear down with regular use, losing compression and throttle response over time. The Wiseco 56mm Piston Kit restores your KX125 to peak performance with precision engineering and high-silicon aluminum construction that handles aggressive...741M05600- SKU:
- 741M05600
- Availability:
- Ships Same Business Day
- Weight:
- 0.44 LBS
- DISPLACEMENT:
- 124 CC
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 54,50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE:
- +2,00 MM
- BORE - OVERSIZE METRIC:
- +2.00 MM
- BORE SIZE METRIC:
- 56.00 MM
- ENGINE TYPE:
- 2-STROKE
- UNITS:
- EACH
$179.95Qty in Cart: 0Quantity:Price:$179.95Subtotal: -
Wiseco Piston Kit 66.40mm Standard Bore Suzuki RM250 1999 743M06640
WISECO
$199.95Worn or stock pistons limit your RM250's potential, sacrificing throttle response and peak power when you need it most. The Wiseco 66.40mm piston kit restores combustion efficiency with precision engineering and premium materials, giving you the...743M06640- SKU:
- 743M06640
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- STROKE LENGTH METRIC:
- 72.00 MM
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 72,00 MM
- UNITS:
- EACH
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- BORE SIZE METRIC:
- 66.40 MM
- RIDING STYLE:
- OFF-ROAD
$199.95Qty in Cart: 0Quantity:Price:$199.95Subtotal: -
Wiseco Piston Kit 2025 KTM 65 SX 2.00mm Oversize 746M04700
WISECO
$134.95The Wiseco Piston Kit delivers the reliability and precision your KTM 65 SX demands, whether you're chasing podium finishes or pushing limits on the trail. A 2.00mm oversize bore maximizes displacement for measurable gains in throttle response and...746M04700- SKU:
- 746M04700
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- DISPLACEMENT:
- 63,58 CC
- STROKE LENGTH:
- 40,00 MM
- STROKE LENGTH METRIC:
- 40.00 MM
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- +2.00 MM
- ENGINE TYPE:
- 2-STROKE
- BORE - OVERSIZE:
- +2,00 MM
- BORE SIZE METRIC:
- 47.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
$134.95Qty in Cart: 0Quantity:Price:$134.95Subtotal: -
Wiseco Piston Kit 78mm Bore KTM 380 SX 1998-2002 748M07800
WISECO
$243.95If you're running a KTM 380 SX or EXC, the factory piston won't cut it if you're serious about trail performance or track reliability. A quality piston kit like this Wiseco directly impacts throttle response, combustion efficiency, and engine...748M07800- SKU:
- 748M07800
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 77,00 MM
- BORE SIZE METRIC:
- 78.00 MM
- DISPLACEMENT:
- 368 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 77.00 MM
- UNITS:
- EACH
$243.95 -
Wiseco Piston Kit 79mm Bore 1998-2002 KTM 380 SX 748M07900
WISECO
$243.95Stock pistons in your KTM 380 SX reach their limits under aggressive riding and high-RPM demands. The Wiseco 79mm piston kit delivers the strength and precision your engine needs to maintain reliability while unlocking additional power—critical for...748M07900- SKU:
- 748M07900
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- BORE - OVERSIZE:
- +1,00 MM
- DISPLACEMENT:
- 368 CC
- STROKE LENGTH METRIC:
- 77.00 MM
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH:
- 77,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE SIZE METRIC:
- 79.00 MM
- PISTON MATERIAL:
- FORGED
$243.95 -
Wiseco Piston Standard Yamaha YZ 125 1998-2001 726M05400
WISECO
$154.95When you're pushing your YZ 125 to the limit, your piston is doing the hardest work in the engine—and a worn or damaged one will cost you power, reliability, and race results. The Wiseco 726M05400 is engineered to restore peak combustion efficiency while...726M05400- SKU:
- 726M05400
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- BORE SIZE METRIC:
- 54.00 MM
- STROKE LENGTH:
- 54,50 MM
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- UNITS:
- EACH
- DISPLACEMENT:
- 124 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
$154.95Qty in Cart: 0Quantity:Price:$154.95Subtotal: -
Wiseco Piston +0.50 mm Yamaha YZ 125 2000-2025 726M05450
WISECO
$154.95If you're running a YZ125 at the limit, piston wear and clearance issues will kill your power delivery and throttle response. The Wiseco +0.50mm piston restores compression and combustion efficiency to factory specifications—or better—with precision CNC...726M05450- SKU:
- 726M05450
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE - OVERSIZE:
- +0,50 MM
- DISPLACEMENT:
- 124 CC
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 54.50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 54.50 MM
- STROKE LENGTH:
- 54,50 MM
- ENGINE TYPE:
- 2-STROKE
- UNITS:
- EACH
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
$154.95Qty in Cart: 0Quantity:Price:$154.95Subtotal: -
Wiseco Piston Kit 54mm for Suzuki RM125 1989-1999 641M05400
WISECO
$162.95If you're rebuilding a RM125 or chasing more responsive power delivery, a quality piston kit is non-negotiable. Wiseco's 54mm design delivers the precision fit and lightweight construction that separates a stock rebuild from a genuinely competitive...641M05400- SKU:
- 641M05400
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- DISPLACEMENT:
- 123 CC
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 54.00 MM
- BORE SIZE METRIC:
- 54.00 MM
- STROKE LENGTH:
- 54,00 MM
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
$162.95 -
Wiseco Piston Kit 54.50 mm Suzuki RM125 1989-1999 641M05450
WISECO
$162.95If you're running a Suzuki RM125 from the '89–'99 generation, a worn or stock piston is costing you power and throttle response. The Wiseco Piston Kit delivers the precision engineering and material science needed to unlock real horsepower gains while...641M05450- SKU:
- 641M05450
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- BORE SIZE METRIC:
- 54.50 MM
- STROKE LENGTH METRIC:
- 54.00 MM
- BORE - OVERSIZE:
- +0,50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- DISPLACEMENT:
- 125 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH:
- 54,00 MM
$162.95Qty in Cart: 0Quantity:Price:$162.95Subtotal: -
Wiseco Piston +1.00 mm Suzuki RM 125 1989-1999 641M05500
WISECO
$154.95If you're running a Suzuki RM125 and want to unlock real gains in power and throttle response, a properly sized piston is where it starts. Wiseco's +1.00mm oversized piston delivers the durability and precision you need to push your engine hard without...641M05500- SKU:
- 641M05500
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- STROKE LENGTH METRIC:
- 54.00 MM
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 55.00 MM
- STROKE LENGTH:
- 54,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- DISPLACEMENT:
- 123 CC
- ENGINE TYPE:
- 2-STROKE
$154.95
