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!
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On Sale
Wossner Piston Kit 62.02 mm Beta RR 200 2019-2024 8325DC
WOSSNER
MSRP: $142.00Now: $134.90Was: $142.00Stock pistons accumulate carbon deposits and wear unevenly—especially in high-demand applications like the Beta RR 200. This Wossner kit replaces worn components with aerospace-grade aluminum and a...09106634- SKU:
- 09106634
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
MSRP: $142.00Now: $134.90Was: $142.00 -
On Sale
Wossner Piston Kit 53.95mm Yamaha YZ125 2005-2021 8302DA
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00The stock piston in your YZ125 is subject to constant thermal stress and detonation cycles that accelerate wear—especially if you're pushing higher RPMs or running aggressive jetting. A quality...09106635- SKU:
- 09106635
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
MSRP: $132.00Now: $125.40Was: $132.00 -
On Sale
Wossner Piston Kit 53.96mm Yamaha YZ125 2005-2021 8302DB
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00If you're running a YZ125 and looking to maximize power delivery and engine longevity, a quality piston kit is non-negotiable. Wossner's 53.96mm piston combines precision engineering with proven...09106636- SKU:
- 09106636
- Availability:
- Ships Same Business Day
- Weight:
- 0.46 LBS
MSRP: $132.00Now: $125.40Was: $132.00 -
On Sale
Wossner Piston Kit 53.97mm Yamaha YZ125 2005-2021 8302DC
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00A worn or damaged piston directly compromises engine efficiency, power delivery, and longevity—especially critical for YZ125 two-stroke engines where precision tolerances are unforgiving. The Wossner...09106637- SKU:
- 09106637
- Availability:
- Ships Same Business Day
- Weight:
- 0.46 LBS
MSRP: $132.00Now: $125.40Was: $132.00 -
On Sale
Wossner Piston Kit 53.93mm for Sherco 125 SE-R 2018-2025 8303DA
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00Your Sherco's engine performance depends on a piston that can handle sustained load cycles and elevated combustion pressures without sacrificing reliability. The Wossner 53.93mm piston kit delivers...09106638- SKU:
- 09106638
- Availability:
- Ships Same Business Day
- Weight:
- 0.48 LBS
MSRP: $132.00Now: $125.40Was: $132.00 -
On Sale
Wossner Piston Kit 53.94 mm Sherco 125 SE-R 2018-2025 8303DB
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00When your Sherco 125 SE-R demands peak performance, a worn piston compromises power delivery and increases mechanical noise. This Wossner 53.94 mm piston kit restores efficiency and reliability with...09106639- SKU:
- 09106639
- Availability:
- Ships Same Business Day
- Weight:
- 0.43 LBS
MSRP: $132.00Now: $125.40Was: $132.00 -
On Sale
Wossner Piston Kit 53.95 mm Sherco 125 SE-R 2018-2025 8303DC
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00The stock piston in your 2018-2025 Sherco 125 SE-R experiences wear and friction that directly impact power delivery and engine longevity. This Wossner piston kit replaces that wear with...09106640- SKU:
- 09106640
- Availability:
- Ships Same Business Day
- Weight:
- 0.46 LBS
MSRP: $132.00Now: $125.40Was: $132.00 -
On Sale
Wossner Piston Kit 66.35mm Yamaha YZ250 1999-2025 8217DA
WOSSNER
MSRP: $182.00Now: $172.90Was: $182.00The Wossner 8217DA piston kit delivers the compression ratio stability and durability your YZ250 demands, whether you're pushing hard at the track or rebuilding after a season of aggressive riding...09106641- SKU:
- 09106641
- Availability:
- Ships Same Business Day
- Weight:
- 0.73 LBS
MSRP: $182.00Now: $172.90Was: $182.00 -
On Sale
Wossner Piston Kit 66.36mm Yamaha YZ250 1999-2020 8217DB
WOSSNER
MSRP: $182.00Now: $172.90Was: $182.00If you're running a YZ250 that sees serious track time, piston wear is inevitable—and it directly impacts combustion efficiency, throttle response, and engine longevity. This Wossner kit delivers...09106642- SKU:
- 09106642
- Availability:
- Ships Same Business Day
- Weight:
- 0.68 LBS
MSRP: $182.00Now: $172.90Was: $182.00 -
On Sale
Wossner Piston Kit 89.42mm Honda CR500R 1985-2001 8229D050
WOSSNER
MSRP: $192.00Now: $182.40Was: $192.00Stock pistons limit your Honda CR500R's potential—they can't withstand the demands of aggressive riding or consistent high-RPM operation. The Wossner 89.42mm Piston Kit delivers the strength and...09106643- SKU:
- 09106643
- Availability:
- Ships Same Business Day
- Weight:
- 1.18 LBS
MSRP: $192.00Now: $182.40Was: $192.00 -
On Sale
Wossner Piston Kit 89.92mm Honda CR500R 1985-2001 8229D100
WOSSNER
MSRP: $192.00Now: $182.40Was: $192.00If you're running a Honda CR500R, your piston kit directly determines how much power you can reliably extract from your engine—and whether that power translates to consistent performance across the...09106644- SKU:
- 09106644
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
MSRP: $192.00Now: $182.40Was: $192.00Qty in Cart: 0Quantity:Price:MSRP: $192.00Now: $182.40Was: $192.00Subtotal: -
On Sale
Wossner Piston Kit 88.92mm Honda CR500R 1984-2001 8229DA
WOSSNER
MSRP: $192.00Now: $182.40Was: $192.00If you're running a Honda CR500R and want reliable power delivery without sacrificing durability, a quality piston kit is non-negotiable. This Wossner unit maintains consistent compression and...09106645- SKU:
- 09106645
- Availability:
- Ships Same Business Day
- Weight:
- 1.17 LBS
MSRP: $192.00Now: $182.40Was: $192.00 -
On Sale
Wossner Piston Kit 53.96mm Yamaha YZ125 2022-2025 8321DB
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00A worn or damaged piston directly compromises combustion efficiency, throttle response, and engine longevity—especially critical in a high-revving two-stroke like the YZ125. The Wossner 8321DB...09106610- SKU:
- 09106610
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
MSRP: $132.00Now: $125.40Was: $132.00 -
On Sale
Wossner Piston Kit 53.97mm Yamaha YZ125 2022-2024 8321DC
WOSSNER
MSRP: $132.00Now: $125.40Was: $132.00If you're running a YZ125 at the limit, piston wear becomes your enemy—compromising combustion efficiency, increasing blow-by, and shortening engine life. This Wossner kit replaces worn internals...09106611- SKU:
- 09106611
- Availability:
- Ships Same Business Day
- Weight:
- 0.42 LBS
MSRP: $132.00Now: $125.40Was: $132.00Qty in Cart: 0Quantity:Price:MSRP: $132.00Now: $125.40Was: $132.00Subtotal: -
On Sale
PROX Piston Kit - 78.97 mm - Honda CRF250R/CRF250RX 01.1350.A
PROX
MSRP: $188.95Now: $158.00Was: $188.95A worn or damaged piston compromises engine compression, throttle response, and overall reliability—especially critical in a high-revving 250cc four-stroke. The PROX Piston Kit delivers...09106779- SKU:
- 09106779
- Availability:
- Ships Same Business Day
- Weight:
- 0.53 LBS
MSRP: $188.95Now: $158.00Was: $188.95 -
On Sale
PROX Piston Kit - 53.95 mm - Yamaha YZ125/YZ125X 01.2232.A
PROX
MSRP: $121.95Now: $90.00Was: $121.95A worn or damaged piston directly compromises your YZ125/YZ125X's power delivery, compression, and engine reliability. The PROX 53.95 mm Piston Kit restores your engine to OEM performance...09106780- SKU:
- 09106780
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
MSRP: $121.95Now: $90.00Was: $121.95 -
On Sale
PROX Piston Kit - 96.95 mm - Yamaha WR450F/YZ450F/YZ450FX 01.2448.A
PROX
MSRP: $210.95Now: $167.00Was: $210.95When your Yamaha WR450F or YZ450F demands more from its engine, a quality piston kit is non-negotiable. This PROX kit delivers precision-machined components engineered to exact OEM specifications,...09106781- SKU:
- 09106781
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
MSRP: $210.95Now: $167.00Was: $210.95 -
On Sale
PROX Piston Kit - 96.95 mm - Yamaha WR450F/YZ450F/YZ450FX 01.2450.A
PROX
MSRP: $221.95Now: $183.00Was: $221.95A piston kit is one of the most critical components in your engine's combustion chamber—it directly impacts power delivery, reliability, and longevity. The PROX 96.95 mm kit for your...09106782- SKU:
- 09106782
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
MSRP: $221.95Now: $183.00Was: $221.95 -
On Sale
PROX Piston Kit - 96.95 mm - Yamaha WR450F/YZ450F/YZ450FX 01.2453.A
PROX
MSRP: $221.95Now: $183.00Was: $221.95A worn or damaged piston directly impacts your WR450F or YZ450F's compression ratio, throttle response, and overall reliability—especially under high-RPM racing conditions. This PROX piston kit...09106783- SKU:
- 09106783
- Availability:
- Ships Same Business Day
- Weight:
- 0.93 LBS
MSRP: $221.95Now: $183.00Was: $221.95 -
On Sale
PROX Piston Kit - 77.96 mm - Kawasaki KX250/KX250X 01.4353.A
PROX
MSRP: $188.95Now: $158.00Was: $188.95The piston is the heart of your engine's combustion cycle—wear, scoring, or improper tolerances kill power and reliability. This PROX kit delivers OEM-equivalent precision for the Kawasaki...09106787- SKU:
- 09106787
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
MSRP: $188.95Now: $158.00Was: $188.95
