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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On Sale
VERTEX Piston Kit 22813CD
VERTEX
MSRP: $100.95Now: $90.86Was: $100.95Whether you're rebuilding a worn engine or stepping up to higher compression for more power, the VERTEX Piston Kit 22813CD delivers the durability and precision you need to keep your engine performing at peak output. VERTEX pistons are engineered for...09102064- SKU:
- 09102064
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- DISPLACEMENT:
- 50 CC
- PISTON DIAMETER METRIC:
- 39.47 MM
- CYLINDER DIAMETER METRIC:
- 39.50 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
MSRP: $100.95Now: $90.86Was: $100.95 -
On Sale
VERTEX Piston Kit 23630A
VERTEX
MSRP: $217.95Now: $196.16Was: $217.95The VERTEX Piston Kit 23630A delivers the durability and precision your engine demands, whether you're building a competitive race platform or maximizing longevity in a high-output street engine. Factory heat-treatment and advanced skirt coatings reduce...09102066- SKU:
- 09102066
- Availability:
- Ships Same Business Day
- Weight:
- 0.79 LBS
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 66.34 MM
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
MSRP: $217.95Now: $196.16Was: $217.95 -
On Sale
VERTEX Piston Kit 23630B
VERTEX
MSRP: $213.95Now: $192.56Was: $213.95A piston kit is the heart of your engine's combustion cycle—choosing the right one directly impacts reliability, longevity, and power delivery. The VERTEX Piston Kit 23630B combines advanced metallurgy with proven surface treatments to withstand extreme...09102067- SKU:
- 09102067
- Availability:
- Ships Same Business Day
- Weight:
- 0.79 LBS
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- CYLINDER DIAMETER METRIC:
- 66.40 MM
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- PISTON DIAMETER METRIC:
- 66.35 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
MSRP: $213.95Now: $192.56Was: $213.95 -
On Sale
VERTEX Piston Kit 22978A
VERTEX
MSRP: $302.95Now: $272.66Was: $302.95The VERTEX Piston Kit 22978A delivers the precision engineering and durability required for serious engine builds. Whether you're running a high-compression setup or increasing displacement, these pistons are engineered to handle sustained high-RPM loads...09102070- SKU:
- 09102070
- Availability:
- Ships Same Business Day
- Weight:
- 0.84 LBS
MSRP: $302.95Now: $272.66Was: $302.95 -
On Sale
VERTEX Piston Kit - Stroker 23879B
VERTEX
MSRP: $176.95Now: $159.26Was: $176.95Whether you're building a high-displacement stroker engine or pushing the limits of your current platform, the VERTEX Piston Kit 23879B delivers the precision engineering and material science your engine demands. These pistons are purpose-built to handle...09103678- SKU:
- 09103678
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- CAST STROKER
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 52.00 MM
- PISTON DIAMETER METRIC:
- 51.96 MM
- RIDING STYLE:
- OFF-ROAD
- DISPLACEMENT:
- 112 CC
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
MSRP: $176.95Now: $159.26Was: $176.95 -
On Sale
VERTEX Piston Kit 24018A
VERTEX
MSRP: $262.95Now: $236.66Was: $262.95Premium pistons are the foundation of reliable high-RPM performance, and the VERTEX 24018A kit delivers the durability you need for sustained power without failure. Factory OEM pistons often compromise between cost and longevity—this kit eliminates that...09103679- SKU:
- 09103679
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
MSRP: $262.95Now: $236.66Was: $262.95 -
On Sale
VERTEX Piston Kit - High Compression 24021B
VERTEX
MSRP: $289.95Now: $260.96Was: $289.95High-compression pistons are essential for maximizing power output in forced induction and naturally aspirated engines that demand peak performance. The VERTEX 24021B kit delivers precision engineering with proprietary heat-treating and skirt coating...09103688- SKU:
- 09103688
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- PISTON DIAMETER METRIC:
- 76.96 MM
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- FORGED HIGH COMPRESSION
- COMPRESSION RATIO IMPERIAL:
- 14.3:1
- ENGINE TYPE:
- 4-STROKE
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- CYLINDER DIAMETER METRIC:
- 77.00 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- DISPLACEMENT:
- 250 CC
- PRODUCT NAME:
- PISTON KIT
MSRP: $289.95Now: $260.96Was: $289.95 -
On Sale
VERTEX Piston Kit - High Compression 24022B
VERTEX
MSRP: $301.95Now: $298.76Was: $301.95If you're building an engine that demands reliability under extreme combustion pressures, the VERTEX Piston Kit 24022B delivers the precision tolerances and durability required for sustained high-RPM performance. The T-5 heat treatment and molybdenum...09103691- SKU:
- 09103691
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- PRODUCT NAME:
- PISTON KIT
- CYLINDER DIAMETER METRIC:
- 96.00 MM
- DISPLACEMENT:
- 450 CC
- PISTON DIAMETER METRIC:
- 95.97 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- ENGINE TYPE:
- 4-STROKE
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- FORGED HIGH COMPRESSION
MSRP: $301.95Now: $298.76Was: $301.95 -
On Sale
VERTEX Piston Kit VTKTC22915B
VERTEX
MSRP: $354.95Now: $319.46Was: $354.95Whether you're building a high-revving engine or pushing existing power limits, piston quality directly impacts reliability and longevity under extreme conditions. The VERTEX Piston Kit VTKTC22915B delivers engineered durability through advanced...09103717- SKU:
- 09103717
- Availability:
- Ships Same Business Day
- Weight:
- 2.25 LBS
MSRP: $354.95Now: $319.46Was: $354.95 -
On Sale
VERTEX Piston Kit VTKTC22915B-1
VERTEX
MSRP: $354.95Now: $319.46Was: $354.95Stock pistons struggle under high-boost or extended track sessions—they warp, wear prematurely, and compromise your engine's reliability. The VERTEX Piston Kit VTKTC22915B-1 solves this with advanced heat treatment and low-friction coatings that extend...09103718- SKU:
- 09103718
- Availability:
- Ships Same Business Day
- Weight:
- 2.45 LBS
MSRP: $354.95Now: $319.46Was: $354.95 -
On Sale
VERTEX Piston Kit VTKTC22951A
VERTEX
MSRP: $327.95Now: $295.16Was: $327.95A piston kit is the heart of engine performance—it directly impacts compression ratio, combustion efficiency, and overall durability under extreme operating conditions. The VERTEX Piston Kit VTKTC22951A delivers precision-engineered pistons built to...09103721- SKU:
- 09103721
- Availability:
- Ships Same Business Day
- Weight:
- 2.55 LBS
MSRP: $327.95Now: $295.16Was: $327.95 -
On Sale
VERTEX Piston Kit VTKTC22983A
VERTEX
MSRP: $302.95Now: $272.66Was: $302.95A quality piston kit is the foundation of reliable high-RPM performance, and the VERTEX Piston Kit VTKTC22983A delivers the durability and precision demanded by serious builders. The T-5 heat treatment cycle ensures superior hardness and resistance to...09103724- SKU:
- 09103724
- Availability:
- Ships Same Business Day
- Weight:
- 2.05 LBS
MSRP: $302.95Now: $272.66Was: $302.95 -
Wiseco Piston Kit 86mm Bore Yamaha DT400 1975-1978 MX400 1975 232M08600
WISECO
$232.95The Wiseco Piston Kit delivers the reliability and performance precision you need for a complete top-end rebuild on your classic Yamaha DT400 or MX400. This +1.00mm oversized piston compensates for wear and restores compression, giving you crisp throttle...232M08600- SKU:
- 232M08600
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON DIAMETER METRIC:
- 85.92 MM
- PRODUCT NAME:
- PISTON KIT
- STROKE LENGTH METRIC:
- 70.00 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- DISPLACEMENT:
- 397 CC
- MODEL:
- FORGED SERIES
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- SKIRT COATING:
- NON-COATED
- UNITS:
- KIT
- BORE - OVERSIZE:
- +1,00 MM
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 86.00 MM
$232.95 -
Wiseco Piston Kit Honda TRX400EX 1999-2008 4606M08700
WISECO
$219.95If you're running a Honda TRX400EX, cylinder wear and stock piston limitations will eventually throttle your engine's potential. The Wiseco Piston Kit 4606M08700 restores combustion efficiency and adds measurable power while maintaining the reliability...09102910- SKU:
- 09102910
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- BORE - OVERSIZE METRIC:
- +2.00 MM
- STROKE LENGTH METRIC:
- 70.00 MM
- BORE SIZE METRIC:
- 87.00 MM
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- DISPLACEMENT:
- 397 CC
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- +2,00 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
$219.95Qty in Cart: 0Quantity:Price:$219.95Subtotal: -
Wiseco Piston Kit 88mm 11:1 Compression for Honda XR400R 1996-2004 4628M08800
WISECO
$244.95Factory pistons wear out—especially in high-demand riding conditions. This Wiseco piston kit restores lost compression and power while delivering the durability needed for both trail abuse and competition. At 88mm with an 11:1 compression ratio, you're...09102915- SKU:
- 09102915
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- BORE - OVERSIZE:
- +3,00 MM
- COMPRESSION RATIO IMPERIAL:
- 11.0:1
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- STROKE LENGTH METRIC:
- 70.00 MM
- BORE SIZE METRIC:
- 88.00 MM
- DISPLACEMENT:
- 397 CC
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE METRIC:
- +3.00 MM
$244.95Qty in Cart: 0Quantity:Price:$244.95Subtotal: -
Wiseco Piston Kit Yamaha XT350 1985-2000 86mm 9:1 Compression 4674M08600
WISECO
$199.95If you're running a Yamaha XT350 or TT350, a worn or damaged piston directly impacts combustion efficiency, throttle response, and overall reliability. The Wiseco 4674M08600 replaces your factory piston with a precision-engineered component that restores...09102916- SKU:
- 09102916
- Availability:
- Ships Same Business Day
- Weight:
- 0.97 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- DISPLACEMENT:
- 346 CC
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 59.60 MM
- BORE SIZE METRIC:
- 86.00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- COMPRESSION RATIO IMPERIAL:
- 9.0:1
$199.95 -
Wiseco Piston Kit Yamaha XT350 1985-2000 87.50mm 9:1 4674M08750
WISECO
$184.95When your XT350 starts showing signs of wear—loss of compression, reduced throttle response, or visible piston scoring—a quality piston kit is essential to restore engine integrity and performance. The Wiseco 4674M08750 is engineered specifically for...09102917- SKU:
- 09102917
- Availability:
- Ships Same Business Day
- Weight:
- 1.01 LBS
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- UNITS:
- EACH
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 87.00 MM
- DISPLACEMENT:
- 346 CC
- STROKE LENGTH METRIC:
- 59.60 MM
- BORE - OVERSIZE METRIC:
- +1.00 MM
- COMPRESSION RATIO IMPERIAL:
- 9.0:1
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$184.95 -
Wiseco Piston Kit 88.00mm Oversize Yamaha YZ490 1984-1990 546M08800
WISECO
$243.95If you're running a YZ490 and want to unlock real gains in compression ratio and top-end power, a quality oversize piston is non-negotiable. The Wiseco +1.00mm kit gives you the forged strength to handle aggressive tuning and racing demands while...546M08800- SKU:
- 546M08800
- Availability:
- Ships Same Business Day
- Weight:
- 1.40 LBS
- BORE - OVERSIZE METRIC:
- +1.00 MM
- RIDING STYLE:
- OFF-ROAD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
- DISPLACEMENT:
- 487 CC
- STROKE LENGTH:
- 82,00 MM
- BORE - OVERSIZE:
- +1,00 MM
- BORE SIZE METRIC:
- 88.00 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 82.00 MM
$243.95 -
Wiseco Piston 88.5mm Oversize Yamaha WR500Z 1992-1993 546M08850
WISECO
$244.95If you're pushing your Yamaha WR500Z or YZ490 to its limits, stock pistons won't cut it. The Wiseco +1.50mm oversize piston delivers the durability and power you need for serious trail and racing applications, with forged construction that handles...546M08850- SKU:
- 546M08850
- Availability:
- Ships Same Business Day
- Weight:
- 1.25 LBS
- BORE - OVERSIZE METRIC:
- +1.50 MM
- PISTON MATERIAL:
- FORGED
- STROKE LENGTH METRIC:
- 82.00 MM
- BORE SIZE METRIC:
- 88.50 MM
- DISPLACEMENT:
- 487 CC
- STROKE LENGTH:
- 82,00 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- BORE - OVERSIZE:
- +1,50 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$244.95 -
Wiseco Piston 89mm +2mm Oversize for Yamaha YZ490 1984-1990 546M08900
WISECO
$244.95If you're running a Yamaha YZ490 or WR500 at the edge of its limits, factory pistons won't cut it. This Wiseco forged piston is built to withstand the punishment of competitive racing and aggressive trail riding while delivering measurable gains in...546M08900- SKU:
- 546M08900
- Availability:
- Ships Same Business Day
- Weight:
- 1.25 LBS
- BORE - OVERSIZE METRIC:
- +2.00 MM
- DISPLACEMENT:
- 487 CC
- PISTON MATERIAL:
- ALUMINUM ALLOY
- STROKE LENGTH:
- 82,00 MM
- UNITS:
- EACH
- BORE - OVERSIZE:
- +2,00 MM
- PISTON MATERIAL:
- FORGED
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 89.00 MM
- STROKE LENGTH METRIC:
- 82.00 MM
$244.95Qty in Cart: 0Quantity:Price:$244.95Subtotal:
