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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- Qty in Cart
- Quantity
- Price
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On Sale
PROX Piston Kit - 77.96 mm - Kawasaki KX250/KX250X 01.4353.A
PROX
MSRP: $188.95Now: $158.00Was: $188.95Piston Kit - 77.96 mm - Kawasaki KX250/KX250X Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106787- SKU:
- 09106787
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
MSRP: $188.95Now: $158.00Was: $188.95 -
On Sale
PROX Piston Kit - 57.94 mm - Husqvarna TE150i | KTM 150EXC TPI 01.6241.A
PROX
MSRP: $139.95Now: $119.00Was: $139.95Piston Kit - 57.94 mm - Husqvarna TE150i | KTM 150EXC TPI Manufactured in Japan and designed to be OEM replacement, Cast from a high-silicon-content aluminum alloy that meets or exceeds OEM specifications, then CNC-machined to extremely close tolerances,...09106792- SKU:
- 09106792
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
MSRP: $139.95Now: $119.00Was: $139.95 -
On Sale
PROX Piston Kit - 87.96 mm - Gas Gas | Husqvarna | KTM 01.6353.A
PROX
MSRP: $209.95Now: $195.00Was: $229.73Piston Kit - 87.96 mm - Gas Gas | Husqvarna | KTM Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106793- SKU:
- 09106793
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
MSRP: $209.95Now: $195.00Was: $229.73 -
On Sale
PROX Piston Kit - 94.95 mm - Gas Gas | Husqvarna | KTM 01.6434.A
PROX
MSRP: $221.95Now: $183.00Was: $221.95Piston Kit - 94.95 mm - Gas Gas | Husqvarna | KTM Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106794- SKU:
- 09106794
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
MSRP: $221.95Now: $183.00Was: $221.95Qty in Cart: 0Quantity:Price:MSRP: $221.95Now: $183.00Was: $221.95Subtotal: -
On Sale
PROX Piston Kit - 94.95 mm - Husqvarna FE450 | KTM 450EXC-F 01.6440.A
PROX
MSRP: $221.95Now: $167.00Was: $221.95Piston Kit - 94.95 mm - Husqvarna FE450 | KTM 450EXC-F Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact...09106795- SKU:
- 09106795
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
MSRP: $221.95Now: $167.00Was: $221.95 -
On Sale
PROX Piston Kit - 94.96 mm - Gas Gas | Husqvarna | KTM 01.6443.A
PROX
MSRP: $214.95Now: $183.00Was: $214.95Piston Kit - 94.96 mm - Gas Gas | Husqvarna | KTM Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106796- SKU:
- 09106796
- Availability:
- Ships Same Business Day
- Weight:
- 0.83 LBS
MSRP: $214.95Now: $183.00Was: $214.95 -
On Sale
PROX Piston Kit - 94.95 mm - Gas Gas | Husqvarna | KTM 01.6513.A
PROX
MSRP: $221.95Now: $183.00Was: $221.95Piston Kit - 94.95 mm - 01.6513.A High-performance piston kit designed for Gas Gas, Husqvarna, and KTM motorcycles. Includes all essential components: piston, rings, wrist pin, circlips, and instruction sheet. Precision machined using...09106797- SKU:
- 09106797
- Availability:
- Ships Same Business Day
- Weight:
- 0.78 LBS
MSRP: $221.95Now: $183.00Was: $221.95 -
On Sale
PROX Piston Kit - 66.34 mm - Beta RR250/Xtrainer 250 01.7313.A
PROX
MSRP: $159.95Now: $136.00Was: $159.95Piston Kit - 66.34 mm - Beta RR250/Xtrainer 250 Manufactured in Japan and designed to be OEM replacement, Cast from a high-silicon-content aluminum alloy that meets or exceeds OEM specifications, then CNC-machined to extremely close tolerances, Kit...09106798- SKU:
- 09106798
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
MSRP: $159.95Now: $136.00Was: $159.95 -
On Sale
PROX Piston Kit - 75.96 mm - Sherco 250SE-F/250SEF-R 01.7314.A
PROX
MSRP: $209.99Now: $178.00Was: $209.99Piston Kit - 75.96 mm - Sherco 250SE-F/250SEF-R Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106799- SKU:
- 09106799
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
MSRP: $209.99Now: $178.00Was: $209.99 -
On Sale
PROX Piston Kit - 83.95 mm - Sherco 300SE-F/300SEF-R 01.7324.A
PROX
MSRP: $221.95Now: $178.00Was: $221.95Piston Kit - 83.95 mm - Sherco 300SE-F/300SEF-R Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106800- SKU:
- 09106800
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
MSRP: $221.95Now: $178.00Was: $221.95 -
On Sale
PROX Piston Kit - 66.34 mm - Sherco 250SE/250SE-R 01.7334.A
PROX
MSRP: $166.95Now: $136.00Was: $166.95Piston Kit - 66.34 mm - 01.7334.A OEM replacement designed specifically for Sherco 250SE/250SE-R models. Manufactured in Japan for superior quality and reliability. Crafted from high-silicon-content aluminum alloy for enhanced durability. ...09106801- SKU:
- 09106801
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
MSRP: $166.95Now: $136.00Was: $166.95 -
On Sale
PROX Piston Kit - 66.34 mm - Sherco 250SE/250SE-R 01.7337.A
PROX
MSRP: $166.95Now: $136.00Was: $166.95Piston Kit - 66.34 mm - Sherco 250SE/250SE-R 01.7337.A Precision-engineered for perfect fit and performance. Manufactured in Japan ensuring high-quality standards. Made from high-silicon-content aluminum alloy for durability. ...09106802- SKU:
- 09106802
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
MSRP: $166.95Now: $136.00Was: $166.95 -
On Sale
PROX Piston Kit - 71.94 mm - Sherco 300SE/300SE-R 01.7346.A
PROX
MSRP: $221.95Now: $170.00Was: $221.95Piston Kit - 71.94 mm - Sherco 300SE/300SE-R Manufactured in Japan and designed to be OEM replacement, Cast from a high-silicon-content aluminum alloy that meets or exceeds OEM specifications, then CNC-machined to extremely close tolerances, Kit includes...09106803- SKU:
- 09106803
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
MSRP: $221.95Now: $170.00Was: $221.95Qty in Cart: 0Quantity:Price:MSRP: $221.95Now: $170.00Was: $221.95Subtotal: -
On Sale
PROX Piston Kit - 87.96 mm - Beta 350RR 01.7351.A
PROX
MSRP: $221.95Now: $178.00Was: $221.95Piston Kit - 87.96 mm - 01.7351.A Precision machined for optimal performance Includes piston, rings, wrist pin, and circlips OEM-quality piston rings made to exact specifications Comprehensive instruction sheet for easy installation ...09106804- SKU:
- 09106804
- Availability:
- Ships Same Business Day
- Weight:
- 0.69 LBS
MSRP: $221.95Now: $178.00Was: $221.95 -
On Sale
PROX Piston Kit - 87.96 mm - Beta 350RR 01.7355.A
PROX
MSRP: $221.95Now: $178.00Was: $221.95Piston Kit - 87.96 mm - 01.7355.A High-performance piston kit designed for Beta 350RR. Includes piston, rings, wrist pin, circlips, and detailed instruction sheet. Precision machined using advanced CNC technology for optimal performance. ...09106805- SKU:
- 09106805
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
MSRP: $221.95Now: $178.00Was: $221.95 -
On Sale
PROX Piston Kit - 87.96 mm - Beta 390RR 01.7365.A
PROX
MSRP: $221.95Now: $183.00Was: $221.95Piston Kit - 87.96 mm - Beta 390RR Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106806- SKU:
- 09106806
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
MSRP: $221.95Now: $183.00Was: $221.95 -
On Sale
PROX Piston Kit - 94.95 mm - Beta 400RR 01.7411.A
PROX
MSRP: $216.95Now: $183.00Was: $216.95Piston Kit - 94.95 mm - Beta 400RR Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106808- SKU:
- 09106808
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
MSRP: $216.95Now: $183.00Was: $216.95 -
On Sale
PROX Piston Kit - 94.95 mm - Beta 450RR 01.7412.A
PROX
MSRP: $221.95Now: $183.00Was: $221.95Piston Kit - 94.95 mm - Beta 450RR Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106809- SKU:
- 09106809
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
MSRP: $221.95Now: $183.00Was: $221.95 -
On Sale
PROX Piston Kit - 94.96 mm - Beta 430RR 01.7415.A
PROX
MSRP: $216.95Now: $183.00Was: $216.95Piston Kit - 94.96 mm - Beta 430RR Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106811- SKU:
- 09106811
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
MSRP: $216.95Now: $183.00Was: $216.95 -
On Sale
PROX Piston Kit - 99.96 mm - Beta 480RR 01.7425.A
PROX
MSRP: $221.95Now: $183.00Was: $221.95Piston Kit - 99.96 mm - Beta 480RR Kit includes piston, rings, wrist pin, circlips and instruction sheet, The piston is precision machined on state of the art CNC equipment, Piston rings are made by OEM factories to exact specifications09106812- SKU:
- 09106812
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
MSRP: $221.95Now: $183.00Was: $221.95