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Dirt Bike Piston and Ring Kits

Dirt Bike Piston and Ring Kits

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

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
  • VERTEX Piston Kit 23599B

    VERTEX Piston Kit 23599B

    VERTEX

    $271.95
    Whether you're rebuilding a tired engine or upgrading to high-compression performance, the VERTEX Piston Kit 23599B delivers the durability and precision required for sustained high-RPM operation. These forged pistons withstand extreme combustion...
    09102566
    SKU:
    09102566
    Availability:
    Ships Same Business Day
    Weight:
    0.54 LBS
    COMPRESSION RATIO IMPERIAL:
    13.6:1
    PISTON MATERIAL:
    FORGED 2618 ALUMINUM
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    STYLE:
    FORGED REPLICA
    CYLINDER DIAMETER METRIC:
    79.00 MM
    DISPLACEMENT:
    250 CC
    ENGINE TYPE:
    2-STROKE
    PRODUCT NAME:
    PISTON KIT
    PISTON DIAMETER METRIC:
    78.96 MM
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $271.95
    Qty in Cart: 0
    Quantity:
    Price:
    $271.95
    Subtotal:
  • VERTEX Piston Kit 23457B

    VERTEX Piston Kit 23457B

    VERTEX

    $260.95
    A worn or damaged top end forces you to choose between a full rebuild and compromised performance—neither acceptable for serious racers and dedicated enthusiasts. The VERTEX Piston Kit 23457B eliminates that dilemma by delivering OEM-quality replacement...
    09102564
    SKU:
    09102564
    Availability:
    Ships Same Business Day
    Weight:
    0.79 LBS
    PISTON MATERIAL:
    CAST
    PRODUCT NAME:
    PISTON KIT
    UNITS:
    KIT
    RIDING STYLE:
    STREET
    COMPRESSION RATIO IMPERIAL:
    STANDARD
    CYLINDER DIAMETER METRIC:
    72.00 MM
    PISTON DIAMETER METRIC:
    71.95 MM
    STYLE:
    CAST REPLICA
    DISPLACEMENT:
    300 CC
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    ALUMINUM ALLOY
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    $260.95
    Qty in Cart: 0
    Quantity:
    Price:
    $260.95
    Subtotal:
  • On Sale
    ATHENA Piston Kit S4F100000190 ATHENA Piston Kit S4F100000190

    ATHENA Piston Kit S4F100000190

    ATHENA

    MSRP: $257.95
    Now: $232.00
    Was: $257.95
    Engine reliability depends on quality internal components, and pistons are the foundation of any high-performance rebuild or refresh. The ATHENA Piston Kit S4F100000190 delivers precision-engineered pistons with matching rings and clips to restore or...
    09102535
    SKU:
    09102535
    Availability:
    Ships Same Business Day
    Weight:
    0.93 LBS
    RIDING STYLE:
    OFF-ROAD
    STYLE:
    BIG BORE
    PISTON SIZE METRIC:
    STANDARD
    PRODUCT NAME:
    PISTON KIT
    COMPRESSION RATIO IMPERIAL:
    12.0:1
    ENGINE TYPE:
    4-STROKE
    PISTON DIAMETER METRIC:
    100.00 MM
    UNITS:
    EACH
    MSRP: $257.95
    Now: $232.00
    Was: $257.95
    Qty in Cart: 0
    Quantity:
    Price:
    MSRP: $257.95
    Now: $232.00
    Was: $257.95
    Subtotal:
  • On Sale
    ATHENA Piston Kit S4F04700001A

    ATHENA Piston Kit S4F04700001A

    ATHENA

    MSRP: $142.95
    Now: $129.00
    Was: $142.95
    When you're pushing peak RPMs, piston reliability determines whether you finish the race or get sidelined. The ATHENA Piston Kit S4F04700001A delivers the same precision-forged construction and exotic materials trusted by Formula 1 engines, engineered to...
    09102533
    SKU:
    09102533
    Availability:
    Ships Same Business Day
    Weight:
    0.30 LBS
    COMPRESSION RATIO IMPERIAL:
    STOCK
    PRODUCT NAME:
    PISTON KIT
    UNITS:
    KIT
    DISPLACEMENT:
    85 CC
    PISTON HEAD SHAPE:
    DOMED
    RIDING STYLE:
    OFF-ROAD
    BORE SIZE METRIC:
    46.96 MM
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    4032 ALUMINUM ALLOY
    TYPE:
    A
    MSRP: $142.95
    Now: $129.00
    Was: $142.95
    Qty in Cart: 0
    Quantity:
    Price:
    MSRP: $142.95
    Now: $129.00
    Was: $142.95
    Subtotal:
  • On Sale
    ATHENA Piston Kit S4F04500001B

    ATHENA Piston Kit S4F04500001B

    ATHENA

    MSRP: $141.95
    Now: $135.00
    Was: $141.95
    Maximum engine longevity and reliability demand pistons engineered to withstand extreme combustion pressures and thermal cycling. The ATHENA Piston Kit S4F04500001B delivers the precision and durability required for competitive racing and...
    09102532
    SKU:
    09102532
    Availability:
    Ships Same Business Day
    Weight:
    0.30 LBS
    COMPRESSION RATIO IMPERIAL:
    STOCK
    PRODUCT NAME:
    PISTON KIT
    TYPE:
    B
    BORE SIZE METRIC:
    44.97 MM
    PISTON HEAD SHAPE:
    DOMED
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    DISPLACEMENT:
    65 CC
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    4032 ALUMINUM ALLOY
    MSRP: $141.95
    Now: $135.00
    Was: $141.95
    Qty in Cart: 0
    Quantity:
    Price:
    MSRP: $141.95
    Now: $135.00
    Was: $141.95
    Subtotal:
  • On Sale
    ATHENA Piston Kit S4F04500001A

    ATHENA Piston Kit S4F04500001A

    ATHENA

    MSRP: $142.95
    Now: $129.00
    Was: $142.95
    Maximum piston longevity and reliability demand materials engineered for extreme thermal stress—and the ATHENA S4F04500001A delivers exactly that. Whether you're running a two-stroke or four-stroke, this kit uses the same aerospace-grade aluminum alloys...
    09102531
    SKU:
    09102531
    Availability:
    Ships Same Business Day
    Weight:
    0.30 LBS
    COMPRESSION RATIO IMPERIAL:
    STOCK
    PRODUCT NAME:
    PISTON KIT
    BORE SIZE METRIC:
    44.96 MM
    PISTON HEAD SHAPE:
    DOMED
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    DISPLACEMENT:
    65 CC
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    4032 ALUMINUM ALLOY
    TYPE:
    A
    MSRP: $142.95
    Now: $129.00
    Was: $142.95
    Qty in Cart: 0
    Quantity:
    Price:
    MSRP: $142.95
    Now: $129.00
    Was: $142.95
    Subtotal:
  • VERTEX Piston Kit 23378B

    VERTEX Piston Kit 23378B

    VERTEX

    $271.95
    Whether you're rebuilding a tired engine or upgrading to higher compression, the VERTEX Piston Kit 23378B delivers the durability and precision needed for sustained high-RPM performance. The combination of advanced heat treatment, molybdenum-coated...
    09102099
    SKU:
    09102099
    Availability:
    Ships Same Business Day
    Weight:
    1.07 LBS
    DISPLACEMENT:
    450 CC
    PRODUCT NAME:
    PISTON KIT
    STYLE:
    FORGED HIGH COMPRESSION
    UNITS:
    KIT
    PISTON DIAMETER METRIC:
    95.97 MM
    COMPRESSION RATIO IMPERIAL:
    12.9:1
    CYLINDER DIAMETER METRIC:
    96.00 MM
    ENGINE TYPE:
    4-STROKE
    PISTON MATERIAL:
    FORGED 2618 ALUMINUM
    RIDING STYLE:
    OFF-ROAD
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    $271.95
    Qty in Cart: 0
    Quantity:
    Price:
    $271.95
    Subtotal:
  • VERTEX Piston Kit 23198B

    VERTEX Piston Kit 23198B

    VERTEX

    $289.95
    The VERTEX Piston Kit 23198B delivers the durability and precision needed for high-rpm engine demands, whether you're rebuilding after wear or upgrading for peak performance. Built with heat-treated aluminum and a molybdenum disulfide coating, these...
    09102091
    SKU:
    09102091
    Availability:
    Ships Same Business Day
    Weight:
    0.90 LBS
    $289.95
    Qty in Cart: 0
    Quantity:
    Price:
    $289.95
    Subtotal:
  • VERTEX Piston Kit - Standard 22521B

    VERTEX Piston Kit - Standard 22521B

    VERTEX

    $235.95
    A quality piston kit is the foundation of any reliable engine build—especially when you're pushing performance limits. The VERTEX Piston Kit 22521B delivers the durability and precision you need for consistent power delivery across extended racing...
    09101059
    SKU:
    09101059
    Availability:
    Ships Same Business Day
    Weight:
    0.72 LBS
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    ALUMINUM ALLOY
    RIDING STYLE:
    OFF-ROAD
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    STYLE:
    CAST REPLICA
    COMPRESSION RATIO IMPERIAL:
    STANDARD
    PISTON DIAMETER METRIC:
    66.36 MM
    PISTON MATERIAL:
    CAST
    PRODUCT NAME:
    PISTON KIT
    UNITS:
    KIT
    CYLINDER DIAMETER METRIC:
    66.40 MM
    DISPLACEMENT:
    250 CC
    Qty in Cart: 0
    Quantity:
    Price:
    $235.95
    Subtotal:
  • VERTEX Piston Kit - Standard 22712B

    VERTEX Piston Kit - Standard 22712B

    VERTEX

    $158.95
    The VERTEX Piston Kit 22712B delivers the durability and precision your engine demands, whether you're building a street machine or prepping for the track. Heat-treated to withstand extreme combustion pressures and temperatures, these pistons feature a...
    09101056
    SKU:
    09101056
    Availability:
    Ships Same Business Day
    Weight:
    0.36 LBS
    COMPRESSION RATIO IMPERIAL:
    STANDARD
    PISTON MATERIAL:
    CAST
    PRODUCT NAME:
    PISTON KIT
    UNITS:
    KIT
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    ALUMINUM ALLOY
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    CYLINDER DIAMETER METRIC:
    54.00 MM
    PISTON DIAMETER METRIC:
    53.96 MM
    RIDING STYLE:
    OFF-ROAD
    STYLE:
    CAST REPLICA
    DISPLACEMENT:
    125 CC
    $158.95
    Qty in Cart: 0
    Quantity:
    Price:
    $158.95
    Subtotal:
  • VERTEX Piston Kit - Standard 22498B

    VERTEX Piston Kit - Standard 22498B

    VERTEX

    $176.95
    Quality pistons are the foundation of reliable engine performance, especially if you're pushing your build to higher RPMs or boost levels. The VERTEX Piston Kit 22498B delivers the durability and precision you need for consistent power delivery without...
    09101055
    SKU:
    09101055
    Availability:
    Ships Same Business Day
    Weight:
    0.40 LBS
    COMPRESSION RATIO IMPERIAL:
    STANDARD
    PISTON MATERIAL:
    CAST
    PRODUCT NAME:
    PISTON KIT
    CYLINDER DIAMETER METRIC:
    54.00 MM
    PISTON DIAMETER METRIC:
    53.96 MM
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    DISPLACEMENT:
    125 CC
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    ALUMINUM ALLOY
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    STYLE:
    CAST RACE
    Qty in Cart: 0
    Quantity:
    Price:
    $176.95
    Subtotal:
  • VERTEX Piston Kit - Standard 22248B

    VERTEX Piston Kit - Standard 22248B

    VERTEX

    $141.95
    A quality piston kit is the foundation of reliable engine performance, especially under high RPM and boost conditions. The VERTEX Piston Kit 22248B combines precision engineering with proven durability features that reduce wear during critical break-in...
    09101053
    SKU:
    09101053
    Availability:
    Ships Same Business Day
    Weight:
    0.38 LBS
    CYLINDER DIAMETER METRIC:
    54.00 MM
    PISTON DIAMETER METRIC:
    53.96 MM
    PRODUCT NAME:
    PISTON KIT
    COMPRESSION RATIO IMPERIAL:
    STANDARD
    PISTON MATERIAL:
    CAST
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    DISPLACEMENT:
    125 CC
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    ALUMINUM ALLOY
    STYLE:
    CAST REPLICA
    Qty in Cart: 0
    Quantity:
    Price:
    $141.95
    Subtotal:
  • VERTEX Piston Kit - Standard 22499B

    VERTEX Piston Kit - Standard 22499B

    VERTEX

    $118.95
    A quality piston kit is the foundation of reliable engine performance, and the VERTEX Standard 22499B delivers the durability and precision required for both street and track applications. The advanced T-5 heat treatment and molybdenum disulfide coating...
    09101023
    SKU:
    09101023
    Availability:
    Ships Same Business Day
    Weight:
    0.28 LBS
    COMPRESSION RATIO IMPERIAL:
    STANDARD
    PISTON DIAMETER METRIC:
    46.95 MM
    PISTON MATERIAL:
    CAST
    PRODUCT NAME:
    PISTON KIT
    CYLINDER DIAMETER METRIC:
    47.00 MM
    DISPLACEMENT:
    80 CC
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    ENGINE TYPE:
    2-STROKE
    PISTON MATERIAL:
    ALUMINUM ALLOY
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    STYLE:
    CAST REPLICA
    $118.95
    Qty in Cart: 0
    Quantity:
    Price:
    $118.95
    Subtotal:
  • VERTEX Piston Kit 23381B

    VERTEX Piston Kit 23381B

    VERTEX

    $327.95
    The VERTEX Piston Kit 23381B delivers the durability and precision required for sustained high-RPM performance and reliability across demanding racing and modified engine applications. With factory-grade heat treatment and a specialized piston skirt...
    09101020
    SKU:
    09101020
    Availability:
    Ships Same Business Day
    Weight:
    0.92 LBS
    Qty in Cart: 0
    Quantity:
    Price:
    $327.95
    Subtotal:
  • VERTEX Piston Kit 22942B

    VERTEX Piston Kit 22942B

    VERTEX

    $327.95
    If you're building a high-revving engine or pushing your existing platform to the next level, piston quality directly impacts reliability and longevity under sustained load. The VERTEX Piston Kit 22942B delivers OEM-grade durability with purpose-built...
    09101017
    SKU:
    09101017
    Availability:
    Ships Same Business Day
    Weight:
    0.92 LBS
    $327.95
    Qty in Cart: 0
    Quantity:
    Price:
    $327.95
    Subtotal:
  • VERTEX Piston Kit 23379B

    VERTEX Piston Kit 23379B

    VERTEX

    $302.95
    High-revving engines demand pistons engineered for sustained performance under extreme conditions. The VERTEX Piston Kit 23379B combines advanced metallurgy with precision surface coatings to deliver reliable power delivery and extended component life...
    09101012
    SKU:
    09101012
    Availability:
    Ships Same Business Day
    Weight:
    0.90 LBS
    $302.95
    Qty in Cart: 0
    Quantity:
    Price:
    $302.95
    Subtotal:
  • VERTEX Piston Kit 23235A

    VERTEX Piston Kit 23235A

    VERTEX

    $302.95
    A quality piston kit is foundational to engine reliability and performance—especially if you're running higher boost levels or extended track sessions. The VERTEX Piston Kit 23235A delivers the durability and precision fit that serious racers and...
    09101004
    SKU:
    09101004
    Availability:
    Ships Same Business Day
    Weight:
    0.58 LBS
    $302.95
    Qty in Cart: 0
    Quantity:
    Price:
    $302.95
    Subtotal:
  • VERTEX Piston Kit 22925B

    VERTEX Piston Kit 22925B

    VERTEX

    $242.95
    Piston failure is one of the most costly engine catastrophes—and the VERTEX Piston Kit 22925B eliminates the guesswork with OEM-quality construction and race-proven durability. The combination of precision heat treatment and low-friction coating means...
    09100992
    SKU:
    09100992
    Availability:
    Ships Same Business Day
    Weight:
    0.61 LBS
    CYLINDER DIAMETER METRIC:
    64.00 MM
    DISPLACEMENT:
    200 CC
    PRODUCT NAME:
    PISTON KIT
    ENGINE TYPE:
    2-STROKE
    PISTON DIAMETER METRIC:
    63.95 MM
    PISTON MATERIAL:
    CAST
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    COMPRESSION RATIO IMPERIAL:
    STANDARD
    PISTON MATERIAL:
    ALUMINUM ALLOY
    SKIRT COATING:
    MOLYBDENUM DISULPHITE
    STYLE:
    CAST REPLICA
    $242.95
    Qty in Cart: 0
    Quantity:
    Price:
    $242.95
    Subtotal:
  • On Sale
    ATHENA Piston Kit S5F08300005B

    ATHENA Piston Kit S5F08300005B

    ATHENA

    MSRP: $256.95
    Now: $231.00
    Was: $256.95
    Whether you're rebuilding a high-revving two-stroke or fortifying a four-stroke engine, piston quality directly impacts power delivery, longevity, and reliability under extreme conditions. The ATHENA Piston Kit S5F08300005B delivers the precision and...
    09100884
    SKU:
    09100884
    Availability:
    Ships Same Business Day
    Weight:
    0.61 LBS
    PISTON MATERIAL:
    FORGED 2618 ALUMINUM
    DISPLACEMENT:
    250 CC
    ENGINE TYPE:
    4-STROKE
    PRODUCT NAME:
    PISTON KIT
    TYPE:
    B
    BORE SIZE METRIC:
    82.96 MM
    COMPRESSION RATIO IMPERIAL:
    STOCK
    PISTON HEAD SHAPE:
    DOMED
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MSRP: $256.95
    Now: $231.00
    Was: $256.95
    Qty in Cart: 0
    Quantity:
    Price:
    MSRP: $256.95
    Now: $231.00
    Was: $256.95
    Subtotal:
  • On Sale
    ATHENA Piston Kit S4C05800002B

    ATHENA Piston Kit S4C05800002B

    ATHENA

    MSRP: $242.95
    Now: $219.00
    Was: $242.95
    A high-performance piston kit is essential for engines pushing beyond stock limits—whether you're building a race engine or restoring a worn block. The ATHENA S4C05800002B delivers OEM-equivalent quality with precision-engineered components that ensure...
    09100878
    SKU:
    09100878
    Availability:
    Ships Same Business Day
    Weight:
    0.43 LBS
    COMPRESSION RATIO IMPERIAL:
    14.0:1
    ENGINE TYPE:
    2-STROKE
    PISTON DIAMETER METRIC:
    57.95 MM
    PISTON SIZE METRIC:
    STANDARD SIZE B
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    STYLE:
    BIG BORE
    PRODUCT NAME:
    PISTON
    MSRP: $242.95
    Now: $219.00
    Was: $242.95
    Qty in Cart: 0
    Quantity:
    Price:
    MSRP: $242.95
    Now: $219.00
    Was: $242.95
    Subtotal:
  • Total: items /

Adding your products to cart

Big Power, Nice Sound!

Picked up a Pro Circuit pipe and silencer for my YZ125 it’s a game changer. The power feels way better and the sound is awesome.

Tyler D. - 06/12

Perfect Fit

First time ordering here and dang y’all knocked it outta the park! The wheels fit my Ranger UTV perfect, and I’ll definitely be back for more 5 stars all day!

Sarah L. - 08/24

Fast Shipping!!

Ordered on a Monday, and it was on my doorstep by Wednesday! Super impressed with how fast the shipping was.

Jason P. - 09/13

Helps keep cool, works great!

Bought the dual pass Allstar radiator for my build, and it’s been solid. Keeps the engine running cool even on the hottest days no complaints here!

Jake M. - 05/21

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