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 274191
JE PISTONS
$524.99When you're pushing your engine to its limits in competition, piston failure isn't an option—it's a catastrophe. JE PISTONS' 274191 Kit delivers the structural integrity and precision engineering...09105882- SKU:
- 09105882
- Availability:
- Ships Same Business Day
- Weight:
- 2.26 LBS
- RIDING STYLE:
- ATV
- UNITS:
- KIT
- WALL THICKNESS IMPERIAL:
- 0.140'
- RIDING STYLE:
- UTV
- WALL THICKNESS:
- 0,140'
- DISPLACEMENT:
- 749 CC
- PISTON HEAD SHAPE:
- DOMED
- BORE SIZE METRIC:
- 85.00 MM
- COMPRESSION RATIO IMPERIAL:
- 11.5:1
- PRODUCT NAME:
- PISTON KIT
$524.99 -
JE PISTONS Piston Kit 284766
JE PISTONS
$329.99When you're pushing your engine to the limit in competition, your pistons need to withstand extreme pressures and temperatures without compromise. JE PISTONS' Pro Series 284766 kit delivers the...09105897- SKU:
- 09105897
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- WALL THICKNESS:
- 0,150'
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- ATV
- COMPRESSION RATIO IMPERIAL:
- 11.0:1
- UNITS:
- KIT
- BORE SIZE METRIC:
- 105.50 MM
- DISPLACEMENT:
- 735 CC
- PISTON HEAD SHAPE:
- DOMED
- WALL THICKNESS IMPERIAL:
- 0.150'
$329.99 -
JE PISTONS Piston Kit 284767
JE PISTONS
$329.99When you're pushing your engine to the limit in competition, stock pistons won't cut it—you need forged aluminum built for extreme loads and sustained high RPM. JE PISTONS' Pro Series 284767 kit...09105898- SKU:
- 09105898
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- RIDING STYLE:
- ATV
- WALL THICKNESS:
- 0,150'
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- 12.5:1
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 105.50 MM
- DISPLACEMENT:
- 735 CC
- PISTON HEAD SHAPE:
- DOMED
- WALL THICKNESS IMPERIAL:
- 0.150'
$329.99 -
JE PISTONS Piston Kit 284852
JE PISTONS
$309.99When you're pushing your engine to the absolute limit in competition or extreme duty applications, your pistons need to withstand tremendous forces without compromise. JE PISTONS' Pro Series 284852...09105899- SKU:
- 09105899
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- STYLE:
- JE PISTON
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 12.8:1
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- BORE SIZE METRIC:
- 96.00 MM
- DISPLACEMENT:
- 449 CC
- PRODUCT NAME:
- PISTON KIT
$309.99Qty in Cart: 0Quantity:Price:$309.99Subtotal: -
JE PISTONS Piston Kit 284853
JE PISTONS
$309.99If you're building an engine for professional competition or extreme performance demands, you need pistons engineered to survive conditions that standard parts simply cannot handle. JE PISTONS' Pro...09105900- SKU:
- 09105900
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- PISTON HEAD SHAPE:
- DOMED
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 96.00 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- STYLE:
- JE PISTON
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- DISPLACEMENT:
- 449 CC
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- STANDARD
$309.99 -
JE PISTONS Piston Kit 284855
JE PISTONS
$329.99When you're pushing your engine to its limits in professional competition, your pistons need to handle extreme pressures, elevated temperatures, and sustained high RPMs without compromise. JE...09105901- SKU:
- 09105901
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- JE PISTON
- TYPE:
- FORGED SIDE RELIEF DESIGN
- UNITS:
- KIT
- BORE SIZE METRIC:
- 96.00 MM
- PISTON HEAD SHAPE:
- DOMED
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 12.8:1
- DISPLACEMENT:
- 449 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
$329.99 -
JE PISTONS Piston Kit 284856
JE PISTONS
$329.99When you're running at the edge of performance, your pistons need to be engineered for abuse. JE Pistons' 284856 kit delivers the strength and precision required for professional competition and...09105902- SKU:
- 09105902
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- PISTON HEAD SHAPE:
- DOMED
- STYLE:
- JE PISTON
- TYPE:
- FORGED SIDE RELIEF DESIGN
- UNITS:
- KIT
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 96.00 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- DISPLACEMENT:
- 449 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
$329.99 -
JE PISTONS Piston Kit 291514
JE PISTONS
$329.99When you're pushing your engine to the limit in professional competition, your pistons need to survive extreme pressures and temperatures without compromise. JE Pistons' Pro Series 291514 kit...09105903- SKU:
- 09105903
- Availability:
- Ships Same Business Day
- Weight:
- 1.36 LBS
- BORE SIZE METRIC:
- 96.00 MM
- DISPLACEMENT:
- 449 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON HEAD SHAPE:
- DOMED
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 14.0:1
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- PRO SERIES
- UNITS:
- KIT
$329.99Qty in Cart: 0Quantity:Price:$329.99Subtotal: -
JE PISTONS Piston Kit 291516
JE PISTONS
$309.99When you're pushing your engine to its limits in competition or high-performance driving, your pistons need to handle extreme pressures and temperatures without compromise. JE PISTONS' 291516 kit...09105904- SKU:
- 09105904
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE SIZE METRIC:
- 76.80 MM
- COMPRESSION RATIO IMPERIAL:
- 13.8:1
- PISTON HEAD SHAPE:
- DOMED
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- PRO SERIES
- UNITS:
- KIT
$309.99Qty in Cart: 0Quantity:Price:$309.99Subtotal: -
On Sale
JE PISTONS Piston Kit 306372
JE PISTONS
MSRP: $584.57Now: $374.00Was: $584.57When you're pushing your engine to the absolute limit in professional competition, your pistons need to withstand extreme pressures and temperatures without compromise. JE PISTONS' Pro Series 306372...09105915- SKU:
- 09105915
- Availability:
- Ships Same Business Day
- Weight:
- 2.51 LBS
- COMPRESSION RATIO IMPERIAL:
- 11.0:1
- UNITS:
- KIT
- PISTON HEAD SHAPE:
- DOMED
- DISPLACEMENT:
- 932 CC
- RIDING STYLE:
- UTV
- WALL THICKNESS IMPERIAL:
- 0.160'
- BORE SIZE METRIC:
- 96.00 MM
- PRODUCT NAME:
- PISTON KIT
- WALL THICKNESS:
- 0,160'
MSRP: $584.57Now: $374.00Was: $584.57 -
On Sale
JE PISTONS Piston Kit 306373
JE PISTONS
MSRP: $584.57Now: $374.00Was: $584.57When you're pushing your engine to the absolute limit in competition, your pistons need to handle extreme pressures and temperatures without compromise. JE PISTONS' Pro Series 306373 kit combines...09105916- SKU:
- 09105916
- Availability:
- Ships Same Business Day
- Weight:
- 3.90 LBS
- DISPLACEMENT:
- 932 CC
- WALL THICKNESS IMPERIAL:
- 0.160'
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- BORE SIZE METRIC:
- 96.00 MM
- COMPRESSION RATIO IMPERIAL:
- 11.5:1
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- UTV
- WALL THICKNESS:
- 0,160'
MSRP: $584.57Now: $374.00Was: $584.57 -
JE PISTONS Piston Kit 315160
JE PISTONS
$329.99If you're building a competition engine or pushing your daily driver to its limits, piston selection is non-negotiable. JE PISTONS' 315160 kit delivers the strength and precision demanded by...09105923- SKU:
- 09105923
- Availability:
- Ships Same Business Day
- Weight:
- 1.11 LBS
- RIDING STYLE:
- OFF-ROAD
- WALL THICKNESS IMPERIAL:
- 0.160'
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- BORE SIZE METRIC:
- 96.00 MM
- DISPLACEMENT:
- 449 CC
- PRODUCT NAME:
- PISTON KIT
$329.99Qty in Cart: 0Quantity:Price:$329.99Subtotal: -
JE PISTONS Piston Kit 317198
JE PISTONS
$524.99If you're building a high-performance engine destined for the track or strip, piston quality directly determines your engine's reliability and power ceiling. JE's 317198 kit delivers the precision...09105926- SKU:
- 09105926
- Availability:
- Ships Same Business Day
- Weight:
- 2.60 LBS
- UNITS:
- KIT
- WALL THICKNESS IMPERIAL:
- 0.160'
- PISTON HEAD SHAPE:
- DISHED
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 94.00 MM
- DISPLACEMENT:
- 994 CC
- RIDING STYLE:
- UTV
- COMPRESSION RATIO IMPERIAL:
- 11.5:1
$524.99 -
JE PISTONS Piston Kit 317239
JE PISTONS
$329.99If you're building a competition engine or pushing your vehicle to its limits, piston quality directly impacts reliability, combustion efficiency, and power output. JE Pistons' 317239 kit delivers...09105929- SKU:
- 09105929
- Availability:
- Ships Same Business Day
- Weight:
- 1.36 LBS
- PISTON HEAD SHAPE:
- DOMED
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- DISPLACEMENT:
- 449 CC
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 96.00 MM
- PRODUCT NAME:
- PISTON KIT
- WALL THICKNESS IMPERIAL:
- 0.160'
$329.99Qty in Cart: 0Quantity:Price:$329.99Subtotal: -
JE PISTONS Piston Kit 317240
JE PISTONS
$329.99When you're pushing an engine to its absolute limits in competition, factory pistons simply won't cut it. JE PISTONS' Pro Series 317240 kit delivers the precision engineering and extreme durability...09105930- SKU:
- 09105930
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- PRO SERIES
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 449 CC
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE SIZE METRIC:
- 96.00 MM
- COMPRESSION RATIO IMPERIAL:
- 14.5:1
- PRODUCT NAME:
- PISTON KIT
$329.99 -
JE PISTONS Piston Kit 323556
JE PISTONS
$309.99If you're building or rebuilding an engine for competition or extreme duty, your pistons must withstand massive pressures, temperature swings, and detonation forces that stock units simply cannot...09105931- SKU:
- 09105931
- Availability:
- Ships Same Business Day
- Weight:
- 0.76 LBS
- BORE - OVERSIZE:
- STANDARD
- STYLE:
- PRO SERIES
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- PISTON HEAD SHAPE:
- DOMED
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 77.00 MM
- DISPLACEMENT:
- 250 CC
$309.99Qty in Cart: 0Quantity:Price:$309.99Subtotal: -
JE PISTONS Piston Kit 323557
JE PISTONS
$309.99When you're pushing your engine to its limits in competition, your pistons need to handle extreme pressures and temperatures without compromise. JE Pistons' 323557 kit delivers the precision...09105932- SKU:
- 09105932
- Availability:
- Ships Same Business Day
- Weight:
- 1.36 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 14.0:1
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE:
- STANDARD
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- STYLE:
- PRO SERIES
- BORE SIZE METRIC:
- 77.00 MM
- DISPLACEMENT:
- 250 CC
- PISTON HEAD SHAPE:
- DOMED
- TYPE:
- FORGED SIDE RELIEF DESIGN
$309.99 -
JE PISTONS Piston Kit 323558
JE PISTONS
$309.99When 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 323558 kit delivers...09105933- SKU:
- 09105933
- Availability:
- Ships Same Business Day
- Weight:
- 1.36 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 77.00 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- STYLE:
- PRO SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- 14.5:1
- DISPLACEMENT:
- 250 CC
- PISTON HEAD SHAPE:
- DOMED
- TYPE:
- FORGED SIDE RELIEF DESIGN
$309.99 -
JE PISTONS Piston Kit 324915
JE PISTONS
$329.99When you're pushing your engine to the limit in competition, your pistons need to handle extreme combustion pressures and sustained high RPM operation without compromise. JE PISTONS' Pro Series kit...09105939- SKU:
- 09105939
- Availability:
- Ships Same Business Day
- Weight:
- 1.01 LBS
- DISPLACEMENT:
- 450 CC
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 97.00 MM
- COMPRESSION RATIO IMPERIAL:
- 14.0:1
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- PRO SERIES
$329.99Qty in Cart: 0Quantity:Price:$329.99Subtotal: -
JE PISTONS Piston Kit 325025
JE PISTONS
$329.99When you're pushing your engine to the absolute limit in competition, your pistons need to be engineered for extreme duty—not just adequate. JE Pistons' 325025 kit delivers the strength and precision...09105940- SKU:
- 09105940
- Availability:
- Ships Same Business Day
- Weight:
- 1.16 LBS
- UNITS:
- KIT
- WALL THICKNESS IMPERIAL:
- 0.160'
- DISPLACEMENT:
- 478 CC
- PISTON HEAD SHAPE:
- DISHED
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- ATV
- BORE SIZE METRIC:
- 98.00 MM
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- WALL THICKNESS:
- 0,160'
$329.99Qty in Cart: 0Quantity:Price:$329.99Subtotal:
