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Dirt Bike Engine

Dirt Bike Engine

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 2003-2014 KTM 200 EXC Sleeve and Piston Kit LAS-5554K

    LA Sleeve 2003-2014 KTM 200 EXC Sleeve and Piston Kit LAS-5554K

    LA SLEEVE

    $422.95
    Revitalize 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
    Qty in Cart: 0
    Quantity:
    Price:
    $422.95
    Subtotal:
  • LA Sleeve Cylinder Sleeve 90mm Bore Honda TRX450FE 1998-2004 H5365

    LA Sleeve Cylinder Sleeve 90mm Bore Honda TRX450FE 1998-2004 H5365

    LA SLEEVE

    $117.95
    If 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
    Qty in Cart: 0
    Quantity:
    Price:
    $117.95
    Subtotal:
  • LA Sleeve Sleeve and Piston Kit Honda TRX450ES 1998-2004 LAS-5365K

    LA Sleeve Sleeve and Piston Kit Honda TRX450ES 1998-2004 LAS-5365K

    LA SLEEVE

    $328.95
    When 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
    Qty in Cart: 0
    Quantity:
    Price:
    $328.95
    Subtotal:
  • LA Sleeve Cylinder Sleeve Honda TRX500FE 2005-2009 H5591

    LA Sleeve Cylinder Sleeve Honda TRX500FE 2005-2009 H5591

    LA SLEEVE

    $117.95
    Worn 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
    Qty in Cart: 0
    Quantity:
    Price:
    $117.95
    Subtotal:
  • LA Sleeve Cylinder Sleeve for Polaris General 1000 2016-2017 FL5777 LA Sleeve Cylinder Sleeve for Polaris General 1000 2016-2017 FL5777

    LA Sleeve Cylinder Sleeve for Polaris General 1000 2016-2017 FL5777

    LA SLEEVE

    $117.95
    When 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
    Qty in Cart: 0
    Quantity:
    Price:
    $117.95
    Subtotal:
  • LA Sleeve Cylinder Sleeve for KTM 85 SX 2018-2022 FL5796

    LA Sleeve Cylinder Sleeve for KTM 85 SX 2018-2022 FL5796

    LA SLEEVE

    $117.95
    A 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
    Qty in Cart: 0
    Quantity:
    Price:
    $117.95
    Subtotal:
  • KIBBLEWHITE Spring Kit 30-31600

    KIBBLEWHITE Spring Kit 30-31600

    KIBBLEWHITE

    $207.83
    Valve 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
    Qty in Cart: 0
    Quantity:
    Price:
    $207.83
    Subtotal:
  • KIBBLEWHITE Intake Valve 40-40652

    KIBBLEWHITE Intake Valve 40-40652

    KIBBLEWHITE

    $31.01
    Intake 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
    Qty in Cart: 0
    Quantity:
    Price:
    $31.01
    Subtotal:
  • KIBBLEWHITE Exhaust Valve 40-40656

    KIBBLEWHITE Exhaust Valve 40-40656

    KIBBLEWHITE

    $31.01
    Exhaust 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
    Qty in Cart: 0
    Quantity:
    Price:
    $31.01
    Subtotal:
  • KIBBLEWHITE Spring Kit 40-40660

    KIBBLEWHITE Spring Kit 40-40660

    KIBBLEWHITE

    $220.26
    A 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
    Qty in Cart: 0
    Quantity:
    Price:
    $220.26
    Subtotal:
  • KIBBLEWHITE Valve Guide 40-40670

    KIBBLEWHITE Valve Guide 40-40670

    KIBBLEWHITE

    $17.83
    Valve 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
    Qty in Cart: 0
    Quantity:
    Price:
    $17.83
    Subtotal:
  • KIBBLEWHITE Intake Valve 40-40920

    KIBBLEWHITE Intake Valve 40-40920

    KIBBLEWHITE

    $31.01
    Intake 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
    Qty in Cart: 0
    Quantity:
    Price:
    $31.01
    Subtotal:
  • KIBBLEWHITE Exhaust Valve 40-40925

    KIBBLEWHITE Exhaust Valve 40-40925

    KIBBLEWHITE

    $31.01
    Exhaust 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
    Qty in Cart: 0
    Quantity:
    Price:
    $31.01
    Subtotal:
  • KIBBLEWHITE Valve Guide 60-60730

    KIBBLEWHITE Valve Guide 60-60730

    KIBBLEWHITE

    $15.92
    Valve guides are critical to engine longevity, and Kibblewhite's 60-60730 delivers the thermal management and wear resistance your high-performance build demands. Manufactured from Ampco-45—an 80% copper, 5% nickel compound—these guides dissipate heat...
    09262381
    SKU:
    09262381
    Availability:
    Ships Same Business Day
    Weight:
    0.02 LBS
    MATERIAL:
    BRONZE
    OUTSIDE DIAMETER IMPERIAL:
    0.4170'
    PRODUCT NAME:
    VALVE GUIDE
    APPLICATION:
    EXHAUST
    MATERIAL:
    AMPCO-45
    MATERIAL:
    NICKEL
    SIZE IMPERIAL:
    STANDARD
    INSIDE DIAMETER IMPERIAL:
    0.2155'
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    $15.92
    Qty in Cart: 0
    Quantity:
    Price:
    $15.92
    Subtotal:
  • KIBBLEWHITE Valve Seal - 6mm 71017-4

    KIBBLEWHITE Valve Seal - 6mm 71017-4

    KIBBLEWHITE

    $13.96
    Valve seal integrity is critical to engine longevity and oil consumption control—compromised seals lead to blow-by, performance loss, and costly engine damage. KIBBLEWHITE's solid Viton® construction delivers the durability and precision fit your engine...
    09262383
    SKU:
    09262383
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    STEM DIAMETER METRIC:
    6.00 MM
    APPLICATION:
    EXHAUST
    OUTSIDE DIAMETER IMPERIAL:
    0.4750'
    PRODUCT NAME:
    SEAL
    TYPE:
    VALVE
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    ATV
    MATERIAL:
    VITON
    UNITS:
    4 PACK
    $13.96
    Qty in Cart: 0
    Quantity:
    Price:
    $13.96
    Subtotal:
  • KIBBLEWHITE Exhaust Valve Guide 82-82380

    KIBBLEWHITE Exhaust Valve Guide 82-82380

    KIBBLEWHITE

    $18.54
    Valve guide wear is one of the most common causes of oil consumption and compression loss in high-mileage engines. The KIBBLEWHITE Exhaust Valve Guide 82-82380 replaces worn guides with a precision-engineered component designed to restore proper valve...
    09262397
    SKU:
    09262397
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    APPLICATION:
    EXHAUST
    MATERIAL:
    AMPCO-45
    PRODUCT NAME:
    VALVE GUIDE
    RIDING STYLE:
    ATV
    SIZE IMPERIAL:
    STANDARD
    INSIDE DIAMETER IMPERIAL:
    0.2155'
    OUTSIDE DIAMETER IMPERIAL:
    0.4353'
    UNITS:
    EACH
    $18.54
    Qty in Cart: 0
    Quantity:
    Price:
    $18.54
    Subtotal:
  • KIBBLEWHITE Intake Valve 82-82312

    KIBBLEWHITE Intake Valve 82-82312

    KIBBLEWHITE

    $37.55
    Intake valve performance directly impacts your engine's breathing efficiency and power delivery. The KIBBLEWHITE Black Diamond™ valve eliminates friction losses and resists the thermal cycling and corrosion that degrade stock valves over time. Whether...
    09262400
    SKU:
    09262400
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    TULIP ANGLE:
    25°
    MATERIAL:
    STAINLESS STEEL
    STEM DIAMETER IMPERIAL:
    0.2357'
    UNITS:
    EACH
    APPLICATION:
    INTAKE
    HEAD DIAMETER METRIC:
    35.00 MM
    LENGTH IMPERIAL:
    4.510'
    MODEL:
    BLACK DIAMOND™
    RIDING STYLE:
    ATV
    PRODUCT NAME:
    VALVE
    $37.55
    Qty in Cart: 0
    Quantity:
    Price:
    $37.55
    Subtotal:
  • KIBBLEWHITE Valve Guide 40-40570

    KIBBLEWHITE Valve Guide 40-40570

    KIBBLEWHITE

    $17.83
    Valve guide wear directly impacts compression, oil consumption, and combustion efficiency—and Kibblewhite's engineered solution addresses all three. The Ampco-45 compound used in this guide delivers superior heat conductivity and wear resistance, keeping...
    09262660
    SKU:
    09262660
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    APPLICATION:
    INTAKE
    RIDING STYLE:
    ATV
    MATERIAL:
    C630 BRONZE
    SIZE IMPERIAL:
    STANDARD
    APPLICATION:
    EXHAUST
    INSIDE DIAMETER IMPERIAL:
    0.2150'
    OUTSIDE DIAMETER IMPERIAL:
    0.4365'
    PRODUCT NAME:
    VALVE GUIDE
    UNITS:
    EACH
    Qty in Cart: 0
    Quantity:
    Price:
    $17.83
    Subtotal:
  • KIBBLEWHITE Intake Valve Kit 60-60470

    KIBBLEWHITE Intake Valve Kit 60-60470

    KIBBLEWHITE

    $185.23
    If you're running high-RPM applications or pushing your engine beyond stock parameters, valve wear becomes a critical limiting factor in reliability and longevity. The KIBBLEWHITE Intake Valve Kit 60-60470 replaces OEM titanium components with superior...
    09262663
    SKU:
    09262663
    Availability:
    Ships Same Business Day
    Weight:
    0.40 LBS
    APPLICATION:
    INTAKE
    SPRING LIFT:
    0,445'
    TYPE:
    CONVERSION
    SPRING SEAT PRESSURE:
    51 LB
    PRODUCT NAME:
    VALVE KIT
    RIDING STYLE:
    OFF-ROAD
    SPRING OPEN PRESSURE:
    160 LB
    UNITS:
    KIT
    MATERIAL:
    STAINLESS STEEL
    SPRING LIFT IMPERIAL:
    0.445'
    $185.23
    Qty in Cart: 0
    Quantity:
    Price:
    $185.23
    Subtotal:
  • KIBBLEWHITE Valve Guide 60-60670

    KIBBLEWHITE Valve Guide 60-60670

    KIBBLEWHITE

    $15.92
    Valve guide wear directly impacts cylinder head sealing, oil consumption, and overall engine reliability—especially in high-RPM or forced-induction applications where precision tolerances are critical. The KIBBLEWHITE 60-60670 valve guide uses Ampco-45...
    09262667
    SKU:
    09262667
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    MATERIAL:
    NICKEL
    SIZE IMPERIAL:
    STANDARD
    UNITS:
    EACH
    APPLICATION:
    INTAKE
    INSIDE DIAMETER IMPERIAL:
    0.2155'
    RIDING STYLE:
    OFF-ROAD
    APPLICATION:
    EXHAUST
    MATERIAL:
    BRONZE
    MATERIAL:
    AMPCO-45
    OUTSIDE DIAMETER IMPERIAL:
    0.4170'
    PRODUCT NAME:
    VALVE GUIDE
    Qty in Cart: 0
    Quantity:
    Price:
    $15.92
    Subtotal:
  • Total: items /

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Dirt Bike Engine Parts

Keep your dirt bike running smoothly and prolong the life of its engine with essential general maintenance. But when parts start to break down, don't let it stop you from getting out on the trails! JJ Motorsports has all that you need for minor jobs like oil changes or major overhauls such as a complete rebuild - carrying top aftermarket brands . Get back in gear faster by shopping our full line of high-quality dirt bike engine parts here today at JJ Motorsports!

 

At JJ Motorsports, we want to make sure you don't miss out on the ride! If your motor has blown or radiator smashed, our gearheads can help get you back in the seat. We carry piston kits from top brands like Wiseco and Wrench Rabbit engine kits so that riders have access to a wide range of parts for their dirt bike engine rebuilds. Plus – with gaskets at-the-ready when it comes time for any leakages - no need to worry about maintenance issues either; simply stay up on oil & filter changes and let us take care of everything else. Got queries? Just give one of our knowledgeable staff members a call at 1-231‐767‐5055 where they'll be more than happy provide advice, instructions and tailored answers catered just for YOU!

Big Power, Nice Sound!

Picked up a Pro Circuit pipe and silencer for my YZ125 it’s a game changer. The power feels way better and the sound is awesome.

Tyler D. - 06/12

Perfect Fit

First time ordering here and dang y’all knocked it outta the park! The wheels fit my Ranger UTV perfect, and I’ll definitely be back for more 5 stars all day!

Sarah L. - 08/24

Fast Shipping!!

Ordered on a Monday, and it was on my doorstep by Wednesday! Super impressed with how fast the shipping was.

Jason P. - 09/13

Helps keep cool, works great!

Bought the dual pass Allstar radiator for my build, and it’s been solid. Keeps the engine running cool even on the hottest days no complaints here!

Jake M. - 05/21

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