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 Kawasaki KX100 2014-2021 880M05250
WISECO
$138.95Your KX100's factory piston won't cut it if you're pushing harder on the track or trail. The Wiseco 880M05250 Pro-Lite delivers measurable gains in compression efficiency and engine durability...09103965- SKU:
- 09103965
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 52.50 MM
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 99 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- STROKE LENGTH METRIC:
- 45.80 MM
$138.95 -
Wiseco Piston Kit Kawasaki KX450F 2013-2018 12.5:1 Compression 40082M09600
WISECO
$255.95If you're running a KX450F at the edge of its limits, a worn or stock piston limits your engine's potential for power and reliability. The Wiseco 40082M09600 delivers a 12.5:1 compression ratio that...09103172- SKU:
- 09103172
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- BORE - OVERSIZE:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 12.5:1
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 62.10 MM
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE SIZE METRIC:
- 96.00 MM
- DISPLACEMENT:
- 449 CC
$255.95 -
Wiseco Piston Kit Racer Elite 96mm 14:1 Compression Honda TRX450R 2006-2009 RE817M09600
WISECO
$388.95If you're running a Honda TRX450R or TRX450ER, this piston kit delivers the compression ratio and durability you need to extract real power gains without compromising reliability. The 14:1...09105126- SKU:
- 09105126
- Availability:
- Ships Same Business Day
- Weight:
- 1.06 LBS
- BORE SIZE METRIC:
- 96.00 MM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE METRIC:
- STANDARD
- SKIRT COATING:
- ARMORGLIDE®
- UNITS:
- KIT
- BORE - OVERSIZE:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 14.0:1
- RIDING STYLE:
- ATV
$388.95 -
Wiseco Piston Kit Yamaha YZ65 2018-2026 43.5mm 885M04350
WISECO
$127.95The Wiseco 885M04350 piston kit is engineered to deliver the durability and precision your YZ65 demands, whether you're racing competitively or pushing hard on the trail. Stock pistons wear quickly...09105380- SKU:
- 09105380
- Availability:
- Ships Same Business Day
- Weight:
- 0.31 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 43.50 MM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$127.95 -
Wiseco Piston Kit 50mm 2002-2020 Suzuki RM85 RE901M05000
WISECO
$134.95The Wiseco RE901M05000 Racer Elite piston kit is engineered to deliver the durability and precision your Suzuki RM85 demands, whether you're pushing lap times or tackling demanding terrain. Factory...09105108- SKU:
- 09105108
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE:
- +2,00 MM
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- BORE - OVERSIZE METRIC:
- +2.00 MM
- BORE SIZE METRIC:
- 50.00 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- UNITS:
- KIT
$134.95 -
Wiseco Piston Kit 53mm for 2002-2009 Suzuki RM85 RE901M05300
WISECO
$169.95Stock pistons in the RM85 platform wear quickly under competitive riding conditions, robbing you of compression and throttle response. The Wiseco RE901M05300 Racer Elite kit delivers OEM-grade...09105110- SKU:
- 09105110
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- BORE SIZE METRIC:
- 53.00 MM
- PISTON MATERIAL:
- FORGED
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- BORE - OVERSIZE:
- +5,00 MM
- BORE - OVERSIZE METRIC:
- +5.00 MM
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- UNITS:
- KIT
$169.95Qty in Cart: 0Quantity:Price:$169.95Subtotal: -
Wiseco RM125 2004-2007 Piston Kit RE914M05400
WISECO
$204.95The Wiseco RE914M05400 Racer Elite piston kit delivers the compression, durability, and throttle response your RM125 demands during competition or high-intensity riding. With ArmorPlating detonation...09105111- SKU:
- 09105111
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- BORE SIZE METRIC:
- 54.00 MM
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- UNITS:
- KIT
$204.95Qty in Cart: 0Quantity:Price:$204.95Subtotal: -
Wiseco Suzuki RM125 2004-2007 56mm Piston Kit RE914M05600
WISECO
$204.95If you're running a Suzuki RM125 at the edge of its limits, you need a piston kit engineered to handle the punishment. The Wiseco RE914M05600 Racer Elite delivers the compression, durability, and...09105112- SKU:
- 09105112
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE:
- +2,00 MM
- BORE SIZE METRIC:
- 56.00 MM
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- BORE - OVERSIZE METRIC:
- +2.00 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- UNITS:
- KIT
$204.95Qty in Cart: 0Quantity:Price:$204.95Subtotal: -
Wiseco Piston Kit Yamaha YZ85 2002-2021 47.50mm RE900M04750
WISECO
$171.95The Wiseco Piston Kit is engineered for the Yamaha YZ85 to deliver the durability and sealing performance required in high-demand 2-stroke racing environments. Whether you're rebuilding after a...09105116- SKU:
- 09105116
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 47.50 MM
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
$171.95Qty in Cart: 0Quantity:Price:$171.95Subtotal: -
Wiseco 2-Stroke Piston Kit 48mm Oversize Yamaha YZ85 2002-2025 RE900M04800
WISECO
$134.95The Wiseco RE900M04800 is purpose-built for YZ85 racers who demand reliability when it matters most. Whether you're chasing podiums or rebuilding after hard use, this 48mm oversize piston kit...09105117- SKU:
- 09105117
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- BORE - OVERSIZE METRIC:
- +0.50 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- BORE - OVERSIZE:
- +0,50 MM
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- UNITS:
- KIT
- BORE SIZE METRIC:
- 48.00 MM
- PISTON MATERIAL:
- FORGED
$134.95Qty in Cart: 0Quantity:Price:$134.95Subtotal: -
Wiseco Piston Kit 54mm Yamaha YZ125 2005-2024 RE905M05400
WISECO
$221.95The Wiseco Piston Kit RE905M05400 delivers the reliability and power output that YZ125 racers demand. Built from premium 2000 Series forged alloy, this piston withstands the extreme combustion...09105120- SKU:
- 09105120
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- UNITS:
- KIT
- BORE SIZE METRIC:
- 54.00 MM
$221.95 -
Wiseco YZ125 2005-2020 Racer Elite Piston Kit RE905M05600
WISECO
$204.95The YZ125 demands a piston that can handle sustained high RPM racing without compromise. Wiseco's Racer Elite kit delivers the precision fitment and durability required for consistent top-end...09105121- SKU:
- 09105121
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- BORE - OVERSIZE:
- +2,00 MM
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE METRIC:
- +2.00 MM
- BORE SIZE METRIC:
- 56.00 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- UNITS:
- KIT
$204.95 -
Wiseco Piston Kit Racer Elite Yamaha YZ125 2005-2021 RE906M05800
WISECO
$204.95A worn or damaged piston directly impacts combustion efficiency, throttle response, and engine longevity—especially in high-rpm 2-stroke applications like the YZ125. The Wiseco Racer Elite kit...09105122- SKU:
- 09105122
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- BORE SIZE METRIC:
- 48.00 MM
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE METRIC:
- +4.00 MM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- BORE - OVERSIZE:
- +4,00 MM
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- UNITS:
- KIT
$204.95Qty in Cart: 0Quantity:Price:$204.95Subtotal: -
Wiseco YZ250 1999-2024 Racer Elite Piston Kit 66.40mm RE902M06640
WISECO
$249.95The piston is the powerhouse of your 2-stroke engine—it's where combustion converts to acceleration. A worn or undersized piston kills compression, throttle response, and overall performance. The...09105123- SKU:
- 09105123
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- ARMORFIT™
- PISTON MATERIAL:
- 2000 SERIES ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- RACER ELITE
- UNITS:
- KIT
- BORE SIZE METRIC:
- 66.40 MM
$249.95Qty in Cart: 0Quantity:Price:$249.95Subtotal: -
Wiseco Piston Kit with Gaskets for 2003 Suzuki RM100 PK1155
WISECO
$179.95A worn top-end can quietly rob your RM100 of power and responsiveness. The Wiseco PK1155 restores lost compression and combustion efficiency with aerospace-grade forged aluminum pistons machined to...09030181- SKU:
- 09030181
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- BORE SIZE METRIC:
- 53.00 MM
- DISPLACEMENT:
- 99 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- +0.50 MM
- MODEL:
- PRO-LITE
- PISTON DIAMETER METRIC:
- 52.95 MM
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- BORE - OVERSIZE:
- +0,50 MM
- SKIRT COATING:
- NON-COATED
- STROKE LENGTH METRIC:
- 45.80 MM
- UNITS:
- KIT
$179.95Qty in Cart: 0Quantity:Price:$179.95Subtotal: -
Wiseco Honda CR85R 2003-2007 Piston Kit with Gaskets PK1218
WISECO
$184.95A worn or damaged piston directly compromises your CR85R's compression, throttle response, and overall reliability—especially critical in competitive or high-demand riding. The Wiseco PK1218 restores...09030183- SKU:
- 09030183
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- BORE - OVERSIZE METRIC:
- +3.00 MM
- BORE SIZE METRIC:
- 50.50 MM
- PRODUCT NAME:
- REBUILD KIT
- BORE - OVERSIZE:
- +3,00 MM
- DISPLACEMENT:
- 84.7 CC
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- ENGINE TYPE:
- 2-STROKE
- SKIRT COATING:
- NON-COATED
- MODEL:
- PRO-LITE
- PISTON DIAMETER METRIC:
- 50.45 MM
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 47.80 MM
- TYPE:
- TOP END
- UNITS:
- KIT
$184.95Qty in Cart: 0Quantity:Price:$184.95Subtotal: -
Wiseco Piston Kit for Honda XR250R 1986-2004 74mm 10.5:1 Compression PK1221
WISECO
$257.95The stock piston in your XR250R will eventually show signs of wear—especially if you're pushing the engine hard or running higher octane fuel for increased performance. The Wiseco PK1221 restores...09030193- SKU:
- 09030193
- Availability:
- Ships Same Business Day
- Weight:
- 1.25 LBS
- BORE SIZE METRIC:
- 74.00 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON DIAMETER METRIC:
- 73.95 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- 10.5:1
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- PRODUCT NAME:
- REBUILD KIT
- STROKE LENGTH METRIC:
- 59.50 MM
- TYPE:
- TOP END
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 250 CC
- MODEL:
- FORGED SERIES
- SKIRT COATING:
- NON-COATED
$257.95Qty in Cart: 0Quantity:Price:$257.95Subtotal: -
Wiseco Honda XR200R 1992-2002 66.5mm Piston Kit with Gaskets PK1126
WISECO
$204.95The Wiseco PK1126 Piston Kit is engineered for riders who demand reliability and measurable performance gains from their Honda XR200R. Whether you're rebuilding after high-mileage wear or upgrading...09030201- SKU:
- 09030201
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- BORE - OVERSIZE:
- +1,00 MM
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- MODEL:
- FORGED SERIES
- PRODUCT NAME:
- REBUILD KIT
- BORE - OVERSIZE METRIC:
- +1.00 MM
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- NON-COATED
- UNITS:
- KIT
- PISTON MATERIAL:
- 2618 ALUMINUM ALLOY
- STROKE LENGTH METRIC:
- 57.80 MM
- BORE SIZE METRIC:
- 66.50 MM
- DISPLACEMENT:
- 192 CC
- PISTON DIAMETER METRIC:
- 66.45 MM
- TYPE:
- TOP END
$204.95Qty in Cart: 0Quantity:Price:$204.95Subtotal: -
Wiseco Honda CR250R 1997-2001 Piston Kit with Gaskets 67.50mm PK1170
WISECO
$259.95If you're rebuilding the top end of a 1997-2001 Honda CR250R, you need a piston kit engineered to withstand the demands of two-stroke racing. The Wiseco PK1170 delivers the compression consistency...09030208- SKU:
- 09030208
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- MODEL:
- PRO-LITE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +1.10 MM
- BORE SIZE METRIC:
- 67.50 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 67.46 MM
- SKIRT COATING:
- NON-COATED
- BORE - OVERSIZE:
- +1,10 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- STROKE LENGTH METRIC:
- 72.00 MM
- DISPLACEMENT:
- 249 CC
- PRODUCT NAME:
- REBUILD KIT
$259.95Qty in Cart: 0Quantity:Price:$259.95Subtotal: -
Wiseco Yamaha PW50 1981-2020 Piston Kit 41mm PK1161
WISECO
$149.95A worn top-end can rob your PW50 of power and reliability—the Wiseco PK1161 gives you a straightforward path back to peak performance. This complete piston kit delivers the precision machining and...09030269- SKU:
- 09030269
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- UNITS:
- EACH
- BORE SIZE METRIC:
- 41.00 MM
- MODEL:
- RACER'S CHOICE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- COOLING SYSTEM:
- AIR COOLED
- DISPLACEMENT:
- 49 CC
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 39.20 MM
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- ALUMINUM
$149.95Qty in Cart: 0Quantity:Price:$149.95Subtotal:
