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
-
JE PISTONS Piston Kit 325027
JE PISTONS
$329.99When you're pushing your engine to the absolute limit—whether on the track or in competition—your pistons need to withstand extreme combustion pressures and temperatures without compromise. JE...09105941- SKU:
- 09105941
- Availability:
- Ships Same Business Day
- Weight:
- 1.36 LBS
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- WALL THICKNESS IMPERIAL:
- 0.160'
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- ATV
- WALL THICKNESS:
- 0,160'
- BORE SIZE METRIC:
- 99.00 MM
- DISPLACEMENT:
- 477 CC
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
$329.99Qty in Cart: 0Quantity:Price:$329.99Subtotal: -
JE PISTONS Piston Kit 345054
JE PISTONS
$446.99When you're pushing your engine to the absolute limit—whether on the track or in competition—factory pistons simply won't cut it. JE PISTONS' 345054 kit delivers the strength, precision, and weight...09105943- SKU:
- 09105943
- Availability:
- Ships Same Business Day
- Weight:
- 1.36 LBS
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- PRO SERIES
- UNITS:
- KIT
- PISTON HEAD SHAPE:
- DOMED
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 96.00 MM
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- DISPLACEMENT:
- 449 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
$446.99 -
JE PISTONS Piston Kit 345056
JE PISTONS
$446.99When you're pushing your engine to the absolute limit in competition, your pistons need to survive extreme pressures and temperatures without compromise. JE PISTONS' Pro Series 345056 kit delivers...09105945- SKU:
- 09105945
- Availability:
- Ships Same Business Day
- Weight:
- 1.01 LBS
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- PRO SERIES
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 14.5:1
- PISTON HEAD SHAPE:
- DOMED
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE SIZE METRIC:
- 96.00 MM
- DISPLACEMENT:
- 449 CC
- PRODUCT NAME:
- PISTON KIT
$446.99 -
JE PISTONS Piston Kit 345193
JE PISTONS
$839.99If you're running a high-displacement or boosted engine in a competition setting, you need pistons engineered to handle extreme pressure and heat cycles without compromise. JE PISTONS' Pro Series...09105947- SKU:
- 09105947
- Availability:
- Ships Same Business Day
- Weight:
- 2.66 LBS
- DISPLACEMENT:
- 998 CC
- UNITS:
- KIT
- BORE SIZE METRIC:
- 80.00 MM
- COMPRESSION RATIO IMPERIAL:
- 11.5:1
- PRODUCT NAME:
- PISTON KIT
- WALL THICKNESS:
- 0,160'
- WALL THICKNESS IMPERIAL:
- 0.160'
- PISTON HEAD SHAPE:
- DOMED
- RIDING STYLE:
- UTV
$839.99 -
JE PISTONS Piston Kit 345200
JE PISTONS
$424.99When you're pushing your engine to its limits in competition, your pistons need to withstand extreme pressures and temperatures without compromise. JE PISTONS' Pro Series 345200 kit delivers the...09105948- SKU:
- 09105948
- Availability:
- Ships Same Business Day
- Weight:
- 0.76 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 77.00 MM
- PRODUCT NAME:
- PISTON KIT
- STYLE:
- PRO SERIES
- RIDING STYLE:
- OFF-ROAD
- COMPRESSION RATIO IMPERIAL:
- 14.0:1
- PISTON HEAD SHAPE:
- DOMED
- TYPE:
- FORGED SIDE RELIEF DESIGN
- UNITS:
- KIT
$424.99 -
JE PISTONS Piston Kit 345055
JE PISTONS
$446.99When you're pushing an engine to its absolute limits, stock pistons won't cut it. JE PISTONS 345055 Pro Series pistons are purpose-built for extreme competition applications, delivering the precision...09105944- SKU:
- 09105944
- Availability:
- Ships Same Business Day
- Weight:
- 1.11 LBS
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- PRO SERIES
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 14.0:1
- DISPLACEMENT:
- 449 CC
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- BORE SIZE METRIC:
- 96.00 MM
- PRODUCT NAME:
- PISTON KIT
$446.99 -
JE PISTONS Piston Kit 130798
JE PISTONS
$269.99When you're pushing your engine to its limits in competition, factory pistons simply won't cut it. JE PISTONS' Pro Series kit delivers the precision engineering and material science required to...09105835- SKU:
- 09105835
- Availability:
- Ships Same Business Day
- Weight:
- 1.31 LBS
- DISPLACEMENT:
- 540 CC
- PISTON HEAD SHAPE:
- DOMED
- TYPE:
- ROUND FORGED DESIGN
- BORE - OVERSIZE METRIC:
- +3.00 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- STYLE:
- JE PISTON
- BORE - OVERSIZE:
- +3,00 MM
- BORE SIZE METRIC:
- 90.00 MM
- COMPRESSION RATIO IMPERIAL:
- 11.0:1
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$269.99Qty in Cart: 0Quantity:Price:$269.99Subtotal: -
On Sale
PROX Piston - GP 760 Waverunner 01.2514.050
PROX
MSRP: $138.95Now: $110.00Was: $138.95Piston for watercraft applications09102745- SKU:
- 09102745
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- BORE SIZE METRIC:
- 84.50 MM
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- EACH
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
MSRP: $138.95Now: $110.00Was: $138.95 -
On Sale
PROX Piston - GP 760 Waverunner 01.2514.100
PROX
MSRP: $129.95Now: $110.00Was: $129.95Piston for watercraft applications09102747- SKU:
- 09102747
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- WATERCRAFT
- PISTON MATERIAL:
- ALUMINUM
- ENGINE TYPE:
- 2-STROKE
- UNITS:
- EACH
- BORE SIZE METRIC:
- 85.00 MM
MSRP: $129.95Now: $110.00Was: $129.95Qty in Cart: 0Quantity:Price:MSRP: $129.95Now: $110.00Was: $129.95Subtotal: -
On Sale
PROX Piston Kit - KTM300EXC '17-'18 01.6387.B
PROX
MSRP: $189.95Now: $161.00Was: $189.95When your KTM 300 EXC demands peak performance and reliability, OEM-spec pistons are non-negotiable. The PROX Piston Kit delivers factory-equivalent durability with precision Japanese engineering,...09106265- SKU:
- 09106265
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- PISTON KIT
MSRP: $189.95Now: $161.00Was: $189.95Qty in Cart: 0Quantity:Price:MSRP: $189.95Now: $161.00Was: $189.95Subtotal: -
VERTEX Piston Kit 23870B
VERTEX
$353.95A piston kit is the foundation of engine reliability and performance—whether you're rebuilding after wear or upgrading for increased displacement and power. The VERTEX Piston Kit 23870B delivers the...09103338- SKU:
- 09103338
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- FORGED HIGH COMPRESSION
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- 14.5:1
- CYLINDER DIAMETER METRIC:
- 78.00 MM
- DISPLACEMENT:
- 250 CC
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- PISTON DIAMETER METRIC:
- 77.97 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$353.95 -
VERTEX Piston Kit 23925B
VERTEX
$289.95If you're building or rebuilding an engine for serious duty—whether on the track or in competition—piston quality directly impacts reliability and performance longevity. The VERTEX Piston Kit 23925B...09103341- SKU:
- 09103341
- Availability:
- Ships Same Business Day
- Weight:
- 0.58 LBS
- CYLINDER DIAMETER METRIC:
- 80.00 MM
- BORE - OVERSIZE:
- +3,00 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- STYLE:
- FORGED BIG BORE
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- ENGINE TYPE:
- 4-STROKE
- BORE - OVERSIZE METRIC:
- +3.00 MM
- DISPLACEMENT:
- 270 CC
- PISTON DIAMETER METRIC:
- 79.96 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
$289.95Qty in Cart: 0Quantity:Price:$289.95Subtotal: -
VERTEX Piston Kit 23119100
VERTEX
$170.95Whether you're rebuilding a worn top end or upgrading to higher compression, the VERTEX Piston Kit 23119100 delivers the durability and performance you need to stay competitive. VERTEX pistons...09103343- SKU:
- 09103343
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST BIG BORE
- DISPLACEMENT:
- 130 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- CYLINDER DIAMETER METRIC:
- 55.00 MM
- PISTON DIAMETER METRIC:
- 54.95 MM
$170.95Qty in Cart: 0Quantity:Price:$170.95Subtotal: -
VERTEX Piston Kit 23941A
VERTEX
$230.95A quality piston kit is fundamental to engine reliability and performance, especially under high-load conditions. The VERTEX Piston Kit 23941A delivers durability through advanced heat treatment and...09103345- SKU:
- 09103345
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
$230.95 -
VERTEX Piston Kit with Gaskets VTK22521B
VERTEX
$289.95If you're serious about extracting maximum power and reliability from your engine, pistons are where precision matters most. The VERTEX Piston Kit delivers forged high-compression geometry that...09103362- SKU:
- 09103362
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- PRODUCT NAME:
- TOP END PISTON KIT
- STYLE:
- CAST REPLICA
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 66.36 MM
- PISTON MATERIAL:
- CAST
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$289.95 -
VERTEX Piston Kit with Gaskets VTK22652B
VERTEX
$223.95Whether you're rebuilding a high-mileage engine or upgrading to a higher-compression setup, the VERTEX Piston Kit VTK22652B delivers the durability and performance you need for reliable power gains...09103375- SKU:
- 09103375
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- TOP END PISTON KIT
- DISPLACEMENT:
- 125 CC
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.00 MM
- PISTON DIAMETER METRIC:
- 53.96 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- STYLE:
- CAST REPLICA
$223.95 -
VERTEX Piston Kit with Gaskets VTK22806B
VERTEX
$208.95A piston kit is foundational to engine reliability and performance—this VERTEX kit delivers the precision engineering and durability required for sustained high-RPM operation. The T-5 heat treatment...09103380- SKU:
- 09103380
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- DISPLACEMENT:
- 125 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- ENGINE TYPE:
- 2-STROKE
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.00 MM
- PRODUCT NAME:
- TOP END PISTON KIT
- STYLE:
- CAST REPLICA
- PISTON DIAMETER METRIC:
- 53.94 MM
- PISTON MATERIAL:
- CAST
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$208.95 -
VERTEX Piston Kit VTK23124B
VERTEX
$289.95Precision-engineered pistons are the heart of any high-performance engine build, and the VERTEX Piston Kit VTK23124B delivers the durability and reliability demanded by serious racers and performance...09103074- SKU:
- 09103074
- Availability:
- Ships Same Business Day
- Weight:
- 1.30 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- PISTON DIAMETER METRIC:
- 66.36 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- DISPLACEMENT:
- 250 CC
- PRODUCT NAME:
- TOP END PISTON KIT
$289.95 -
VERTEX Piston Kit VTK22860B
VERTEX
$184.95The VERTEX Piston Kit VTK22860B delivers the precision and durability required for high-RPM engine builds. Purpose-engineered with heat-treated construction and a molybdenum disulfide coating, these...09103081- SKU:
- 09103081
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 44.50 MM
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- CAST
- DISPLACEMENT:
- 65 CC
- PISTON DIAMETER METRIC:
- 44.45 MM
- PRODUCT NAME:
- TOP END PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$184.95Qty in Cart: 0Quantity:Price:$184.95Subtotal: -
VERTEX Piston Kit VTK22803B
VERTEX
$184.95A quality piston kit is fundamental to engine reliability and performance—especially under high RPM and boost conditions. The VERTEX Piston Kit VTK22803B combines precision engineering with proven...09103082- SKU:
- 09103082
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- DISPLACEMENT:
- 85 CC
- STYLE:
- CAST REPLICA
- PISTON DIAMETER METRIC:
- 48.45 MM
- PRODUCT NAME:
- TOP END PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- CYLINDER DIAMETER METRIC:
- 48.50 MM
$184.95
