Dirt Bike Engine
Dirt Bike Engine Parts at JJ Motorsports
Discover a full range of dirt bike engine components for rebuilding or upgrading your performance from JJ Motorsports. From crankshafts to cylinder heads and piston kits, these precision-engineered components ensure reliable performance. For additional upgrades, check out our full selection of off-road dirt bike parts to keep your engine running at peak efficiency on the track or trails.
Shop trusted brands like Wiseco for forged piston kits and K&N for high-flow oil filters. Explore related categories such as Dirt Bike Air and Fuel for intake upgrades or Dirt Bike Exhaust for complete systems.
Browse our in-stock inventory below with same-day shipping and expert support. Questions? Contact us for fitment advice!
- Product
- Qty in Cart
- Quantity
- Price
- Subtotal
-
VERTEX Piston Kit 24243B
VERTEX
$164.95The VERTEX Piston Kit 24243B delivers the reliability and precision your engine demands, whether you're pushing peak RPMs on the track or fine-tuning your build in the garage. Engineered with advanced metallurgy and surface treatments, these pistons are...09105160- SKU:
- 09105160
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- DISPLACEMENT:
- 125 CC
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- STREET
- STYLE:
- CAST RACE
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.00 MM
- PISTON MATERIAL:
- CAST
- UNITS:
- KIT
- PISTON DIAMETER METRIC:
- 53.95 MM
- PRODUCT NAME:
- PISTON KIT
$164.95 -
Wossner Piston Kit 8656DA for Honda CRF250R 2006-2009
WOSSNER
$184.00Stock pistons can't handle the sustained heat and load demands of racing or high-performance riding. The Wossner 8656DA delivers the durability and precision you need to push your CRF250R to its limits without sacrificing reliability. Whether you're...09104960- SKU:
- 09104960
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- UNITS:
- KIT
- BORE SIZE METRIC:
- 78.00 MM
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- PRO SERIES
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- 77.96 MM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- PISTON MATERIAL:
- FORGED
$184.00 -
Wossner Dual Ring Piston Kit KTM 250 2005-2025 8169DB
WOSSNER
$152.00The Wossner 8169DB piston kit delivers the reliability and precision required for sustained high-rpm performance in your KTM 250 2-stroke. Factory-engineered with 4032 T6 forged aluminum and a permanent friction-reducing skirt coating, this kit minimizes...09104862- SKU:
- 09104862
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE:
- +0,01 MM
- BORE - OVERSIZE METRIC:
- +0.01 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- PISTON SIZE METRIC:
- 66.35 MM
- BORE SIZE METRIC:
- 66.41 MM
- DISPLACEMENT:
- 249 CC
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
$152.00 -
Wossner Piston Kit KTM 250 SX 2005-2020 8169DA
WOSSNER
$152.00The KTM 250 SX demands a piston that can withstand extreme combustion pressures and sustained high RPMs without compromising reliability. Wossner's 8169DA kit delivers exactly that—a German-engineered piston assembly built from 4032 T6 forged aluminum...09104861- SKU:
- 09104861
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- MODEL:
- STANDARD SERIES
- PISTON SIZE METRIC:
- 66.34 MM
- PRODUCT NAME:
- PISTON KIT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 66.40 MM
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- DISPLACEMENT:
- 249 CC
- TYPE:
- DUAL RING
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
$152.00Qty in Cart: 0Quantity:Price:$152.00Subtotal: -
Wossner Yamaha YZ125 2005-2019 53.97mm Piston Kit 8160DC
WOSSNER
$122.00When you're pushing a YZ125 to its limits, piston durability and ring seal integrity directly impact throttle response, engine longevity, and race-day reliability. Wossner's 8160DC kit is engineered to handle the thermal and mechanical demands of...09104855- SKU:
- 09104855
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- DISPLACEMENT:
- 124 CC
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- 53.97 MM
- RIDING STYLE:
- OFF-ROAD
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- TYPE:
- SINGLE RING
- BORE - OVERSIZE:
- +0,02 MM
- BORE - OVERSIZE METRIC:
- +0.02 MM
- BORE SIZE METRIC:
- 54.02 MM
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
$122.00Qty in Cart: 0Quantity:Price:$122.00Subtotal: -
Wossner Piston Kit Kawasaki KX250 2002-2004 66.34mm 8088DA
WOSSNER
$152.00The Wossner 8088DA piston kit is engineered for KX250 riders who demand reliable power delivery and engine longevity. A complete OEM-quality replacement, this kit eliminates guesswork with matched components designed to work together seamlessly. If...09104809- SKU:
- 09104809
- Availability:
- Ships Same Business Day
- Weight:
- 0.70 LBS
- BORE SIZE METRIC:
- 66.40 MM
- PISTON SIZE METRIC:
- 66.34 MM
- DISPLACEMENT:
- 249 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
- BORE - OVERSIZE METRIC:
- STANDARD
- MODEL:
- STANDARD SERIES
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE:
- STANDARD
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
$152.00 -
Wossner Piston Kit Suzuki RM250 2003-2010 8086DC
WOSSNER
$122.00The Wössner Piston Kit 8086DC is engineered to restore or enhance your RM250's performance with precision-manufactured internals that reduce friction and extend engine life. Built from 4032 T6 forged aluminum and finished with a permanent skirt coating,...09104808- SKU:
- 09104808
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- ENGINE TYPE:
- 2-STROKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +0.02 MM
- PISTON SIZE METRIC:
- 66.36 MM
- BORE SIZE METRIC:
- 66.42 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE:
- +0,02 MM
- DISPLACEMENT:
- 249 CC
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
$122.00Qty in Cart: 0Quantity:Price:$122.00Subtotal: -
Wossner Suzuki RM250 2003-2010 Piston Kit 8086DB
WOSSNER
$122.00The Wossner RM250 piston kit delivers the reliability and durability that 2-stroke racers demand, whether you're pushing hard on the track or maintaining peak performance in the dirt. Factory OEM pistons wear out—this kit replaces them with...09104807- SKU:
- 09104807
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- +0,01 MM
- BORE - OVERSIZE METRIC:
- +0.01 MM
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- BORE SIZE METRIC:
- 66.41 MM
- DISPLACEMENT:
- 249 CC
- PISTON SIZE METRIC:
- 66.35 MM
- TYPE:
- DUAL RING
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
$122.00Qty in Cart: 0Quantity:Price:$122.00Subtotal: -
On Sale
ATHENA Piston Kit S4F08100005B
ATHENA
MSRP: $293.95Now: $265.00Was: $293.95A high-quality piston kit is essential for maintaining engine performance and reliability, whether you're rebuilding after wear or upgrading for increased displacement. The ATHENA Piston Kit S4F08100005B delivers OEM-equivalent precision with all...09104194- SKU:
- 09104194
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- PISTON DIAMETER METRIC:
- 80.96 MM
- PISTON SIZE METRIC:
- STANDARD SIZE B
- COMPRESSION RATIO IMPERIAL:
- 13.6:1
- PRODUCT NAME:
- PISTON
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- BIG BORE
- ENGINE TYPE:
- 4-STROKE
- UNITS:
- EACH
MSRP: $293.95Now: $265.00Was: $293.95 -
On Sale
ATHENA Piston Kit S4F08100005A
ATHENA
MSRP: $293.95Now: $265.00Was: $293.95A quality piston kit is the foundation of reliable engine performance, directly affecting compression ratio, combustion efficiency, and overall durability under load. The ATHENA Piston Kit S4F08100005A delivers OEM-specification engineering with...09104193- SKU:
- 09104193
- Availability:
- Ships Same Business Day
- Weight:
- 0.67 LBS
- COMPRESSION RATIO IMPERIAL:
- 13.6:1
- PISTON DIAMETER METRIC:
- 80.95 MM
- PRODUCT NAME:
- PISTON
- STYLE:
- BIG BORE
- PISTON SIZE METRIC:
- STANDARD SIZE A
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
MSRP: $293.95Now: $265.00Was: $293.95 -
Wiseco Piston Kit Kawasaki KLX650 1993-1995 9.5:1 Compression 40133M10000
WISECO
$239.95When your KLX650's piston shows wear or you're ready to unlock higher compression performance, a quality rebuild kit is essential to maintaining reliability and power delivery. Wiseco's forged piston design combines durability with a responsive 9.5:1...09103949- SKU:
- 09103949
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON
- STROKE LENGTH METRIC:
- 82.00 MM
- UNITS:
- EACH
- BORE SIZE METRIC:
- 100.00 MM
- COMPRESSION RATIO IMPERIAL:
- 9.5:1
- DISPLACEMENT:
- 644 CC
- PISTON MATERIAL:
- FORGED
- RIDING STYLE:
- STREET
$239.95Qty in Cart: 0Quantity:Price:$239.95Subtotal: -
VERTEX Piston Kit 23647A
VERTEX
$289.95A high-performance piston kit demands precision engineering and durability that goes beyond standard OEM specs. The VERTEX Piston Kit 23647A delivers the thermal stability and low-friction characteristics needed for sustained high-RPM operation and...09102572- SKU:
- 09102572
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- COMPRESSION RATIO IMPERIAL:
- 13.9:1
- CYLINDER DIAMETER METRIC:
- 77.00 MM
- PISTON DIAMETER METRIC:
- 76.95 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- FORGED HIGH COMPRESSION
- UNITS:
- KIT
- DISPLACEMENT:
- 250 CC
- PRODUCT NAME:
- PISTON KIT
$289.95 -
VERTEX Piston Kit 23599B
VERTEX
$271.95Whether 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 -
VERTEX Piston Kit 23457B
VERTEX
$260.95A 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
$260.95Qty in Cart: 0Quantity:Price:$260.95Subtotal: -
On Sale
ATHENA Piston Kit S4F100000190
ATHENA
MSRP: $257.95Now: $232.00Was: $257.95Engine 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: $257.95Now: $232.00Was: $257.95 -
On Sale
ATHENA Piston Kit S4F04700001A
ATHENA
MSRP: $142.95Now: $129.00Was: $142.95When 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: $142.95Now: $129.00Was: $142.95Qty in Cart: 0Quantity:Price:MSRP: $142.95Now: $129.00Was: $142.95Subtotal: -
On Sale
ATHENA Piston Kit S4F04500001A
ATHENA
MSRP: $142.95Now: $129.00Was: $142.95Maximum 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: $142.95Now: $129.00Was: $142.95 -
VERTEX Piston Kit 23378B
VERTEX
$271.95Whether 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 -
VERTEX Piston Kit 23198B
VERTEX
$289.95The 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 -
VERTEX Piston Kit - Standard 22521B
VERTEX
$235.95A 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
$235.95Qty in Cart: 0Quantity:Price:$235.95Subtotal:
