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 - GP1200R - Standard 010-829PK
WSM
$98.28When you're running a GP1200R at the limit, stock pistons become a reliability liability. The WSM Piston Kit delivers OEM-equivalent quality with engineered improvements—specifically the MOS2 coating...010829BP- SKU:
- 010829BP
- Availability:
- Ships Same Business Day
- Weight:
- 1.32 LBS
- BORE SIZE METRIC:
- 80.00 MM
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- MODEL:
- PLATINUM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
$98.28 -
WSM Piston Kit - Polaris 750 - Standard 010-830K
WSM
$89.33When you're pushing a Polaris 750 to its limits, factory pistons can't keep pace with the heat and stress your engine generates. The WSM Piston Kit delivers OEM-equivalent quality with critical...010830- SKU:
- 010830
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 69.75 MM
- MODEL:
- ORIGINAL
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- RIDING STYLE:
- WATERCRAFT
- PISTON MATERIAL:
- ALUMINUM
$89.33 -
WSM Piston Kit - Polaris 750 - +.5 mm 010-830-05K
WSM
$89.33If you're pushing your Polaris 750 to the limit, factory pistons won't cut it—especially at higher boost levels or sustained RPMs. The WSM +.5mm piston kit delivers OEM-matched quality with critical...01083005- SKU:
- 01083005
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- RIDING STYLE:
- WATERCRAFT
- BORE SIZE METRIC:
- 69.75 MM
- MODEL:
- ORIGINAL
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- +0,50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- UNITS:
- KIT
$89.33Qty in Cart: 0Quantity:Price:$89.33Subtotal: -
WSM Piston Kit - Polaris - +.5 mm 010-832-05K
WSM
$98.28High-output piston kits demand precision engineering and thermal management that stock components simply can't deliver. The WSM +.5 mm Piston Kit brings OEM-matching quality with enhanced durability...01083205- SKU:
- 01083205
- Availability:
- Ships Same Business Day
- Weight:
- 0.78 LBS
- RIDING STYLE:
- WATERCRAFT
- BORE SIZE METRIC:
- 81.00 MM
- MODEL:
- ORIGINAL
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- +0,50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- UNITS:
- KIT
$98.28Qty in Cart: 0Quantity:Price:$98.28Subtotal: -
WSM Piston Kit - Yamaha - Standard 010-826K
WSM
$89.33If you're rebuilding a Yamaha engine or replacing worn pistons, the WSM Piston Kit delivers OEM-equivalent quality with performance-focused engineering. The MOS2-coated skirts reduce friction and...010826- SKU:
- 010826
- Availability:
- Ships Same Business Day
- Weight:
- 1.19 LBS
- PISTON MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 84.00 MM
- MODEL:
- ORIGINAL
$89.33Qty in Cart: 0Quantity:Price:$89.33Subtotal: -
WSM Piston Kit - Yamaha - +.25 mm 010-826-04K
WSM
$89.33Stock pistons can't handle the demands of high-performance builds—thermal stress, detonation, and friction all contribute to premature failure and power loss. The WSM Piston Kit delivers OEM-grade...01082604- SKU:
- 01082604
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- BORE - OVERSIZE:
- +0,25 MM
- RIDING STYLE:
- WATERCRAFT
- MODEL:
- ORIGINAL
- PISTON MATERIAL:
- ALUMINUM
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +0.25 MM
- BORE SIZE METRIC:
- 84.00 MM
- PRODUCT NAME:
- PISTON KIT
$89.33Qty in Cart: 0Quantity:Price:$89.33Subtotal: -
WSM Piston Kit - Yamaha - +.5 mm 010-826-05K
WSM
$89.33A properly matched piston kit is critical for reliable high-RPM performance and cylinder longevity. WSM's +.5mm oversized pistons deliver OEM-quality construction with performance-focused...01082605- SKU:
- 01082605
- Availability:
- Ships Same Business Day
- Weight:
- 1.19 LBS
- BORE SIZE METRIC:
- 84.00 MM
- MODEL:
- ORIGINAL
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
- BORE - OVERSIZE:
- +0,50 MM
- BORE - OVERSIZE METRIC:
- +0.50 MM
- UNITS:
- KIT
- PRODUCT NAME:
- PISTON KIT
$89.33Qty in Cart: 0Quantity:Price:$89.33Subtotal: -
WSM Piston Kit - K1200 - Standard 010-841PK
WSM
$98.28Stock pistons wear down, lose compression, and rob your engine of power and efficiency. The WSM Piston Kit K1200 restores your engine to peak performance with OEM-matching quality and engineering...010841P- SKU:
- 010841P
- Availability:
- Ships Same Business Day
- Weight:
- 1.32 LBS
- PRODUCT NAME:
- PISTON KIT
- MODEL:
- PLATINUM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 80.00 MM
$98.28 -
WSM Piston Kit - Kawasaki - Standard 010-812K
WSM
$73.24If you're rebuilding a Kawasaki engine or replacing worn pistons, you need a kit engineered to handle the demands of high-RPM operation without sacrificing longevity. WSM's piston kit delivers...010812X- SKU:
- 010812X
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- BORE SIZE METRIC:
- 75.00 MM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- ORIGINAL
$73.24Qty in Cart: 0Quantity:Price:$73.24Subtotal: -
WSM Piston Kit - Sea-Doo - Standard 010-815K
WSM
$73.24A quality piston kit is the foundation of reliable, high-output engine performance—especially in demanding two-stroke applications where heat and friction directly impact power delivery and component...010815- SKU:
- 010815
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- PISTON MATERIAL:
- ALUMINUM
- BORE - OVERSIZE:
- STANDARD
- BORE SIZE METRIC:
- 76.00 MM
- MODEL:
- ORIGINAL
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE METRIC:
- STANDARD
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- KIT
$73.24Qty in Cart: 0Quantity:Price:$73.24Subtotal: -
WSM Piston Kit - Sea-Doo - +1 mm 010-815-07K
WSM
$73.24When you're pushing your Sea-Doo to the limit, your stock pistons become the weak link in the chain. The WSM Piston Kit delivers OEM-matching quality with engineered upgrades—MOS2 coating on the...01081507- SKU:
- 01081507
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- BORE SIZE METRIC:
- 76.00 MM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- +1,00 MM
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +1.00 MM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
- MODEL:
- ORIGINAL
$73.24Qty in Cart: 0Quantity:Price:$73.24Subtotal: -
MOOSE RACING Piston Kit - 43.46 mm MSE24352B
MOOSE RACING
$127.95A quality piston kit is fundamental to engine reliability and longevity, especially under high-load conditions where thermal stress and wear accelerate component failure. The MOOSE RACING Piston Kit...09105957- SKU:
- 09105957
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
- PISTON DIAMETER METRIC:
- 43.46 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
$127.95Qty in Cart: 0Quantity:Price:$127.95Subtotal: -
MOOSE RACING Piston Kit MSE24384B
MOOSE RACING
$191.95Engine longevity depends on reliable piston performance, especially in high-demand applications where thermal stress and friction accelerate wear. The MOOSE RACING Piston Kit MSE24384B delivers...09106021- SKU:
- 09106021
- Availability:
- Ships Same Business Day
- Weight:
- 0.81 LBS
- UNITS:
- KIT
- PISTON DIAMETER METRIC:
- 66.36 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- OFF-ROAD
$191.95 -
MOOSE RACING Piston Kit MSE24385B
MOOSE RACING
$154.95Factory pistons wear out—especially under high RPM or forced induction conditions. The MOOSE RACING Piston Kit MSE24385B combines gravity-cast aluminum with 18% silicon content to dramatically reduce...09106023- SKU:
- 09106023
- Availability:
- Ships Same Business Day
- Weight:
- 0.61 LBS
- PISTON DIAMETER METRIC:
- 71.96 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
$154.95Qty in Cart: 0Quantity:Price:$154.95Subtotal: -
MOOSE RACING Piston Kit - 66.36 mm MSE22521B
MOOSE RACING
$203.65A piston kit engineered for durability and extended service life, the MOOSE RACING MSE22521B combines gravity-cast aluminum with 18% silicon content to resist wear and thermal distortion under...09102679- SKU:
- 09102679
- Availability:
- Ships Same Business Day
- Weight:
- 0.74 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- CAST REPLICA
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- STOCK
- PISTON DIAMETER METRIC:
- 66.36 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$203.65 -
MOOSE RACING Piston Kit - 53.94 mm MSE22189B
MOOSE RACING
$146.95If you're rebuilding an engine or recovering from ring blow-by, a quality piston kit is non-negotiable. MOOSE Racing's gravity-cast design with 18% silicon content resists wear and thermal...09102669- SKU:
- 09102669
- Availability:
- Ships Same Business Day
- Weight:
- 0.37 LBS
- ENGINE TYPE:
- 2-STROKE
- STYLE:
- CAST REPLICA
- COMPRESSION RATIO IMPERIAL:
- STOCK
- PISTON DIAMETER METRIC:
- 53.94 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- DISPLACEMENT:
- 125 CC
- CYLINDER DIAMETER METRIC:
- 54.00 MM
- PRODUCT NAME:
- PISTON KIT
$146.95 -
MOOSE RACING Piston Kit - 53.94 mm MSE22685C
MOOSE RACING
$99.95A piston kit is one of the most critical internal upgrades for extending engine life and maintaining peak performance under high-load conditions. The MOOSE Racing MSE22685C combines gravity-cast...09102689- SKU:
- 09102689
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- PISTON DIAMETER METRIC:
- 53.94 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
$99.95Qty in Cart: 0Quantity:Price:$99.95Subtotal: -
MOOSE RACING Piston Kit - 44.45 mm MSE22860B
MOOSE RACING
$113.35A piston kit is fundamental to engine longevity and reliability—especially under high-load conditions. The MOOSE RACING MSE22860B combines precision gravity-cast construction with wear-resistant...09102697- SKU:
- 09102697
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON DIAMETER METRIC:
- 44.45 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$113.35 -
JE PISTONS Piston Kit 291517
JE PISTONS
$309.99When you're pushing your engine to the absolute limit in competition or extreme performance applications, piston failure isn't an option. The JE PISTONS Piston Kit 291517 delivers the strength,...09105905- SKU:
- 09105905
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- BORE SIZE METRIC:
- 76.80 MM
- COMPRESSION RATIO IMPERIAL:
- 14.2:1
- BORE - OVERSIZE METRIC:
- STANDARD
- PISTON HEAD SHAPE:
- DOMED
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- FORGED SIDE RELIEF DESIGN
- BORE - OVERSIZE:
- STANDARD
- STYLE:
- PRO SERIES
$309.99Qty in Cart: 0Quantity:Price:$309.99Subtotal: -
JE PISTONS Piston Kit 292330
JE PISTONS
$269.99When you're pushing your engine to the limit in professional competition, your pistons need to survive extreme pressures and temperatures without compromise. JE Pistons' 2618-T6 forged aluminum...09105906- SKU:
- 09105906
- Availability:
- Ships Same Business Day
- Weight:
- 1.51 LBS
- BORE - OVERSIZE:
- +1,00 MM
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- 9.0:1
- PISTON HEAD SHAPE:
- FLAT TOP
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- STYLE:
- JE PISTON
- BORE - OVERSIZE METRIC:
- +1.00 MM
- TYPE:
- ROUND FORGED DESIGN
- UNITS:
- KIT
- BORE SIZE METRIC:
- 101.00 MM
- DISPLACEMENT:
- 650 CC
- RIDING STYLE:
- OFF-ROAD
$269.99Qty in Cart: 0Quantity:Price:$269.99Subtotal:
