Dirt Bike Piston and Ring Kits
Dirt Bike Piston & Ring Kits for Yamaha YZ85, WR250 & YZ250 at JJ Motorsports
Rebuild your dirt bike's top end for maximum power and reliability with premium piston and ring kits from JJ Motorsports, forged from high-strength aluminum for superior heat resistance, lightweight performance, and precise fit in motocross, enduro, and trail riding. Our selection includes complete kits with pistons, high-performance rings, wrist pins, circlips, top-end bearings, and gaskets designed for enhanced combustion efficiency, reduced blow-by, and longer engine life under high-RPM abuse. Compatible with popular models like Yamaha YZ85 (2002-2018), WR250, and YZ250, these Wiseco-engineered components feature CNC-machined crowns for optimal cam shape, ArmorGlide skirt coatings for low friction, and 4032 alloy construction for durability in dusty, aggressive conditions. Whether you're refreshing a youth 85cc 2-stroke or upgrading a 250cc big bore, these kits ensure crisp throttle response, better sealing, and race-ready power without the need for custom boring—perfect for DIY rebuilds or pro-level maintenance.
Shop trusted brands like Wiseco for race-proven quality. Explore related categories such as dirt bike engine for cylinders and valves or dirt bike air and fuel for carburetors and jets.
Top Dirt Bike Piston & Ring Kits
- Wiseco YZ85 2002-2018 Piston Kit with Gaskets PK1202 – 47.50mm forged aluminum piston kit for Yamaha YZ85 2-stroke; includes rings, wrist pin, circlips, bearing, and gaskets for enhanced combustion and throttle response.
- Wiseco 68.00mm Piston Kit with Gaskets Yamaha WR/YZ 250 PK1563 – Complete big bore kit for Yamaha WR250/YZ250; features forged piston, rings, wrist pin, circlips, and top-end gaskets for superior power and sealing.
Browse our in-stock inventory below with same-day shipping and expert support. Free shipping on orders over $99! Questions? Contact us for fitment advice!
- Product
- Qty in Cart
- Quantity
- Price
- Subtotal
-
WSM Piston Kit - Kawasaki - +1 mm 010-843-07K
WSM
$98.28Whether you're rebuilding a two-stroke engine or maximizing performance in a high-rpm application, piston quality directly impacts power delivery, reliability, and engine longevity. The WSM Piston Kit delivers OEM-equivalent construction with proven...09100651- SKU:
- 09100651
- Availability:
- Ships Same Business Day
- Weight:
- 1.20 LBS
- MODEL:
- ORIGINAL
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 82.00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
$98.28 -
WSM Piston Kit - Polaris - Standard 010-835K
WSM
$89.33Stock pistons wear down under sustained high-RPM operation, leading to blow-by, compression loss, and reduced power output. The WSM Piston Kit delivers OEM-equivalent quality with engineering refinements that enhance durability and thermal management,...09100655- SKU:
- 09100655
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 84.00 MM
- MODEL:
- ORIGINAL
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- RIDING STYLE:
- WATERCRAFT
$89.33 -
WSM Piston Kit - Polaris - +.5 mm 010-835-05K
WSM
$89.33When your engine is pushing hard, piston quality becomes non-negotiable. The WSM Piston Kit delivers OEM-equivalent construction with measurable performance gains through advanced materials and precision engineering—ensuring reliability under sustained...09100656- SKU:
- 09100656
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- BORE - OVERSIZE METRIC:
- +0.50 MM
- RIDING STYLE:
- WATERCRAFT
- BORE - OVERSIZE:
- +0,50 MM
- BORE SIZE METRIC:
- 84.00 MM
- MODEL:
- ORIGINAL
- PISTON MATERIAL:
- ALUMINUM
- UNITS:
- KIT
- PRODUCT NAME:
- PISTON KIT
$89.33 -
WSM Piston Kit - Polaris - +1 mm 010-835-07K
WSM
$89.33When you're pushing your Polaris to the limit, stock pistons become your bottleneck—they're simply not engineered for sustained high-performance demands. The WSM Piston Kit delivers OEM-equivalent quality with critical performance upgrades: a proprietary...09100657- SKU:
- 09100657
- Availability:
- Ships Same Business Day
- Weight:
- 1.32 LBS
- MODEL:
- ORIGINAL
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- BORE SIZE METRIC:
- 84.00 MM
- PISTON MATERIAL:
- ALUMINUM
- UNITS:
- KIT
- RIDING STYLE:
- WATERCRAFT
- PRODUCT NAME:
- PISTON KIT
$89.33 -
WSM Piston Kit - Yamaha - Standard 010-827K
WSM
$80.40A piston kit is only as good as its ability to withstand extreme combustion pressures while maintaining thermal efficiency—and the WSM Piston Kit delivers on both fronts. The MOS2 coating on the skirts actively dissipates heat while reducing friction,...09100659- SKU:
- 09100659
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
- BORE SIZE METRIC:
- 81.00 MM
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- ORIGINAL
$80.40 -
WSM Piston Kit - Yamaha - +.5 mm 010-827-05K
WSM
$80.40A worn or damaged piston directly limits your engine's ability to produce consistent power and can lead to catastrophic failure if left unchecked. The WSM Piston Kit delivers OEM-equivalent quality with engineered improvements—particularly the enhanced...09100660- SKU:
- 09100660
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- BORE - OVERSIZE:
- +0,50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
- BORE SIZE METRIC:
- 81.00 MM
- MODEL:
- ORIGINAL
- PRODUCT NAME:
- PISTON KIT
$80.40 -
WSM Piston Kit - Yamaha - +1 mm 010-827-07K
WSM
$80.40If you're rebuilding a Yamaha engine or pushing higher compression ratios, piston quality directly impacts reliability, power output, and engine longevity. The WSM +1mm 010-827-07K kit delivers OEM-equivalent construction with factory-proven geometry,...09100661- SKU:
- 09100661
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 81.00 MM
- MODEL:
- ORIGINAL
$80.40 -
WSM Piston Assembly - Sea-Doo - +.5 mm 010-861-05PK
WSM
$133.96OEM-quality pistons are the foundation of reliable engine performance, and this WSM assembly delivers durability without compromise. The advanced MOS2 coating reduces friction and heat while actively drawing thermal energy away from critical ring...09101273- SKU:
- 09101273
- Availability:
- Ships Same Business Day
- Weight:
- 1.45 LBS
- BORE - OVERSIZE:
- +0,50 MM
- BORE SIZE METRIC:
- 99.96 MM
- PISTON MATERIAL:
- ALUMINUM
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +0.50 MM
- RIDING STYLE:
- WATERCRAFT
- MODEL:
- PLATINUM
- PRODUCT NAME:
- PISTON KIT
$133.96 -
VERTEX Piston Kit VTK22813CD
VERTEX
$125.95Precision-engineered pistons are the foundation of reliable high-RPM performance, and the VERTEX Piston Kit VTK22813CD delivers the durability and consistency your engine demands. Built with industry-leading heat treatment and a proven Molybdenum...09103115- SKU:
- 09103115
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- DISPLACEMENT:
- 50 CC
- PISTON DIAMETER METRIC:
- 39.47 MM
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PRODUCT NAME:
- TOP END PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- ENGINE TYPE:
- 2-STROKE
- CYLINDER DIAMETER METRIC:
- 39.50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$125.95 -
VERTEX Piston Kit VTK23429CD
VERTEX
$137.95If you're building an engine that needs to survive sustained RPMs and aggressive combustion pressures, piston quality directly impacts reliability and longevity. The VERTEX Piston Kit VTK23429CD delivers the heat treatment and surface engineering that...09103116- SKU:
- 09103116
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- CYLINDER DIAMETER METRIC:
- 39.50 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PISTON DIAMETER METRIC:
- 39.47 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- DISPLACEMENT:
- 50 CC
- PRODUCT NAME:
- TOP END PISTON KIT
$137.95 -
VERTEX Piston Kit VTK22481CD
VERTEX
$150.95Precision-engineered pistons are the foundation of reliable high-RPM performance, and the VERTEX Piston Kit VTK22481CD delivers the durability and longevity your engine demands. Built with advanced heat treatment and a specialized skirt coating, these...09103117- SKU:
- 09103117
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- CYLINDER DIAMETER METRIC:
- 45.00 MM
- DISPLACEMENT:
- 65 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 44.97 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- CAST REPLICA
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- TOP END PISTON KIT
- UNITS:
- KIT
$150.95 -
VERTEX Piston Kit VTK23430CD
VERTEX
$137.95A quality piston kit is the foundation of reliable high-rpm performance, and the VERTEX VTK23430CD delivers the durability and precision demanded by serious racers and build enthusiasts. The T-5 heat treatment and molybdenum disulfide coating work...09103118- SKU:
- 09103118
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 45.00 MM
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- PISTON DIAMETER METRIC:
- 44.97 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- DISPLACEMENT:
- 65 CC
- PRODUCT NAME:
- TOP END PISTON KIT
$137.95 -
VERTEX Piston Kit VTK22998B
VERTEX
$223.95Maximum piston durability and reliable performance depend on heat treatment and surface protection—two areas where VERTEX VTK22998B excels. The T-5 hardening and tempering cycle ensures your pistons withstand extreme combustion pressures and temperature...09103120- SKU:
- 09103120
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.00 MM
- PRODUCT NAME:
- TOP END PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- DISPLACEMENT:
- 125 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 53.96 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$223.95 -
VERTEX Piston Kit VTK22854B-1
VERTEX
$262.95When you're pushing your engine to the limit, stock pistons simply won't cut it. The VERTEX Piston Kit VTK22854B-1 delivers the durability and precision engineering needed for sustained high-performance operation, with advanced heat-treatment and...09103121- SKU:
- 09103121
- Availability:
- Ships Same Business Day
- Weight:
- 1.30 LBS
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PRODUCT NAME:
- TOP END PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- PISTON DIAMETER METRIC:
- 66.35 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$262.95Qty in Cart: 0Quantity:Price:$262.95Subtotal: -
VERTEX Piston Kit VTK22854B
VERTEX
$262.95OEM pistons wear out—VERTEX pistons are engineered to last. The VTK22854B kit delivers the durability and precision fit your engine demands, with advanced coatings and heat treatment that reduce friction during break-in and extend service life. Whether...09103122- SKU:
- 09103122
- Availability:
- Ships Same Business Day
- Weight:
- 1.50 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 66.35 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- CAST REPLICA
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- DISPLACEMENT:
- 250 CC
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- TOP END PISTON KIT
- UNITS:
- KIT
$262.95 -
VERTEX Piston Kit 23614050
VERTEX
$170.95Engine reliability and performance depend on precision-engineered pistons that can withstand extreme combustion pressures while maintaining tight tolerances. The VERTEX Piston Kit 23614050 delivers the durability and strength required for both stock...09102050- SKU:
- 09102050
- Availability:
- Ships Same Business Day
- Weight:
- 0.42 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 53.00 MM
- STYLE:
- CAST REPLICA
- DISPLACEMENT:
- 100 CC
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- PISTON DIAMETER METRIC:
- 52.95 MM
$170.95 -
VERTEX Piston Kit 23614200
VERTEX
$177.95Whether you're rebuilding a two-stroke for peak performance or upgrading your four-stroke engine, the VERTEX Piston Kit 23614200 delivers the precision engineering and durability you need to maximize power and reliability. VERTEX pistons are heat-treated...09102051- SKU:
- 09102051
- Availability:
- Ships Same Business Day
- Weight:
- 0.44 LBS
- DISPLACEMENT:
- 107 CC
- PISTON DIAMETER METRIC:
- 54.45 MM
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +2.00 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.50 MM
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST BIG BORE
- BORE - OVERSIZE:
- +2,00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$177.95Qty in Cart: 0Quantity:Price:$177.95Subtotal: -
VERTEX Piston Kit 23621200
VERTEX
$188.95A quality piston kit is fundamental to engine reliability and performance—especially under high RPM and forced induction scenarios. The VERTEX Piston Kit 23621200 delivers OEM-grade construction with durability enhancements that reduce wear during...09102054- SKU:
- 09102054
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- DISPLACEMENT:
- 100 CC
- PISTON DIAMETER METRIC:
- 54.45 MM
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.50 MM
- STYLE:
- CAST REPLICA
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$188.95 -
VERTEX Piston Kit 23646B
VERTEX
$256.95Whether you're rebuilding after a complete teardown or upgrading to forged internals for higher compression, the VERTEX Piston Kit 23646B delivers the durability and precision you need to push your engine harder. The molybdenum disulfide-coated skirts...09102056- SKU:
- 09102056
- Availability:
- Ships Same Business Day
- Weight:
- 0.54 LBS
$256.95 -
VERTEX Piston Kit - Standard 22863B
VERTEX
$116.95Precision-engineered pistons are the foundation of reliable high-RPM performance, and the VERTEX 22863B delivers the durability demanded by serious racers and rebuild specialists. The T-5 heat treatment cycle ensures superior hardness and fatigue...09101024- SKU:
- 09101024
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
- CYLINDER DIAMETER METRIC:
- 47.50 MM
- PRODUCT NAME:
- PISTON KIT
- ENGINE TYPE:
- 2-STROKE
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PISTON MATERIAL:
- CAST
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 85 CC
- PISTON DIAMETER METRIC:
- 47.45 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- CAST REPLICA
$116.95
