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 Piston Kit for Yamaha YZ250 1999-2001 +1.50 mm 605M06950
WISECO
$224.95If you're running a YZ250 and want to unlock measurable gains in power delivery and engine longevity, a quality piston kit is essential. Wiseco's forged-aluminum construction delivers the precision and durability demanded by serious 2-stroke riders. This...605M06950- SKU:
- 605M06950
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- BORE - OVERSIZE:
- +1,50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH:
- 68,00 MM
- BORE - OVERSIZE METRIC:
- +1.50 MM
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- BORE SIZE METRIC:
- 69.50 MM
- DISPLACEMENT:
- 246,8 CC
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 68.00 MM
$224.95Qty in Cart: 0Quantity:Price:$224.95Subtotal: -
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 54.00 mm Honda CR125R 2004 564M05400
WISECO
$154.95When a 2-stroke piston fails or shows signs of wear, your bike's performance and reliability suffer immediately. The Wiseco Piston Kit 595M05500 replaces worn components with forged aluminum construction and precision engineering, restoring combustion...595M05500- SKU:
- 595M05500
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- DISPLACEMENT:
- 125 CC
- UNITS:
- EACH
- BORE SIZE METRIC:
- 55.00 MM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 54.50 MM
- ENGINE TYPE:
- 2-STROKE
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH:
- 54,50 MM
$154.95 -
Wiseco Piston Kit 51.00mm Yamaha YZ80 1976-1980 457M05100
WISECO
$144.95If you're rebuilding a YZ80 or pushing your 2-stroke to the limit, a worn piston directly kills your power and efficiency. The Wiseco Piston Kit 569M05000 restores—or exceeds—OEM performance with precision-engineered components that handle high RPMs and...569M05000- SKU:
- 569M05000
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- BORE SIZE METRIC:
- 50.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- BORE - OVERSIZE:
- +2,00 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- BORE - OVERSIZE METRIC:
- +2.00 MM
- DISPLACEMENT:
- 82 CC
- STROKE LENGTH:
- 45,60 MM
- STROKE LENGTH METRIC:
- 45.60 MM
$144.95Qty in Cart: 0Quantity:Price:$144.95Subtotal: -
WISECO Piston - +1.00 mm - Yamaha YZ 80 569M04900
WISECO
$134.95A worn or damaged piston directly compromises your YZ80's compression, throttle response, and overall engine reliability. The Wiseco 569M04900 restores lost performance and durability with forged high-silicon aluminum engineered to handle the demands of...569M04900- SKU:
- 569M04900
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- BORE SIZE METRIC:
- 49.00 MM
- STROKE LENGTH:
- 45,60 MM
- UNITS:
- EACH
- BORE - OVERSIZE:
- +1,00 MM
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 82 CC
- STROKE LENGTH METRIC:
- 45.60 MM
$134.95Qty in Cart: 0Quantity:Price:$134.95Subtotal: -
Wiseco Piston Standard Yamaha YZ 250 1999-2022 560M06800
WISECO
$199.95A worn or damaged piston directly compromises combustion efficiency, throttle response, and engine longevity—especially in a high-revving 2-stroke like the YZ250. The Wiseco 560M06800 restores lost performance with precision-engineered geometry and...560M06800- SKU:
- 560M06800
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 246,8 CC
- PRODUCT NAME:
- PISTON
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH:
- 68,00 MM
- STROKE LENGTH METRIC:
- 68.00 MM
- UNITS:
- EACH
- BORE SIZE METRIC:
- 68.00 MM
- RIDING STYLE:
- OFF-ROAD
$199.95Qty in Cart: 0Quantity:Price:$199.95Subtotal: -
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 -
Wiseco Piston Kit Kawasaki KX 250 1990 1991 68.50 mm 556M06850
WISECO
$199.95If you're running a KX 250 two-stroke, piston wear directly impacts combustion efficiency, throttle response, and overall engine reliability. The Wiseco 556M06850 piston kit restores lost performance through precision engineering and premium materials,...556M06850- SKU:
- 556M06850
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- BORE - OVERSIZE:
- +1,10 MM
- BORE SIZE METRIC:
- 68.50 MM
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- +1.10 MM
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH:
- 70,00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- STROKE LENGTH METRIC:
- 70.00 MM
$199.95Qty in Cart: 0Quantity:Price:$199.95Subtotal: -
Wiseco Piston Standard Kawasaki KX 125 1995-1997 555M05600
WISECO
$154.95If you're running a KX 125 2-stroke, piston wear is inevitable—and when it happens, performance tanks fast. The Wiseco 555M05600 delivers OEM-equivalent fitment with proven durability, so you can trust it to handle aggressive riding without compromising...555M05600- SKU:
- 555M05600
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 56.00 MM
- DISPLACEMENT:
- 124 CC
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH:
- 50,6 MM
- STROKE LENGTH METRIC:
- 50.60 MM
- UNITS:
- EACH
$154.95 -
Wiseco Piston Kit for Honda TRX400EX 1999-2008 86mm Bore 10:1 Compression 4606M08600
WISECO
$210.95When you're pushing a Honda TRX400EX to its limits, your factory piston won't cut it. This Wiseco forged piston kit delivers the strength and precision needed to handle aggressive riding while unlocking real performance gains. Backed by Wiseco's proven...4606M08600- SKU:
- 4606M08600
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH METRIC:
- 70.00 MM
- MODEL:
- FORGED SERIES
- SKIRT COATING:
- NON-COATED
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- ATV
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- BORE SIZE METRIC:
- 86.00 MM
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- DISPLACEMENT:
- 397 CC
- PISTON DIAMETER METRIC:
- 85.95 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$210.95Qty in Cart: 0Quantity:Price:$210.95Subtotal: -
Wiseco Piston Honda CRF250R 2004-2007 4366M09750
WISECO
$239.95The Wiseco piston is engineered for riders who demand reliable power without compromise. A high-silicon aluminum alloy construction paired with an 11:1 compression ratio delivers measurable gains in combustion efficiency and throttle response. This...4366M09750- SKU:
- 4366M09750
- Availability:
- Ships Same Business Day
- Weight:
- 1.40 LBS
- PRODUCT NAME:
- PISTON KIT
- DISPLACEMENT:
- 591 CC
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- BORE SIZE METRIC:
- 97.50 MM
- MODEL:
- FORGED SERIES
- SKIRT COATING:
- NON-COATED
- UNITS:
- KIT
- BORE - OVERSIZE:
- +0,50 MM
- COMPRESSION RATIO IMPERIAL:
- 11.0:1
- PISTON DIAMETER METRIC:
- 97.42 MM
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 80.00 MM
$239.95Qty in Cart: 0Quantity:Price:$239.95Subtotal: -
Wiseco Piston Kit 1.00mm Oversize 57.00mm Yamaha YZ125 1976-1982 435M05700
WISECO
$154.95When your YZ125's original piston reaches its limits, a quality replacement isn't just a maintenance item—it's the foundation for reliable power and longevity. The Wiseco 435M05700 delivers the precision engineering and proven durability that serious...435M05700- SKU:
- 435M05700
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 123 CC
- MODEL:
- FORGED SERIES
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- NON-COATED
- BORE - OVERSIZE:
- +1,00 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 56.95 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 57.00 MM
- STROKE LENGTH METRIC:
- 50.00 MM
$154.95 -
HOT RODS Connecting Rod 8126
HOT RODS
$138.95If you're building or rebuilding an engine that sees sustained high-RPM operation, connecting rod integrity is non-negotiable—failure here means catastrophic engine damage. The HOT RODS 8126 is engineered specifically for that duty, combining premium...427308- SKU:
- 427308
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
- FEATURES:
- INCLUDES THRUST WASHERS
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- CONNECTING ROD KIT
- UNITS:
- KIT
- ENGINE TYPE:
- 2-CYCLE
- MATERIAL:
- 8620 STEEL
$138.95 -
HOT RODS Connecting Rod 8107
HOT RODS
$196.95Heavy-duty racing demands connecting rods that won't compromise under extreme RPM and combustion pressures. The HOT RODS 8107 delivers the strength and precision required for sustained high-performance operation, whether you're rebuilding a competition...427303- SKU:
- 427303
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- MATERIAL:
- 8620 STEEL
- PRODUCT NAME:
- CONNECTING ROD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 2-CYCLE
- FEATURES:
- INCLUDES THRUST WASHERS
$196.95 -
HOT RODS Connecting Rod 8106
HOT RODS
$135.95When you're pushing your engine to the limit, your connecting rods are working at the edge of mechanical failure—which is why settling for marginal components isn't an option. The HOT RODS 8106 is engineered to handle sustained high-RPM loads with the...427302- SKU:
- 427302
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- ENGINE TYPE:
- 2-CYCLE
- MATERIAL:
- 8620 STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- FEATURES:
- INCLUDES THRUST WASHERS
- PRODUCT NAME:
- CONNECTING ROD KIT
$135.95Qty in Cart: 0Quantity:Price:$135.95Subtotal: -
HOT RODS Connecting Rod 8127
HOT RODS
$123.95Whether you're building a competition engine or restoring a high-performance classic, connecting rods are the critical link between your crankshaft and pistons—and reliability at high RPM depends on precision engineering. The HOT RODS 8127 Connecting Rod...425505- SKU:
- 425505
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
- ENGINE TYPE:
- 2-CYCLE
- UNITS:
- KIT
- MATERIAL:
- 8620 STEEL
- FEATURES:
- INCLUDES THRUST WASHERS
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- CONNECTING ROD KIT
$123.95Qty in Cart: 0Quantity:Price:$123.95Subtotal: -
HOT RODS Connecting Rod 8105
HOT RODS
$158.95When you're pushing your engine to the limit, a stock connecting rod becomes your weakest link. The HOT RODS 8105 is engineered to handle sustained high-RPM loads without flex or failure, giving you the reliability to focus on performance rather than...425503- SKU:
- 425503
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- RIDING STYLE:
- OFF-ROAD
- FEATURES:
- INCLUDES THRUST WASHERS
- PRODUCT NAME:
- CONNECTING ROD KIT
- UNITS:
- KIT
- ENGINE TYPE:
- 2-CYCLE
- MATERIAL:
- 8620 STEEL
$158.95Qty in Cart: 0Quantity:Price:$158.95Subtotal: -
HOT RODS Connecting Rod 8110
HOT RODS
$141.95High-RPM engine builds demand connecting rods engineered for sustained power delivery and reliability under extreme loads. The HOT RODS 8110 replaces worn or failed OEM rods with certified 8620 AISI steel construction and precision bearing geometry...425502- SKU:
- 425502
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- FEATURES:
- INCLUDES THRUST WASHERS
- ENGINE TYPE:
- 2-CYCLE
- MATERIAL:
- 8620 STEEL
- PRODUCT NAME:
- CONNECTING ROD KIT
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
$141.95 -
HOT RODS Connecting Rod 8111
HOT RODS
$151.95If you're building or rebuilding a high-performance engine, your connecting rods need to survive extreme combustion pressures and RPM loads without failure. The HOT RODS 8111 combines proven OE-replacement geometry with metallurgical upgrades and...423301- SKU:
- 423301
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- MATERIAL:
- 8620 STEEL
- ENGINE TYPE:
- 2-CYCLE
- FEATURES:
- INCLUDES THRUST WASHERS
- PRODUCT NAME:
- CONNECTING ROD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$151.95
