Dirt Bike Engine Rebuild Kits
Dirt Bike Engine Rebuild Kits for Kawasaki KX100, KTM XC-W 250 & Honda CRF250R at JJ Motorsports
Revive your dirt bike's engine to factory-fresh performance with premium rebuild kits from JJ Motorsports, featuring forged pistons, crankshafts, bearings, seals, and gaskets for superior compression, reduced vibration, and long-term reliability in motocross, enduro, and trail riding. Our selection includes complete top- and bottom-end kits designed for precise fitment, optimal oil flow, and enhanced power delivery without custom machining. Compatible with popular models like Kawasaki KX100, KTM XC/XC-W 250, Husqvarna TE250, and Honda CRF250R, these high-quality components from trusted brands ensure leak-free assembly, better heat management, and race-ready durability in dusty, high-RPM conditions. From Wiseco's comprehensive KX100 kits with hour meters to Vertex's all-in-one KTM rebuilds and Athena's high-performance CRF pistons, get everything needed for a pro-level refresh—pistons, rings, bearings, and gaskets—to restore throttle snap, efficiency, and confidence on every rip.
Shop brands like Wiseco, Vertex, and Athena for race-proven quality. Explore related categories such as dirt bike piston and ring kits for top-end focus or dirt bike engine for cylinders and valves.
Top Dirt Bike Engine Rebuild Kits
- Wiseco Engine Rebuild Kit 52.50 mm Kawasaki KX100 1995-2013 PWR173-100 – Comprehensive top- and bottom-end kit with high-quality crankshaft, rod assembly, main bearings, seals, gaskets, and hour meter bracket for Kawasaki KX100 models; ensures optimal performance and easy maintenance.
- VERTEX Engine Rebuild Kit - KTM XC/XC-W 250 | Husqvarna TE250 WR101-091 – All-in-one rebuild kit with Vertex piston, Hot Rods crankshaft, bearings/seals, transmission kit, and complete gaskets; perfect for professional top- and bottom-end refresh on KTM and Husqvarna 250cc models.
- ATHENA Piston Kit with Gaskets - 76.76 mm - CRF250R P5F0768245003B – High-performance 76.76 mm forged aluminum piston kit with rings, gaskets, and coatings for reduced friction; engineered for Honda CRF250R 4-stroke off-road with superior airflow and longevity.
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
-
WSM Top-End Rebuild Kit - Original Series - 1 mm 010-817-14
WSM
$223.48Top-quality piston kits, Include pistons, rings, pins, clips, racing needle bearings, head and base gaskets, intake and exhaust gaskets09030036- SKU:
- 09030036
- Availability:
- Ships Same Business Day
- Weight:
- 3.50 LBS
- PRODUCT NAME:
- REBUILD KIT
- BORE SIZE METRIC:
- 83.00 MM
- PISTON SIZE METRIC:
- +1.00 MM
- TYPE:
- TOP END
- UNITS:
- EACH
- MODEL:
- ORIGINAL SERIES
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
$223.48Qty in Cart: 0Quantity:Price:$223.48Subtotal: -
WSM Top-End Rebuild Kit - Platinum Series - .50 mm 010-808-12P
WSM
$250.31Top-quality piston kits, Include pistons, rings, pins, clips, racing needle bearings, head and base gaskets, intake and exhaust gaskets09030744- SKU:
- 09030744
- Availability:
- Ships Same Business Day
- Weight:
- 3.40 LBS
- PISTON SIZE METRIC:
- +0.50 MM
- PRODUCT NAME:
- REBUILD KIT
- MODEL:
- PLATINUM SERIES
- BORE SIZE METRIC:
- 82.50 MM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- TOP END
- UNITS:
- KIT
$250.31 -
WSM Top-End Rebuild Kit - Platinum Series - 1 mm 010-808-14P
WSM
$250.31Top-quality piston kits, Include pistons, rings, pins, clips, racing needle bearings, head and base gaskets, intake and exhaust gaskets09030745- SKU:
- 09030745
- Availability:
- Ships Same Business Day
- Weight:
- 3.40 LBS
- MODEL:
- PLATINUM SERIES
- PISTON SIZE METRIC:
- +1.00 MM
- TYPE:
- TOP END
- UNITS:
- EACH
- PRODUCT NAME:
- REBUILD KIT
- BORE SIZE METRIC:
- 83.00 MM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
$250.31 -
WSM Top-End Rebuild Kit - Platinum Series - Standard 010-809-10P
WSM
$339.74Top-quality piston kits, Include pistons, rings, pins, clips, racing needle bearings, head and base gaskets, intake and exhaust gaskets09030746- SKU:
- 09030746
- Availability:
- Ships Same Business Day
- Weight:
- 4.00 LBS
- PRODUCT NAME:
- REBUILD KIT
- MODEL:
- PLATINUM SERIES
- PISTON SIZE METRIC:
- STANDARD
- TYPE:
- TOP END
- UNITS:
- EACH
- BORE SIZE METRIC:
- 87.91 MM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
$339.74 -
WSM Top-End Rebuild Kit - Platinum Series - .50 mm 010-809-12P
WSM
$339.74Top-quality piston kits, Include pistons, rings, pins, clips, racing needle bearings, head and base gaskets, intake and exhaust gaskets09030747- SKU:
- 09030747
- Availability:
- Ships Same Business Day
- Weight:
- 4.10 LBS
- MODEL:
- PLATINUM SERIES
- TYPE:
- TOP END
- PRODUCT NAME:
- REBUILD KIT
- UNITS:
- EACH
- BORE SIZE METRIC:
- 88.41 MM
- PISTON SIZE METRIC:
- +0.50 MM
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
$339.74 -
On Sale
Wiseco Engine Rebuild Kit 66.40mm Bore Yamaha YZ250 2003-2020 PWR134-100
WISECO
MSRP: $654.95Now: $557.00Was: $654.95Revitalize your Yamaha YZ250/X with our comprehensive engine rebuild kit, meticulously crafted to enhance performance and reliability. This all-inclusive package ensures that every component, from the crankshaft to the gaskets, meets the highest...09031519- SKU:
- 09031519
- Availability:
- Ships Same Business Day
- Weight:
- 13.30 LBS
MSRP: $654.95Now: $557.00Was: $654.95 -
On Sale
ATHENA Piston Kit with Gaskets - 76.76 mm - CRF250R P5F0768245002B
ATHENA
MSRP: $203.95Now: $184.00Was: $203.95Piston Kit with Gaskets - 76.76 mm - CRF250R Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance, The smooth...09031703- SKU:
- 09031703
- Availability:
- Ships Same Business Day
- Weight:
- 1.08 LBS
MSRP: $203.95Now: $184.00Was: $203.95Qty in Cart: 0Quantity:Price:MSRP: $203.95Now: $184.00Was: $203.95Subtotal: -
On Sale
ATHENA Piston Kit with Gaskets - 76.96 mm - WR/YZ250F P5F0770039007A
ATHENA
MSRP: $222.95Now: $201.00Was: $222.95Piston Kit with Gaskets - 76.96 mm - P5F0770039007A High-performance aluminum alloy construction for enhanced durability. Designed for WR/YZ250F 4-stroke Off-Road motorcycles. Features a smooth profile for optimal flow and flame propagation...09031706- SKU:
- 09031706
- Availability:
- Ships Same Business Day
- Weight:
- 1.17 LBS
MSRP: $222.95Now: $201.00Was: $222.95 -
On Sale
ATHENA Piston Kit with Gaskets - 77.96 mm - EC250F | FE250 | 250EXCF P5F0780093001B
ATHENA
MSRP: $217.95Now: $196.00Was: $217.95Piston Kit with Gaskets - 77.96 mm - EC250F | FE250 | 250EXCF Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent...09031727- SKU:
- 09031727
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
MSRP: $217.95Now: $196.00Was: $217.95Qty in Cart: 0Quantity:Price:MSRP: $217.95Now: $196.00Was: $217.95Subtotal: -
On Sale
ATHENA Piston Kit with Gaskets - 78.95 mm - CRF250R/RX P5F0790319001A
ATHENA
MSRP: $212.95Now: $192.00Was: $212.95Piston Kit with Gaskets - 78.95 mm - CRF250R/RX Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance, The...09031728- SKU:
- 09031728
- Availability:
- Ships Same Business Day
- Weight:
- 1.21 LBS
MSRP: $212.95Now: $192.00Was: $212.95 -
On Sale
ATHENA Piston Kit with Gaskets - 71.93 mm - KTM P4C0720083002A
ATHENA
MSRP: $220.95Now: $199.00Was: $220.95Piston Kit with Gaskets - P4C0720083002A High-performance aluminum alloy with increased silicon content for enhanced durability. Designed to match OE piston reliability while offering superior resistance and performance. Optimized smooth profile for...09031774- SKU:
- 09031774
- Availability:
- Ships Same Business Day
- Weight:
- 1.57 LBS
MSRP: $220.95Now: $199.00Was: $220.95 -
On Sale
ATHENA Piston Kit with Gaskets - 71.94 mm - KTM P4C0720083002B
ATHENA
MSRP: $220.95Now: $199.00Was: $220.95Piston Kit with Gaskets - 71.94 mm - P4C0720083002B Constructed from high-performance aluminum alloy with elevated silicon content for enhanced durability. Designed to match the reliability of the original equipment (OE) piston while improving...09031775- SKU:
- 09031775
- Availability:
- Ships Same Business Day
- Weight:
- 1.54 LBS
MSRP: $220.95Now: $199.00Was: $220.95Qty in Cart: 0Quantity:Price:MSRP: $220.95Now: $199.00Was: $220.95Subtotal: -
On Sale
ATHENA Piston Kit with Gaskets - 66.35 mm - KTM P4C0664083001B
ATHENA
MSRP: $178.95Now: $161.00Was: $178.95Piston Kit with Gaskets - 66.35 mm - KTM Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance, The smooth...09031779- SKU:
- 09031779
- Availability:
- Ships Same Business Day
- Weight:
- 1.39 LBS
MSRP: $178.95Now: $161.00Was: $178.95 -
On Sale
ATHENA Piston Kit with Gaskets - 66.35 mm - KTM P4C0664045001B
ATHENA
MSRP: $178.95Now: $161.00Was: $178.95Piston Kit with Gaskets - 66.35 mm - P4C0664045001B High-performance aluminum alloy with high silicon content for enhanced durability. Designed to match OE piston reliability while improving resistance and performance. Smooth profile ensures...09031781- SKU:
- 09031781
- Availability:
- Ships Same Business Day
- Weight:
- 1.42 LBS
MSRP: $178.95Now: $161.00Was: $178.95 -
On Sale
ATHENA Piston Kit with Gaskets - 44.45 mm - Kawasaki P4C0445008001A
ATHENA
MSRP: $115.95Now: $104.00Was: $115.95Piston Kit with Gaskets - 44.45 mm - Kawasaki Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance, The...09031782- SKU:
- 09031782
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
MSRP: $115.95Now: $104.00Was: $115.95 -
On Sale
ATHENA Piston Kit with Gaskets - 44.46 mm - Kawasaki P4C0445008001B
ATHENA
MSRP: $115.95Now: $104.00Was: $115.95Piston Kit with Gaskets - 44.46 mm - Kawasaki Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance, The...09031783- SKU:
- 09031783
- Availability:
- Ships Same Business Day
- Weight:
- 0.77 LBS
MSRP: $115.95Now: $104.00Was: $115.95Qty in Cart: 0Quantity:Price:MSRP: $115.95Now: $104.00Was: $115.95Subtotal: -
On Sale
ATHENA Piston Kit with Gaskets - 53.96 mm - Yamaha P4C0540118014B
ATHENA
MSRP: $145.95Now: $131.00Was: $145.95Piston Kit with Gaskets - 53.96 mm - Yamaha Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance, The smooth...09031787- SKU:
- 09031787
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
MSRP: $145.95Now: $131.00Was: $145.95 -
On Sale
VERTEX Engine Rebuild Kit - Husqvarna | KTM WR00071
VERTEX
MSRP: $1,225.95Now: $1,103.36Was: $1,225.95Engine Rebuild Kit - Husqvarna | KTM Convenient one-stop shop in a box; nearly all components required for a complete and professional rebuild, Vertex piston kit (standard compression piston, rings, pin and clips), Hot Rods heavy-duty crank (stock stroke...09031805- SKU:
- 09031805
- Availability:
- Ships Same Business Day
- Weight:
- 14.54 LBS
MSRP: $1,225.95Now: $1,103.36Was: $1,225.95Qty in Cart: 0Quantity:Price:MSRP: $1,225.95Now: $1,103.36Was: $1,225.95Subtotal: -
On Sale
ATHENA Piston Kit with Gaskets - 95.98 mm - KX450F P5F0960072007B
ATHENA
MSRP: $263.07Now: $237.00Was: $263.07Piston Kit with Gaskets - 95.98 mm - KX450F Made of high-performance aluminum alloy with high silicon content that guarantee the same reliability of the OE piston, while at the same time providing greater resistance and excellent performance, The smooth...09031751- SKU:
- 09031751
- Availability:
- Ships Same Business Day
- Weight:
- 1.53 LBS
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- COMPRESSION RATIO IMPERIAL:
- 12.5:1
- TYPE:
- TOP END
- DISPLACEMENT:
- 450 CC
- MODEL:
- B
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 95.98 MM
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
MSRP: $263.07Now: $237.00Was: $263.07Qty in Cart: 0Quantity:Price:MSRP: $263.07Now: $237.00Was: $263.07Subtotal: -
On Sale
ATHENA Piston Kit with Gaskets - 87.95 mm - SXF350 P5F0880090001A
ATHENA
MSRP: $257.02Now: $231.00Was: $257.02Piston Kit with Gaskets - 87.95 mm - SXF350 High-performance aluminum alloy construction for enhanced durability. Designed for 4-stroke Off-Road motorcycles, ensuring optimal performance. Precision-engineered using CNC machines for...09031760- SKU:
- 09031760
- Availability:
- Ships Same Business Day
- Weight:
- 1.36 LBS
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- BORE SIZE METRIC:
- 87.95 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- 14.2:1
- DISPLACEMENT:
- 349 CC
- TYPE:
- TOP END
- MODEL:
- A
- PRODUCT NAME:
- PISTON KIT
MSRP: $257.02Now: $231.00Was: $257.02
