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
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VERTEX Piston Kit 24213B
VERTEX
$302.95The VERTEX Piston Kit 24213B delivers the durability and precision you need to maximize engine performance and extend top-end life, whether you're running cast or forged internals. Built with heat-treated aluminum and advanced surface coatings, these...09105144- SKU:
- 09105144
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
$302.95 -
VERTEX Piston Kit 24209A
VERTEX
$302.95Whether you're rebuilding a two-stroke or upgrading your four-stroke engine, piston quality directly impacts reliability, power delivery, and engine longevity. The VERTEX Piston Kit 24209A delivers OEM-matched or performance-enhanced options with...09105149- SKU:
- 09105149
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
$302.95 -
VERTEX Piston Kit 24209B
VERTEX
$302.95Whether you're rebuilding a two-stroke or refreshing a four-stroke engine, piston quality directly impacts durability, ring seal, and power output. The VERTEX Piston Kit 24209B delivers OEM-grade reliability with forged or cast options engineered for...09105150- SKU:
- 09105150
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
$302.95 -
VERTEX Piston Kit - High Compression 24023B
VERTEX
$301.95If you're building a high-compression engine that demands reliability under extreme load, the VERTEX Piston Kit 24023B delivers the precision and durability required for sustained performance. Each piston undergoes rigorous T-5 heat treatment to...09103694- SKU:
- 09103694
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- CYLINDER DIAMETER METRIC:
- 77.00 MM
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 4-STROKE
- PISTON DIAMETER METRIC:
- 76.96 MM
- PRODUCT NAME:
- PISTON KIT
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- FORGED HIGH COMPRESSION
- COMPRESSION RATIO IMPERIAL:
- 14.8:1
- UNITS:
- KIT
$301.95 -
VERTEX Piston Kit 23757B
VERTEX
$289.95Whether you're rebuilding a tired engine or upgrading to a high-compression setup, the VERTEX Piston Kit 23757B delivers the precision engineering and durability required for demanding applications. These pistons are engineered to handle extended service...09103179- SKU:
- 09103179
- Availability:
- Ships Same Business Day
- Weight:
- 0.58 LBS
$289.95 -
VERTEX Piston Kit 23761C
VERTEX
$294.95A quality piston kit is fundamental to engine longevity and reliability, especially under high-demand racing or boosted conditions. The VERTEX Piston Kit 23761C combines precision engineering with battle-tested material science to deliver consistent...09103186- SKU:
- 09103186
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- DISPLACEMENT:
- 300 CC
- ENGINE TYPE:
- 2-STROKE
- STYLE:
- CAST REPLICA
- PISTON DIAMETER METRIC:
- 71.95 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- CYLINDER DIAMETER METRIC:
- 72.00 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
$294.95 -
VERTEX Piston Kit 23249B
VERTEX
$223.95Piston durability directly impacts engine reliability and performance longevity. The VERTEX Piston Kit 23249B combines advanced heat-treatment metallurgy with factory-proven coatings to minimize wear during critical break-in periods and extend service...09102553- SKU:
- 09102553
- Availability:
- Ships Same Business Day
- Weight:
- 0.69 LBS
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 66.34 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- STYLE:
- CAST REPLICA
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$223.95 -
VERTEX Piston Kit 23381A
VERTEX
$315.95The VERTEX Piston Kit 23381A delivers the precision and durability required for high-RPM applications and sustained power delivery. Purpose-built with advanced material treatments, these pistons are engineered to minimize wear during break-in while...09102557- SKU:
- 09102557
- Availability:
- Ships Same Business Day
- Weight:
- 0.92 LBS
$315.95Qty in Cart: 0Quantity:Price:$315.95Subtotal: -
VERTEX Piston Kit 23383B
VERTEX
$208.95Piston durability and break-in performance directly impact engine longevity and power delivery. The VERTEX Piston Kit 23383B combines advanced metallurgy with field-proven surface treatments to reduce friction during initial operation while maintaining...09102558- SKU:
- 09102558
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- CYLINDER DIAMETER METRIC:
- 56.00 MM
- DISPLACEMENT:
- 144 CC
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 55.96 MM
- STYLE:
- CAST REPLICA
$208.95 -
VERTEX Piston Kit 23375A
VERTEX
$254.95Piston selection directly impacts your engine's reliability, power delivery, and longevity. The VERTEX Piston Kit 23375A delivers precision-engineered pistons with advanced metallurgy and coating technology, ensuring consistent performance whether you're...09102421- SKU:
- 09102421
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PISTON DIAMETER METRIC:
- 71.94 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 300 CC
- STYLE:
- CAST REPLICA
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- CYLINDER DIAMETER METRIC:
- 72 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$254.95 -
VERTEX Piston Kit 23375C
VERTEX
$254.95Whether you're rebuilding a high-mileage engine or stepping up to forged internals, the VERTEX Piston Kit 23375C delivers the precision and durability needed for reliable performance across the entire RPM range. The combination of advanced metallurgy,...09102422- SKU:
- 09102422
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- DISPLACEMENT:
- 300 CC
- PISTON DIAMETER METRIC:
- 71.96 MM
- CYLINDER DIAMETER METRIC:
- 72 MM
$254.95 -
VERTEX Piston Kit 22995B
VERTEX
$158.95Whether you're rebuilding a tired engine or upgrading to higher compression, the VERTEX Piston Kit 22995B delivers the durability and performance you need to run hard without compromise. VERTEX's proven heat-treatment process and molybdenum-coated skirts...09102034- SKU:
- 09102034
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- CAST REPLICA
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.00 MM
- DISPLACEMENT:
- 125 CC
- PISTON DIAMETER METRIC:
- 53.93 MM
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
$158.95Qty in Cart: 0Quantity:Price:$158.95Subtotal: -
Wiseco Piston Kit Yamaha XT500 1976-1981 4764M08700
WISECO
$239.95If you're running a classic Yamaha XT500, TT500, or SR500, factory pistons won't cut it if you're serious about reliability and power. The Wiseco 4764M08700 delivers a noticeable bump in combustion efficiency and throttle response—exactly what these...09102923- SKU:
- 09102923
- Availability:
- Ships Same Business Day
- Weight:
- 1.20 LBS
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 87.00 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- DISPLACEMENT:
- 499 CC
- BORE - OVERSIZE:
- STANDARD
- RIDING STYLE:
- STREET
- STROKE LENGTH METRIC:
- 84.00 MM
- COMPRESSION RATIO IMPERIAL:
- 9.0:1
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$239.95 -
Wiseco 88mm 9:1 Piston Kit for Yamaha XT500 1976-1981 4764M08800
WISECO
$239.95If you're running a classic Yamaha single-cylinder and want to unlock better combustion efficiency without sacrificing reliability, the Wiseco 4764M08800 delivers the precision engineering that separates a strong rebuild from a mediocre one. The 9:1...09102924- SKU:
- 09102924
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- BORE SIZE METRIC:
- 88.00 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE - OVERSIZE METRIC:
- +1.00 MM
- RIDING STYLE:
- STREET
- STROKE LENGTH METRIC:
- 84.00 MM
- BORE - OVERSIZE:
- +1,00 MM
- DISPLACEMENT:
- 499 CC
- COMPRESSION RATIO IMPERIAL:
- 9.0:1
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$239.95 -
Wiseco Piston Kit Yamaha SR500 1978-1981 XT500 1976-1981 TT500 1977-1981 4783M09000
WISECO
$269.95A worn or compromised piston directly kills engine efficiency and reliability—the Wiseco 4783M09000 restores both with precision-engineered construction built to handle sustained high-RPM loads. If you're running a TT500, XT500, or SR500 and want...09102927- SKU:
- 09102927
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- STROKE LENGTH METRIC:
- 84.00 MM
- BORE - OVERSIZE METRIC:
- +3.00 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- UNITS:
- EACH
- BORE - OVERSIZE:
- +3,00 MM
- BORE SIZE METRIC:
- 90.00 MM
- COMPRESSION RATIO IMPERIAL:
- 9.0:1
- DISPLACEMENT:
- 499 CC
- RIDING STYLE:
- STREET
$269.95 -
Wiseco Piston Kit Honda CRF450R 2017 4978M09600
WISECO
$232.95If you're running a Honda CRF450R and want to unlock serious power gains without compromising reliability, a quality piston kit is non-negotiable. Wiseco's 4978M09600 delivers the compression ratio and material quality that separates a fast bike from a...09102933- SKU:
- 09102933
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- COMPRESSION RATIO IMPERIAL:
- 12.0:1
- DISPLACEMENT:
- 449 CC
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 96.00 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 62.10 MM
$232.95 -
Wiseco Piston Kit Kawasaki KX450F 2015 40125M09603
WISECO
$239.95The stock piston in your KX450F won't cut it if you're serious about race-day performance. Wiseco's 4980M09600 kit delivers a 12.5:1 compression ratio that translates to measurable gains in power and throttle response, while aerospace-grade aluminum...09102935- SKU:
- 09102935
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- DISPLACEMENT:
- 449 CC
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 96.00 MM
- COMPRESSION RATIO IMPERIAL:
- 12.5:1
- ENGINE TYPE:
- 4-STROKE
- STROKE LENGTH METRIC:
- 62.10 MM
$239.95Qty in Cart: 0Quantity:Price:$239.95Subtotal: -
Wiseco Piston Kit Honda CRF250R 2004-2007 4984M08200
WISECO
$264.95Stock pistons in your CRF250R can't handle sustained performance demands, limiting your engine's potential on the track or trail. Wiseco's 4984M08200 kit delivers measurable gains in throttle response and reliability through precision engineering and a...09102938- SKU:
- 09102938
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- BORE - OVERSIZE METRIC:
- +4.00 MM
- BORE - OVERSIZE:
- +4,00 MM
- BORE SIZE METRIC:
- 82.00 MM
- DISPLACEMENT:
- 276 CC
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 52.20 MM
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$264.95 -
Wiseco Piston Kit Honda XR650L 1993-2017 10.5:1 101mm Bore 4989M10100
WISECO
$248.95If you're running a Honda XR650L that's seen serious miles, piston wear directly impacts throttle response, compression, and overall reliability. The Wiseco 4989M10100 restores—and exceeds—factory performance with a purpose-built design that handles both...09102940- SKU:
- 09102940
- Availability:
- Ships Same Business Day
- Weight:
- 1.55 LBS
- BORE - OVERSIZE:
- +1,00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- STROKE LENGTH METRIC:
- 82.00 MM
- COMPRESSION RATIO IMPERIAL:
- 10.5:1
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE SIZE METRIC:
- 101.00 MM
- DISPLACEMENT:
- 650 CC
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
$248.95 -
Wiseco Yamaha YZ490 1982-1983 Piston Kit 478M08800
WISECO
$234.95The Yamaha YZ490's original piston wasn't built for sustained high-RPM performance or aggressive riding conditions. The Wiseco 478M08800 replaces worn or damaged pistons with precision-engineered internals that restore compression, improve throttle...478M08800- SKU:
- 478M08800
- Availability:
- Ships Same Business Day
- Weight:
- 1.20 LBS
- BORE - OVERSIZE:
- +1,00 MM
- DISPLACEMENT:
- 487 CC
- PISTON DIAMETER METRIC:
- 87.92 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +1.00 MM
- MODEL:
- FORGED SERIES
- SKIRT COATING:
- NON-COATED
- BORE SIZE METRIC:
- 88.00 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH METRIC:
- 82.00 MM
$234.95
