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
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Wiseco Crankshaft Assembly with Bearings and Gasket for 2003-2012 Yamaha YZ250F WPC140
WISECO
$577.95If you're rebuilding a YZ250F bottom end, you need a crankshaft assembly that can handle the demands of consistent high-RPM operation without compromise. The Wiseco WPC140 delivers factory-grade...09210098- SKU:
- 09210098
- Availability:
- Ships Same Business Day
- Weight:
- 8.65 LBS
- STROKE LENGTH METRIC:
- 53.60 MM
- TYPE:
- BOTTOM END
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- FEATURES:
- INCLUDES BEARING AND GASKET
- MATERIAL:
- STEEL
$577.95Qty in Cart: 0Quantity:Price:$577.95Subtotal: -
Wiseco Yamaha YZ80 1993-2001 Crankshaft Kit WPC122
WISECO
$343.95A worn or failing crankshaft will tank your YZ80's reliability and power delivery—this Wiseco kit gives you a factory-assembled, precision-engineered replacement that meets OEM specifications and...09210101- SKU:
- 09210101
- Availability:
- Ships Same Business Day
- Weight:
- 6.24 LBS
- FEATURES:
- INCLUDES BEARING AND GASKET
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 47.80 MM
- TYPE:
- BOTTOM END
- UNITS:
- KIT
$343.95 -
Wiseco Crankshaft Assembly with Bearings and Gasket for 2001-2002 Yamaha YZ250 WPC127
WISECO
$477.95A worn or damaged crankshaft will cripple your YZ250's power delivery and reliability on the track. The Wiseco WPC127 assembly delivers factory-spec precision with OEM-matched tolerances, so you get...09210102- SKU:
- 09210102
- Availability:
- Ships Same Business Day
- Weight:
- 12.30 LBS
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- FEATURES:
- INCLUDES BEARING AND GASKET
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 72.00 MM
- TYPE:
- BOTTOM END
- UNITS:
- KIT
$477.95 -
Wiseco Crankshaft Assembly with Bearings and Gasket for 1999-2000 Yamaha YZ250 WPC126
WISECO
$477.95A worn or damaged crankshaft compromises your YZ250's bottom-end reliability and power delivery—especially critical if you're pushing hard at the track or trail. This Wiseco complete assembly...09210104- SKU:
- 09210104
- Availability:
- Ships Same Business Day
- Weight:
- 12.18 LBS
- STROKE LENGTH METRIC:
- 72.00 MM
- FEATURES:
- INCLUDES BEARING AND GASKET
- PRODUCT NAME:
- CRANKSHAFT ASSEMBLY
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- BOTTOM END
- UNITS:
- KIT
$477.95Qty in Cart: 0Quantity:Price:$477.95Subtotal: -
Wiseco Crankshaft Kit for 2006-2009 Yamaha YZ450F WPC151
WISECO
$624.95A crankshaft is the foundation of engine reliability and performance—when it fails, your entire engine fails. The Wiseco Crankshaft Kit for 2006-2009 Yamaha YZ450F delivers factory-matched precision...09210432- SKU:
- 09210432
- Availability:
- Ships Same Business Day
- Weight:
- 12.27 LBS
- PRODUCT NAME:
- CRANKSHAFT KIT
- FEATURES:
- INCLUDES BEARING AND GASKET
- TYPE:
- BOTTOM END
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- STROKE LENGTH METRIC:
- 63.40 MM
- UNITS:
- KIT
$624.95Qty in Cart: 0Quantity:Price:$624.95Subtotal: -
Wiseco Crankshaft Kit with Gasket 2001-2015 KTM 125 SX WPC153
WISECO
$621.95A crankshaft failure leaves you sidelined. The Wiseco WPC153 kit delivers a complete bottom-end solution—crankshaft, bearings, gaskets, and seals all precision-assembled to OEM specs—so you can...09210434- SKU:
- 09210434
- Availability:
- Ships Same Business Day
- Weight:
- 9.97 LBS
- FEATURES:
- INCLUDES BEARING AND GASKET
- PRODUCT NAME:
- CRANKSHAFT KIT
- TYPE:
- BOTTOM END
- MATERIAL:
- STEEL
- STROKE LENGTH METRIC:
- 54.50 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$621.95 -
Wiseco Engine Rebuild Kit for 1992-1996 Honda CR250R PWR101-100
WISECO
$688.95A top-end rebuild won't cut it if your CR250R's bottom end is wearing out. The Wiseco PWR101-100 gives you everything needed for a complete engine overhaul—pistons, crankshaft, bearings, and seals—so...09031596- SKU:
- 09031596
- Availability:
- Ships Same Business Day
- Weight:
- 14.10 LBS
- BORE SIZE METRIC:
- 66.40 MM
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$688.95Qty in Cart: 0Quantity:Price:$688.95Subtotal: -
Wiseco Engine Rebuild Kit for Honda CR125R 1992-1997 PWR116A-101
WISECO
$549.95Whether you're rebuilding a worn CR125R or preparing for serious competition, a quality engine rebuild kit is non-negotiable. The Wiseco PWR116A-101 delivers OEM-grade components and premium upgrades...09031600- SKU:
- 09031600
- Availability:
- Ships Same Business Day
- Weight:
- 10.00 LBS
- BORE SIZE METRIC:
- 54.00 MM
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- BORE - OVERSIZE:
- STANDARD
- BORE - OVERSIZE METRIC:
- STANDARD
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$549.95Qty in Cart: 0Quantity:Price:$549.95Subtotal: -
Wiseco Engine Rebuild Kit for Honda CR125R 2001-2002 PWR116A-104
WISECO
$554.95A top-end rebuild can only take your CR125 so far—a complete engine refresh with quality components is what separates reliable race machines from unreliable ones. The Wiseco PWR116A-104 kit provides...09031496- SKU:
- 09031496
- Availability:
- Ships Same Business Day
- Weight:
- 4.35 LBS
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 125 CC
- OVERBORE METRIC:
- STANDARD
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- FEATURES:
- PROLITE® PISTON
- UNITS:
- KIT
$554.95Qty in Cart: 0Quantity:Price:$554.95Subtotal: -
Wiseco Engine Kit for Kawasaki KX65 2000-2005 PWR117-100
WISECO
$499.95A complete engine rebuild demands precision components that won't compromise reliability or performance. The Wiseco Engine Kit for KX65 delivers a full top and bottom-end overhaul with rigorously...09031497- SKU:
- 09031497
- Availability:
- Ships Same Business Day
- Weight:
- 7.40 LBS
- DISPLACEMENT:
- 65 CC
- ENGINE TYPE:
- 2-STROKE
- FEATURES:
- STANDARD PISTON
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 44.50 MM
- OVERBORE METRIC:
- STANDARD
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$499.95Qty in Cart: 0Quantity:Price:$499.95Subtotal: -
Wiseco Engine Rebuild Kit Kawasaki KX100 1998-2005 PWR119-102
WISECO
$532.95When your KX100's engine reaches the end of its service life, a complete rebuild using OEM-quality components is the most cost-effective path to restored reliability and performance. The Wiseco...09031499- SKU:
- 09031499
- Availability:
- Ships Same Business Day
- Weight:
- 8.00 LBS
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 52.50 MM
- FEATURES:
- PROLITE® PISTON
- OVERBORE METRIC:
- STANDARD
- DISPLACEMENT:
- 100 CC
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$532.95 -
Wiseco Engine Rebuild Kit Kawasaki KX85 2001-2005 PWR119-104
WISECO
$499.95When your KX85's engine shows signs of wear—loss of compression, excessive blow-by, or simply tired performance—a full rebuild using OEM-quality components is the most cost-effective path back to...09031500- SKU:
- 09031500
- Availability:
- Ships Same Business Day
- Weight:
- 1.20 LBS
- TYPE:
- ENGINE
- FEATURES:
- PROLITE® PISTON
- OVERBORE METRIC:
- STANDARD
- PRODUCT NAME:
- REBUILD KIT
- DISPLACEMENT:
- 85 CC
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 48.50 MM
$499.95Qty in Cart: 0Quantity:Price:$499.95Subtotal: -
Wiseco Engine Rebuild Kit for 2001-2003 Suzuki RM125 PWR121-100
WISECO
$588.95A worn RM125 engine loses compression, power, and reliability—and a full rebuild is the only way to restore it to factory spec. The Wiseco PWR121-100 kit eliminates the guesswork by bundling all...09031501- SKU:
- 09031501
- Availability:
- Ships Same Business Day
- Weight:
- 10.30 LBS
- DISPLACEMENT:
- 125 CC
- FEATURES:
- PROLITE® PISTON
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 54.00 MM
- OVERBORE METRIC:
- STANDARD
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$588.95Qty in Cart: 0Quantity:Price:$588.95Subtotal: -
Wiseco Engine Rebuild Kit Yamaha YZ85 2002-2018 PWR123-100
WISECO
$499.95When your YZ85's engine has logged serious hours on the track or trail, a complete rebuild with OEM-quality components is the only way to restore full power and reliability. The Wiseco Engine Rebuild...09031503- SKU:
- 09031503
- Availability:
- Ships Same Business Day
- Weight:
- 7.60 LBS
- FEATURES:
- PROLITE® PISTON
- OVERBORE METRIC:
- STANDARD
- BORE SIZE METRIC:
- 47.50 MM
- DISPLACEMENT:
- 85 CC
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$499.95 -
Wiseco Engine Rebuild Kit for 2001 Yamaha YZ125 PWR125-100
WISECO
$588.95When your YZ125's engine has logged serious hours, a complete rebuild is the only way to restore reliability and reclaim the performance you expect from your bike. This Wiseco kit delivers everything...09031505- SKU:
- 09031505
- Availability:
- Ships Same Business Day
- Weight:
- 9.85 LBS
- BORE SIZE METRIC:
- 54.00 MM
- OVERBORE METRIC:
- STANDARD
- FEATURES:
- PROLITE® PISTON
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- DISPLACEMENT:
- 125 CC
- ENGINE TYPE:
- 2-STROKE
$588.95Qty in Cart: 0Quantity:Price:$588.95Subtotal: -
Wiseco Engine Rebuild Kit Yamaha YZ125 2003-2004 PWR125-102
WISECO
$588.95A complete engine rebuild isn't just maintenance—it's the foundation of consistent power delivery and reliability when you need it most. The Wiseco PWR125-102 kit gives you everything required for a...09031507- SKU:
- 09031507
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- ENGINE TYPE:
- 2-STROKE
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 54.00 MM
- DISPLACEMENT:
- 125 CC
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
- FEATURES:
- PROLITE® PISTON
- OVERBORE METRIC:
- STANDARD
- UNITS:
- KIT
$588.95Qty in Cart: 0Quantity:Price:$588.95Subtotal: -
Wiseco Engine Rebuild Kit Yamaha YZ250 1999-2000 PWR126-100
WISECO
$710.95A YZ250 engine rebuild demands precision components that can withstand the demands of competitive riding. This Wiseco kit eliminates guesswork by bundling OEM-spec crankshaft and rod assemblies with...09031508- SKU:
- 09031508
- Availability:
- Ships Same Business Day
- Weight:
- 13.40 LBS
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE SIZE METRIC:
- 66.40 MM
- FEATURES:
- PROLITE® PISTON
- OVERBORE METRIC:
- STANDARD
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- ENGINE
$710.95Qty in Cart: 0Quantity:Price:$710.95Subtotal: -
Wiseco Engine Rebuild Kit Yamaha YZ250 2001 PWR127-100
WISECO
$710.95When your YZ250's engine shows signs of wear—loss of compression, increased blow-by, or inconsistent power delivery—a complete rebuild restores the bike to factory performance standards. The Wiseco...09031509- SKU:
- 09031509
- Availability:
- Ships Same Business Day
- Weight:
- 13.40 LBS
- PRODUCT NAME:
- REBUILD KIT
- DISPLACEMENT:
- 250 CC
- ENGINE TYPE:
- 2-STROKE
- TYPE:
- ENGINE
- BORE SIZE METRIC:
- 66.40 MM
- FEATURES:
- PROLITE® PISTON
- OVERBORE METRIC:
- STANDARD
- MODEL:
- GARAGE BUDDY
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$710.95 -
Wiseco Engine Rebuild Kit Honda CRF450R 2002-2006 PWR138-100
WISECO
$977.95When your CRF450R's engine shows signs of wear—whether from track abuse, high-mileage riding, or competitive use—a full rebuild is the most cost-effective path to restoring performance and...09031524- SKU:
- 09031524
- Availability:
- Ships Same Business Day
- Weight:
- 15.40 LBS
$977.95Qty in Cart: 0Quantity:Price:$977.95Subtotal: -
Wiseco Engine Rebuild Kit for 2007 Honda CRF450R PWR138-101
WISECO
$977.95When your CRF450R's engine reaches the end of its service life, a complete rebuild is your most cost-effective path back to reliable performance. The Wiseco Engine Rebuild Kit PWR138-101 eliminates...09031525- SKU:
- 09031525
- Availability:
- Ships Same Business Day
- Weight:
- 15.05 LBS
$977.95
