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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VINTCO Engine Gasket Kit - Yamaha KEG044
VINTCO
$36.95A failed gasket can compromise your engine's integrity and lead to costly downtime. The VINTCO Engine Gasket Kit KEG044 delivers complete lower-engine sealing with materials engineered to match or exceed OEM specifications, ensuring reliable performance...09347347- SKU:
- 09347347
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
$36.95 -
VINTCO Engine Gasket Kit - Yamaha KEG045
VINTCO
$34.95Engine gaskets degrade over time, leading to oil leaks, coolant seepage, and compromised combustion sealing—all of which rob your Yamaha of performance and reliability. The VINTCO KEG045 gasket kit replaces the entire lower engine assembly with...09347348- SKU:
- 09347348
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
$34.95 -
VINTCO Oil Seal Kit - Honda KOS005
VINTCO
$52.95A complete engine rebuild demands precision in every component, and sealing integrity is non-negotiable for oil retention and performance longevity. The VINTCO Oil Seal Kit ensures your Honda's lower end is properly sealed against leaks and...09347349- SKU:
- 09347349
- Availability:
- Ships Same Business Day
- Weight:
- 0.31 LBS
$52.95 -
VINTCO Oil Seal Kit - Honda KOS001
VINTCO
$36.95A complete engine rebuild demands meticulous attention to every seal and gasket—and this VINTCO Oil Seal Kit eliminates guesswork by including all the lower-end seals you need to prevent leaks and maintain pressure integrity. Whether you're refreshing a...09347350- SKU:
- 09347350
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
$36.95 -
VINTCO Oil Seal Kit - Honda KOS006
VINTCO
$45.95A complete engine rebuild demands precision at every sealing point—and this oil seal kit eliminates the guesswork by bundling all the critical lower-end seals your Honda engine requires. Factory seals degrade over time, leading to oil weeping,...09347351- SKU:
- 09347351
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
$45.95 -
VINTCO Oil Seal Kit - Kawasaki KOS016
VINTCO
$42.95A complete engine rebuild demands precision in every component—and oil seals are non-negotiable for preventing leaks and maintaining proper lubrication throughout your lower end. This VINTCO kit eliminates the guesswork by bundling all the critical seals...09347352- SKU:
- 09347352
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
$42.95 -
VINTCO Oil Seal Kit - Kawasaki KOS012
VINTCO
$42.95A complete engine rebuild demands precision sealing—any leak in your crankshaft, kickstarter, or clutch release shaft can compromise performance and reliability. The VINTCO Oil Seal Kit KOS012 supplies all the OEM-specification seals and o-rings you need...09347353- SKU:
- 09347353
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
$42.95 -
VINTCO Oil Seal Kit - Honda KOS002
VINTCO
$27.95A complete engine rebuild demands precision at every junction—and oil seals are where catastrophic leaks begin. The VINTCO Oil Seal Kit (KOS002) supplies all critical seals and o-rings for Honda lower-end assembly, eliminating the false economy of...09347354- SKU:
- 09347354
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$27.95 -
VINTCO Oil Seal Kit - Kawasaki KOS014
VINTCO
$42.95A complete engine rebuild demands precision sealing throughout the lower end—neglecting this step invites oil leakage, contamination, and premature wear on critical components. The VINTCO Oil Seal Kit delivers OEM-quality seals and o-rings engineered...09347355- SKU:
- 09347355
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
$42.95 -
VINTCO Oil Seal Kit - Honda KOS004
VINTCO
$31.95A proper engine rebuild demands precision sealing throughout the lower end—any compromise here leads to oil weeping, contamination, and premature wear. The VINTCO Oil Seal Kit delivers OEM-quality seals and o-rings engineered to maintain positive...09347356- SKU:
- 09347356
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$31.95 -
VINTCO Oil Seal Kit - Honda KOS007
VINTCO
$41.95A complete engine rebuild demands precision—and that starts with quality seals. The VINTCO Oil Seal Kit KOS007 provides all the critical seals and o-rings your Honda engine's lower end requires, eliminating the need to source components individually and...09347357- SKU:
- 09347357
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
$41.95Qty in Cart: 0Quantity:Price:$41.95Subtotal: -
VINTCO Oil Seal Kit - Honda KOS003
VINTCO
$27.95A complete engine rebuild demands precision sealing—any leak in your lower end will compromise compression and invite contamination into your oil system. This comprehensive seal kit eliminates the guesswork by bundling all critical seals and o-rings...09347358- SKU:
- 09347358
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$27.95 -
VINTCO Oil Seal Kit - Kawasaki KOS015
VINTCO
$42.95A complete engine rebuild demands precision at every seal point—and this VINTCO Oil Seal Kit eliminates the guesswork by bundling all the critical seals your Kawasaki engine needs in one package. Overlooking even a single oil seal during reassembly...09347359- SKU:
- 09347359
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
$42.95 -
VINTCO Oil Seal Kit - Kawasaki KOS017
VINTCO
$45.10A complete engine rebuild demands precision sealing at every critical junction, and this VINTCO Oil Seal Kit delivers exactly that for Kawasaki engines. Compromised seals lead to oil weeping, contamination, and accelerated wear—issues that undermine the...09347360- SKU:
- 09347360
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
$45.10Qty in Cart: 0Quantity:Price:$45.10Subtotal: -
VINTCO Oil Seal Kit - Kawasaki KOS013
VINTCO
$39.95A complete engine rebuild demands precision sealing to prevent oil leakage and maintain proper lubrication throughout your lower end. This VINTCO Oil Seal Kit delivers OEM-grade seals and o-rings engineered to factory specifications, ensuring your...09347361- SKU:
- 09347361
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
$39.95 -
Hinson Racing Clutch Cover Kawasaki KX450 2021-2023 C663-2102
HINSON RACING
$169.99Stock clutch covers on the KX450 will warp and lose efficiency under sustained track temperatures. This Hinson Racing cover dissipates heat more effectively, keeping your clutch engagement consistent lap after lap. Built from billet T-6 aircraft aluminum...09402038- SKU:
- 09402038
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
$169.99Qty in Cart: 0Quantity:Price:$169.99Subtotal: -
HOT RODS Crankshaft Assembly - OEM Stroke - Gas Gas | Husqvarna | KTM HR00125
HOT RODS
$531.95A crankshaft assembly is the heart of your engine's bottom end—it converts combustion force into rotational power. Hot Rods delivers OEM-stroke precision without compromise, factory-assembled and trued to exact specifications so you get reliability and...09210923- SKU:
- 09210923
- Availability:
- Ships Same Business Day
- Weight:
- 8.75 LBS
$531.95 -
On Sale
WISECO Piston Kit - 54.00 mm - Yamaha 899M05400
WISECO
MSRP: $155.95Now: $110.00Was: $155.95Stock pistons can't handle the demands of serious 2-stroke riding—they compromise on durability, throttle response, and peak horsepower. The WISECO 54.00 mm Piston Kit delivers a purpose-built solution with a dedicated forging design that optimizes...09106456- SKU:
- 09106456
- Availability:
- Ships Same Business Day
- Weight:
- 0.46 LBS
MSRP: $155.95Now: $110.00Was: $155.95 -
On Sale
Wiseco Piston Kit 54.00 mm Yamaha YZ125 2005-2021 846M05400
WISECO
MSRP: $199.95Now: $149.00Was: $199.95Stock pistons can't handle the demands of high-RPM riding or extended racing seasons—wear, carbon buildup, and power loss follow. The Wiseco 54.00 mm Piston Kit for your Yamaha YZ125 (2005-2021) delivers the durability and compression consistency you...09106458- SKU:
- 09106458
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
MSRP: $199.95Now: $149.00Was: $199.95Qty in Cart: 0Quantity:Price:MSRP: $199.95Now: $149.00Was: $199.95Subtotal: -
MOOSE RACING Snap Ring - 10 Pack - Gas Gas/Husqvarna/KTM 25-6014
MOOSE RACING
$24.95Front sprocket replacements demand precision fastening—and countershaft snap rings are easy to overlook until you need them. Keep this 10-pack of MOOSE Racing snap rings in your pit box or garage to eliminate downtime during maintenance. Individual...09351211- SKU:
- 09351211
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
$24.95
