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
-
LA Sleeve KX85 2001-2013 Sleeve and Piston Kit LAS-5449K-1
LA SLEEVE
$312.95Revitalize your Kawasaki's performance with the LA SLEEVE Sleeve and Piston Kit. This comprehensive top-end rebuild kit is engineered for maximum efficiency, featuring advanced materials and precision design to enhance power and reliability. Experience...09310415- SKU:
- 09310415
- Availability:
- Ships Same Business Day
- Weight:
- 1.46 LBS
- MATERIAL:
- CAST
- PRODUCT NAME:
- REBUILD KIT
- MATERIAL:
- IRON
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CYLINDER
- UNITS:
- KIT
$312.95Qty in Cart: 0Quantity:Price:$312.95Subtotal: -
LA Sleeve Cylinder Rebuild Kit for 2002-2003 Kawasaki KX250 LAS-5471K
LA SLEEVE
$422.95Elevate your Kawasaki's performance with the LA SLEEVE Sleeve and Piston Kit. Designed for optimal efficiency, this comprehensive top-end rebuild kit ensures enhanced compression, increased torque, and greater horsepower. Featuring advanced materials and...09310416- SKU:
- 09310416
- Availability:
- Ships Same Business Day
- Weight:
- 3.00 LBS
- TYPE:
- CYLINDER
- UNITS:
- KIT
- MATERIAL:
- IRON
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- CAST
- PRODUCT NAME:
- REBUILD KIT
$422.95 -
LA Sleeve Suzuki RM85 2002-2021 Sleeve and Piston Kit LAS-5479K
LA SLEEVE
$312.95Enhance your Suzuki's performance with the LA SLEEVE Sleeve and Piston Kit. This all-in-one top-end rebuild kit is engineered for superior efficiency and power, featuring advanced materials that ensure optimal ring seal and increased horsepower. Perfect...09310417- SKU:
- 09310417
- Availability:
- Ships Same Business Day
- Weight:
- 1.16 LBS
- MATERIAL:
- CAST
- PRODUCT NAME:
- REBUILD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- IRON
- TYPE:
- CYLINDER
$312.95 -
LA SLEEVE Cylinder Sleeve Yamaha XT225 2001-2007 YA5631
LA SLEEVE
$93.95Revitalize your engine with the LA SLEEVE Cylinder Sleeve YA5631, designed for exceptional performance and durability. This high-quality replacement sleeve ensures a perfect fit, restoring your cylinder's functionality and extending its lifespan. Upgrade...09310572- SKU:
- 09310572
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- BORE SIZE METRIC:
- 70.00 MM
- COLOR/FINISH:
- CHROME
- UNITS:
- EACH
- PRODUCT NAME:
- CYLINDER SLEEVE
- RIDING STYLE:
- OFF-ROAD
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
- TYPE:
- AC
$93.95 -
On Sale
L.A. Sleeve Cylinder Sleeve for Honda Pioneer 700 2016-2024 H5621
LA SLEEVE
MSRP: $127.95Now: $82.00Was: $127.95Revitalize your engine's performance with the LA SLEEVE Cylinder Sleeve H5621. Designed for durability and precision, this high-quality replacement sleeve ensures a perfect fit and enhances the longevity of your cylinders. Experience improved efficiency...09310642- SKU:
- 09310642
- Availability:
- Ships Same Business Day
- Weight:
- 1.70 LBS
- BORE SIZE METRIC:
- 102.00 MM
- COLOR/FINISH:
- ALUMINUM
- RIDING STYLE:
- UTV
- PRODUCT NAME:
- CYLINDER SLEEVE
- TYPE:
- CI
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
MSRP: $127.95Now: $82.00Was: $127.95 -
LA Sleeve Cylinder Sleeve for Yamaha Grizzly 450 2007-2014 Kodiak 450 2003-2024 Rhino 450 2006-2010 Wolverine 450 2006-2022 YA5513
LA SLEEVE
$104.95Revitalize your engine with the LA SLEEVE Cylinder Sleeve YA5513, designed for optimal performance and durability. This high-quality replacement sleeve is engineered to restore old cylinders, ensuring reliable operation and extended engine life...09310645- SKU:
- 09310645
- Availability:
- Ships Same Business Day
- Weight:
- 1.96 LBS
- BORE SIZE METRIC:
- 84.50 MM
- RIDING STYLE:
- UTV
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
- PRODUCT NAME:
- CYLINDER SLEEVE
- TYPE:
- RS
- COLOR/FINISH:
- ALUMINUM
- RIDING STYLE:
- ATV
- UNITS:
- EACH
$104.95 -
LA Sleeve Cylinder Sleeve 47mm KTM 85 SX 2003-2017 FL5551
LA SLEEVE
$117.95Revitalize your engine with the LA SLEEVE Cylinder Sleeve FL5551, designed for optimal performance and durability. These high-quality replacement sleeves ensure a perfect fit, extending the life of your engine while maintaining efficiency. Upgrade your...09310516- SKU:
- 09310516
- Availability:
- Ships Same Business Day
- Weight:
- 0.61 LBS
- BORE SIZE METRIC:
- 100.00 MM
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
- TYPE:
- AC
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- COLOR/FINISH:
- CHROME
- PRODUCT NAME:
- CYLINDER SLEEVE
$117.95Qty in Cart: 0Quantity:Price:$117.95Subtotal: -
LA Sleeve 2003-2014 KTM 200 EXC Sleeve and Piston Kit LAS-5554K
LA SLEEVE
$422.95Revitalize your KTM with the LA SLEEVE Sleeve and Piston Kit, designed for optimal performance and durability. This all-in-one top-end rebuild kit ensures enhanced compression, increased torque, and a boost in horsepower, making it an essential upgrade...09310520- SKU:
- 09310520
- Availability:
- Ships Same Business Day
- Weight:
- 2.05 LBS
- MATERIAL:
- CAST
- MATERIAL:
- IRON
- TYPE:
- CYLINDER
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- REBUILD KIT
$422.95Qty in Cart: 0Quantity:Price:$422.95Subtotal: -
LA Sleeve Cylinder Sleeve 90mm Bore Honda TRX450FE 1998-2004 H5365
LA SLEEVE
$117.95If your Honda TRX450FE is showing signs of cylinder wear—rough idle, loss of compression, or increased oil consumption—a quality cylinder sleeve is your path back to factory performance. The LA SLEEVE H5365 restores your engine's structural integrity...H5365- SKU:
- H5365
- Availability:
- Ships Same Business Day
- Weight:
- 2.20 LBS
- BORE SIZE METRIC:
- 90.00 MM
- TYPE:
- RS
- COLOR/FINISH:
- ALUMINUM
- PRODUCT NAME:
- CYLINDER SLEEVE
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
$117.95 -
LA Sleeve Sleeve and Piston Kit Honda TRX450ES 1998-2004 LAS-5365K
LA SLEEVE
$328.95When your Honda TRX450ES shows signs of wear—reduced compression, loss of throttle response, or visible blow-by—a top-end rebuild becomes essential to restore original performance. The LA Sleeve Sleeve and Piston Kit delivers a complete, bolt-together...09310359- SKU:
- 09310359
- Availability:
- Ships Same Business Day
- Weight:
- 4.20 LBS
- TYPE:
- CYLINDER
- UNITS:
- KIT
- PRODUCT NAME:
- REBUILD KIT
- MATERIAL:
- IRON
- RIDING STYLE:
- ATV
$328.95 -
LA Sleeve Cylinder Sleeve Honda TRX500FE 2005-2009 H5591
LA SLEEVE
$117.95Worn cylinder walls reduce compression, kill throttle response, and compromise your TRX500FE's reliability in the field or on the track. The LA Sleeve H5591 restores factory bore integrity, allowing your engine to build proper pressure and deliver...09310711- SKU:
- 09310711
- Availability:
- Ships Same Business Day
- Weight:
- 2.55 LBS
- BORE SIZE METRIC:
- 92.00 MM
- COLOR/FINISH:
- ALUMINUM
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
- PRODUCT NAME:
- CYLINDER SLEEVE
- TYPE:
- RS
$117.95 -
LA Sleeve Cylinder Sleeve for Polaris General 1000 2016-2017 FL5777
LA SLEEVE
$117.95When your Polaris General 1000 shows signs of cylinder wear—loss of compression, reduced power output, or increased blow-by—a quality sleeve restores the engine to factory performance specifications. The LA Sleeve Cylinder Sleeve is precision-engineered...09311008- SKU:
- 09311008
- Availability:
- Ships Same Business Day
- Weight:
- 1.21 LBS
- PRODUCT NAME:
- SLEEVE
- UNITS:
- EACH
- RIDING STYLE:
- UTV
$117.95 -
LA Sleeve Cylinder Sleeve for KTM 85 SX 2018-2022 FL5796
LA SLEEVE
$117.95A worn cylinder sleeve compromises compression, power delivery, and engine longevity—especially critical in high-revving two-stroke applications like the KTM 85 SX. The LA Sleeve restores factory bore dimensions and surface finish, allowing you to...09311010- SKU:
- 09311010
- Availability:
- Ships Same Business Day
- Weight:
- 0.51 LBS
- PRODUCT NAME:
- CYLINDER SLEEVE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$117.95 -
KIBBLEWHITE Spring Kit 30-31600
KIBBLEWHITE
$207.83Valve spring performance is foundational to engine reliability and RPM capability—inadequate springs lead to valve float, bent pushrods, and catastrophic failure. The KIBBLEWHITE Spring Kit 30-31600 delivers the consistent preload and lift...09262345- SKU:
- 09262345
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- APPLICATION:
- INTAKE
- RIDING STYLE:
- OFF-ROAD
- SPRING LIFT IMPERIAL:
- 0.440'
- SPRING OPEN PRESSURE:
- INTAKE 147 LB, EXHAUST 203 LB
- MATERIAL:
- TITANIUM
- PRODUCT NAME:
- SPRING KIT
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- TYPE:
- VALVE
$207.83Qty in Cart: 0Quantity:Price:$207.83Subtotal: -
KIBBLEWHITE Intake Valve 40-40652
KIBBLEWHITE
$31.01Intake valve performance directly impacts combustion efficiency, throttle response, and overall engine reliability—especially under high-RPM conditions. The KIBBLEWHITE Black Diamond™ 40-40652 delivers measurable gains in flow characteristics and...09262355- SKU:
- 09262355
- Availability:
- Ships Same Business Day
- Weight:
- 0.09 LBS
- STEM DIAMETER IMPERIAL:
- 0.2155'
- PRODUCT NAME:
- VALVE
- TULIP ANGLE:
- 20°
- HEAD DIAMETER METRIC:
- 35.99 MM
- LENGTH IMPERIAL:
- 3.080'
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- APPLICATION:
- INTAKE
- MATERIAL:
- STAINLESS STEEL
- MODEL:
- BLACK DIAMOND™
$31.01 -
KIBBLEWHITE Exhaust Valve 40-40656
KIBBLEWHITE
$31.01Exhaust valves are mission-critical components that directly impact cylinder sealing, heat management, and engine longevity. The KIBBLEWHITE 40-40656 is engineered to handle extreme combustion temperatures and repeated thermal cycling without...09262357- SKU:
- 09262357
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- UNITS:
- EACH
- PRODUCT NAME:
- VALVE
- TULIP ANGLE:
- 20°
- HEAD DIAMETER METRIC:
- 31.01 MM
- LENGTH IMPERIAL:
- 3.030'
- MODEL:
- BLACK DIAMOND™
- STEM DIAMETER IMPERIAL:
- 0.2150'
$31.01 -
KIBBLEWHITE Spring Kit 40-40660
KIBBLEWHITE
$220.26A quality valve spring kit is fundamental to any high-performance engine build—it's what keeps your valvetrain stable under extreme RPMs and boost conditions. The KIBBLEWHITE Spring Kit 40-40660 delivers the reliability you need for forced induction,...09262359- SKU:
- 09262359
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- APPLICATION:
- INTAKE
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- SPRING LIFT IMPERIAL:
- 0.415'
- SPRING OPEN PRESSURE:
- INTAKE 169 LB, EXHAUST 170 LB
- TYPE:
- VALVE
- MATERIAL:
- TITANIUM
- PRODUCT NAME:
- SPRING KIT
- UNITS:
- KIT
$220.26 -
KIBBLEWHITE Valve Guide 40-40670
KIBBLEWHITE
$17.83Valve guide wear directly impacts compression, oil consumption, and overall engine reliability—making a quality replacement essential for any rebuild or high-mileage refresh. The KIBBLEWHITE 40-40670 uses Ampco-45 bronze, engineered specifically to...09262360- SKU:
- 09262360
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- RIDING STYLE:
- OFF-ROAD
- INSIDE DIAMETER IMPERIAL:
- 0.2150'
- MATERIAL:
- NICKEL
- SIZE IMPERIAL:
- STANDARD
- MATERIAL:
- AMPCO-45
- OUTSIDE DIAMETER IMPERIAL:
- 0.4365'
- PRODUCT NAME:
- VALVE GUIDE
- UNITS:
- EACH
- APPLICATION:
- EXHAUST
- MATERIAL:
- BRONZE
$17.83 -
KIBBLEWHITE Intake Valve 40-40920
KIBBLEWHITE
$31.01Intake valve performance directly impacts combustion efficiency, cylinder head durability, and overall engine longevity. The Kibblewhite Black Diamond™ 40-40920 delivers measurable gains in flow characteristics and wear resistance through precision...09262372- SKU:
- 09262372
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- STEM DIAMETER IMPERIAL:
- 0.1960'
- LENGTH IMPERIAL:
- 3.610'
- MATERIAL:
- STAINLESS STEEL
- UNITS:
- EACH
- PRODUCT NAME:
- VALVE
- RIDING STYLE:
- UTV
- APPLICATION:
- INTAKE
- HEAD DIAMETER METRIC:
- 30.00 MM
- MODEL:
- BLACK DIAMOND™
- RIDING STYLE:
- ATV
- TULIP ANGLE:
- 10°
$31.01 -
KIBBLEWHITE Exhaust Valve 40-40925
KIBBLEWHITE
$31.01Exhaust valves are critical to engine reliability and performance—they endure extreme heat, pressure, and chemical exposure cycle after cycle. The KIBBLEWHITE Black Diamond™ valve delivers the durability and precision you need to maintain consistent...09262375- SKU:
- 09262375
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- LENGTH IMPERIAL:
- 3.655'
- APPLICATION:
- EXHAUST
- MATERIAL:
- STAINLESS STEEL
- UNITS:
- EACH
- MODEL:
- BLACK DIAMOND™
- RIDING STYLE:
- ATV
- STEM DIAMETER IMPERIAL:
- 0.1955'
- TULIP ANGLE:
- 10°
- HEAD DIAMETER METRIC:
- 27.00 MM
- PRODUCT NAME:
- VALVE
- RIDING STYLE:
- UTV
$31.01
