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
-
Wrench Rabbit Engine Rebuild Kit 2002-2004 Honda CR250R WR101-015
WRENCH RABBIT
$870.40A two-stroke engine rebuild demands precision components that work together as a system—not mismatched parts that compromise reliability. This Wrench Rabbit kit eliminates guesswork by pairing...09030955- SKU:
- 09030955
- Availability:
- Ships Same Business Day
- Weight:
- 14.10 LBS
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- MODEL:
- WRENCH RABBIT
- ENGINE TYPE:
- 2-STROKE
- FEATURES:
- STANDARD COMPRESSION PISTON
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$870.40 -
Vertex Engine Rebuild Kit for 2016-2017 Honda CRF250R WR101-219
WRENCH RABBIT
$1,092.95When your Honda CRF250R's engine shows signs of wear—lost compression, increased blowby, or declining power delivery—a complete engine rebuild is the most cost-effective path to restored performance...09030959- SKU:
- 09030959
- Availability:
- Ships Same Business Day
- Weight:
- 12.70 LBS
- FEATURES:
- STANDARD COMPRESSION PISTON
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- WRENCH RABBIT
- PRODUCT NAME:
- REBUILD KIT
$1,092.95 -
WSM Top-End Rebuild Kit - Original Series - 1 mm 010-819-14
WSM
$330.79A complete top-end rebuild demands precision components that won't compromise engine integrity or performance. The WSM Original Series kit delivers OEM-quality pistons, rings, and bearings in one...09030122- SKU:
- 09030122
- Availability:
- Ships Same Business Day
- Weight:
- 4.15 LBS
- PRODUCT NAME:
- REBUILD KIT
- UNITS:
- EACH
- BORE SIZE METRIC:
- 88.91 MM
- MODEL:
- ORIGINAL SERIES
- RIDING STYLE:
- WATERCRAFT
- PISTON MATERIAL:
- ALUMINUM
- PISTON SIZE METRIC:
- +1.00 MM
- TYPE:
- TOP END
$330.79 -
WSM Top-End Rebuild Kit - Original Series - 1 mm 010-827-14
WSM
$241.36A top-end rebuild demands precision components that won't compromise your engine's reliability or performance. The WSM Original Series kit delivers OEM-quality pistons, rings, and bearings engineered...09030125- SKU:
- 09030125
- Availability:
- Ships Same Business Day
- Weight:
- 3.25 LBS
- BORE SIZE METRIC:
- 82.00 MM
- PISTON SIZE METRIC:
- +1.00 MM
- TYPE:
- TOP END
- MODEL:
- ORIGINAL SERIES
- RIDING STYLE:
- WATERCRAFT
- PISTON MATERIAL:
- ALUMINUM
- UNITS:
- EACH
- PRODUCT NAME:
- REBUILD KIT
$241.36Qty in Cart: 0Quantity:Price:$241.36Subtotal: -
On Sale
Wiseco Engine Rebuild Kit for 2002-2003 Kawasaki KX250 PWR128-100
WISECO
MSRP: $659.95Now: $561.00Was: $659.95When your KX250's engine has logged serious hours, a complete rebuild is the only path to restoring full power and reliability. The Wiseco PWR128-100 Engine Rebuild Kit gives you every critical...09031607- SKU:
- 09031607
- Availability:
- Ships Same Business Day
- Weight:
- 14.00 LBS
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- BORE SIZE METRIC:
- 66.40 MM
MSRP: $659.95Now: $561.00Was: $659.95Qty in Cart: 0Quantity:Price:MSRP: $659.95Now: $561.00Was: $659.95Subtotal: -
On Sale
Wiseco Engine Rebuild Kit for 2006 KTM 250 SX 66.40mm PWR179-100
WISECO
MSRP: $791.52Now: $706.00Was: $791.52When your 2-stroke 250cc engine shows signs of wear—loss of compression, sluggish throttle response, or visible carbon buildup—a complete rebuild is the most cost-effective path to restoring full...09031660- SKU:
- 09031660
- Availability:
- Ships Same Business Day
- Weight:
- 13.10 LBS
- PRODUCT NAME:
- REBUILD KIT
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 66.40 MM
MSRP: $791.52Now: $706.00Was: $791.52Qty in Cart: 0Quantity:Price:MSRP: $791.52Now: $706.00Was: $791.52Subtotal: -
On Sale
Wiseco Engine Rebuild Kit for KTM 300 XC 2008-2015 PWR238-101
WISECO
MSRP: $967.55Now: $822.00Was: $967.55A two-stroke engine rebuild demands precision components that can handle the demands of high-RPM operation, and the Wiseco PWR238-101 delivers exactly that. This comprehensive kit eliminates the...09031666- SKU:
- 09031666
- Availability:
- Ships Same Business Day
- Weight:
- 14.20 LBS
- PRODUCT NAME:
- REBUILD KIT
- RIDING STYLE:
- STREET
- TYPE:
- ENGINE
- BORE SIZE METRIC:
- 72.00 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $967.55Now: $822.00Was: $967.55 -
Vertex Complete Engine Rebuild Kit for Yamaha YZ250 2003-2025 WR101-082
WRENCH RABBIT
$911.35When your YZ250 two-stroke takes a beating on the track or trail, a complete engine rebuild demands precision components across every critical system. The Vertex Complete Engine Rebuild Kit...09031017- SKU:
- 09031017
- Availability:
- Ships Same Business Day
- Weight:
- 13.20 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- WRENCH RABBIT
- FEATURES:
- STANDARD COMPRESSION PISTON
$911.35 -
Wrench Rabbit Yamaha YZ250F 2003-2004 Complete Engine Rebuild Kit WR101-083
WRENCH RABBIT
$1,157.95When your YZ250F's engine has logged serious hours, a complete rebuild is the only way to restore original performance and reliability. The Wrench Rabbit complete engine rebuild kit eliminates the...09031018- SKU:
- 09031018
- Availability:
- Ships Same Business Day
- Weight:
- 13.05 LBS
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- WRENCH RABBIT
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- FEATURES:
- STANDARD COMPRESSION PISTON
- UNITS:
- KIT
$1,157.95 -
Wrench Rabbit Complete Engine Rebuild Kit for 2005-2007 Yamaha YZ250F WR101-084
WRENCH RABBIT
$1,157.95When your Yamaha YZ250F's engine reaches the end of its service life, a complete rebuild restores it to factory specifications and performance reliability. The Wrench Rabbit WR101-084 kit...09031019- SKU:
- 09031019
- Availability:
- Ships Same Business Day
- Weight:
- 13.25 LBS
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- WRENCH RABBIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- FEATURES:
- STANDARD COMPRESSION PISTON
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$1,157.95Qty in Cart: 0Quantity:Price:$1,157.95Subtotal: -
Wrench Rabbit Complete Engine Rebuild Kit for Yamaha YZ250F 2008-2013 WR101-085
WRENCH RABBIT
$1,157.95When your Yamaha YZ250F's engine reaches the end of its service life, a complete rebuild is the most cost-effective way to restore full performance and reliability. This Wrench Rabbit kit eliminates...09031020- SKU:
- 09031020
- Availability:
- Ships Same Business Day
- Weight:
- 13.25 LBS
- FEATURES:
- STANDARD COMPRESSION PISTON
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- WRENCH RABBIT
- UNITS:
- KIT
$1,157.95 -
Wrench Rabbit Complete Engine Rebuild Kit Yamaha YZ450F 2003-2005 WR101-086
WRENCH RABBIT
$1,183.95When your Yamaha YZ450F's engine shows signs of wear—whether from race-day abuse or high-mileage riding—a complete rebuild restores factory performance and reliability without the guesswork. The...09031021- SKU:
- 09031021
- Availability:
- Ships Same Business Day
- Weight:
- 15.30 LBS
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- WRENCH RABBIT
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- FEATURES:
- STANDARD COMPRESSION PISTON
- UNITS:
- KIT
$1,183.95 -
Wrench Rabbit Engine Kit Yamaha YZ125 1998-2000 WR101-093
WRENCH RABBIT
$1,272.55A seized or worn two-stroke engine doesn't just cost you track time—it threatens the reliability of your entire bike. The Wrench Rabbit Engine Kit gives you everything needed for a complete,...09031022- SKU:
- 09031022
- Availability:
- Ships Same Business Day
- Weight:
- 15.75 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- REBUILD KIT
- MODEL:
- WRENCH RABBIT
- TYPE:
- ENGINE
- FEATURES:
- STANDARD COMPRESSION PISTON
$1,272.55 -
Wrench Rabbit Engine Rebuild Kit for Yamaha YZ450F 2010-2013 WR101-088
WRENCH RABBIT
$1,249.95Whether you're recovering from a blown top-end or performing preventative maintenance, the Wrench Rabbit Engine Rebuild Kit gives you everything needed for a complete, professional-grade rebuild of...09031023- SKU:
- 09031023
- Availability:
- Ships Same Business Day
- Weight:
- 16.35 LBS
- MODEL:
- WRENCH RABBIT
- TYPE:
- ENGINE
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- REBUILD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- FEATURES:
- STANDARD COMPRESSION PISTON
$1,249.95 -
Wrench Rabbit Yamaha YZ85 2002-2016 Complete Engine Rebuild Kit WR101-089
WRENCH RABBIT
$564.95When a two-stroke engine reaches the end of its service life, a complete rebuild is your most cost-effective path back to peak performance. The Wrench Rabbit YZ85 kit consolidates everything you...09031024- SKU:
- 09031024
- Availability:
- Ships Same Business Day
- Weight:
- 8.05 LBS
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- WRENCH RABBIT
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- FEATURES:
- STANDARD COMPRESSION PISTON
$564.95 -
WSM Top-End Rebuild Kit - Original Series - .50 mm 010-817-12
WSM
$223.48A top-end rebuild demands precision components that can withstand extreme combustion pressures and maintain clearances across repeated heat cycles. The WSM Original Series kit eliminates guesswork by...09030035- SKU:
- 09030035
- Availability:
- Ships Same Business Day
- Weight:
- 3.25 LBS
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- TOP END
- UNITS:
- EACH
- BORE SIZE METRIC:
- 82.50 MM
- PISTON SIZE METRIC:
- +0.50 MM
- MODEL:
- ORIGINAL SERIES
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
$223.48 -
WSM Top-End Rebuild Kit - Original Series - Standard 010-817-10
WSM
$223.48A top-end rebuild demands precision components that restore your engine's compression, ring seal, and combustion efficiency to factory specifications—or better. The WSM Original Series kit delivers...09030034- SKU:
- 09030034
- Availability:
- Ships Same Business Day
- Weight:
- 3.20 LBS
- PRODUCT NAME:
- REBUILD KIT
- BORE SIZE METRIC:
- 82.00 MM
- PISTON SIZE METRIC:
- STANDARD
- TYPE:
- TOP END
- UNITS:
- EACH
- MODEL:
- ORIGINAL SERIES
- PISTON MATERIAL:
- ALUMINUM
- RIDING STYLE:
- WATERCRAFT
$223.48 -
WSM Top-End Rebuild Kit - Original Series - 1 mm 010-817-14
WSM
$223.48A top-end rebuild demands precision components that restore your engine to factory specifications or better. The WSM Original Series kit consolidates everything you need in one package—pistons,...09030036- 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
$250.31A top-end rebuild demands precision components that can withstand extreme combustion pressures and sustained RPM loads. The WSM Platinum Series kit eliminates the guesswork by pairing OEM-quality...09030744- 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
$250.31A complete top-end rebuild requires precision-matched components that work in concert—mismatched or worn parts will compromise compression, increase blow-by, and kill your power output. The WSM...09030745- 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
$250.31Qty in Cart: 0Quantity:Price:$250.31Subtotal:
