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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
  • MOOSE RACING Valve Shim - 9.48 x 3.40 - 5 pack MSE5PK948340

    MOOSE RACING Valve Shim - 9.48 x 3.40 - 5 pack MSE5PK948340

    MOOSE RACING

    $9.95
    Valve shim maintenance demands precision and reliability—guesswork has no place in your valve train. These forged 4140 cold rolled steel shims give you the durability and accuracy needed to dial in proper valve clearances without the brittleness or...
    09261972
    SKU:
    09261972
    Availability:
    Ships Same Business Day
    Weight:
    0.02 LBS
    RIDING STYLE:
    OFF-ROAD
    RIDING STYLE:
    UTV
    RIDING STYLE:
    WATERCRAFT
    VALVE SHIM THICKNESS METRIC:
    3.40 MM
    RIDING STYLE:
    ATV
    TYPE:
    VALVE
    MATERIAL:
    ROLLED
    MATERIAL:
    STEEL
    OUTSIDE DIAMETER METRIC:
    9.48 MM
    PRODUCT NAME:
    SHIM
    RIDING STYLE:
    SNOW
    UNITS:
    5 PACK
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    STREET
    $9.95
    Qty in Cart: 0
    Quantity:
    Price:
    $9.95
    Subtotal:
  • MOOSE RACING Valve Seal Kit M30-30550

    MOOSE RACING Valve Seal Kit M30-30550

    MOOSE RACING

    $15.95
    Valve seal degradation is one of the most common causes of oil consumption and compression loss in high-mileage engines—issues that compound quickly under racing conditions or sustained performance driving. The MOOSE RACING M30-30550 Valve Seal Kit...
    09262815
    SKU:
    09262815
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    COLOR/FINISH:
    RED
    MATERIAL:
    VITON
    TYPE:
    VALVE STEM
    APPLICATION:
    INTAKE
    BASE COLOR:
    RED
    PRODUCT NAME:
    SEAL KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    EXHAUST
    $15.95
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Valve Seal Kit M30-30680

    MOOSE RACING Valve Seal Kit M30-30680

    MOOSE RACING

    $15.95
    Valve seal degradation leads to oil consumption, blow-by, and performance loss—especially under sustained high RPM operation. The MOOSE RACING Valve Seal Kit M30-30680 replaces worn OEM seals with precision-engineered components that maintain proper oil...
    09262816
    SKU:
    09262816
    Availability:
    Ships Same Business Day
    Weight:
    0.11 LBS
    COLOR/FINISH:
    RED
    MATERIAL:
    VITON
    PRODUCT NAME:
    SEAL KIT
    TYPE:
    VALVE STEM
    APPLICATION:
    INTAKE
    BASE COLOR:
    RED
    APPLICATION:
    EXHAUST
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $15.95
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Valve Seal Kit M30-31530

    MOOSE RACING Valve Seal Kit M30-31530

    MOOSE RACING

    $15.95
    Valve seal degradation is one of the most common culprits behind oil consumption, reduced compression, and failed inspections—especially under high-boost or sustained high-RPM conditions. The MOOSE RACING Valve Seal Kit M30-31530 replaces compromised OEM...
    09262818
    SKU:
    09262818
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    APPLICATION:
    EXHAUST
    BASE COLOR:
    RED
    COLOR/FINISH:
    RED
    PRODUCT NAME:
    SEAL KIT
    TYPE:
    VALVE STEM
    MATERIAL:
    VITON
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    $15.95
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Valve Seal Kit M60-60570

    MOOSE RACING Valve Seal Kit M60-60570

    MOOSE RACING

    $15.95
    Valve seal degradation is one of the most common causes of compression loss and oil consumption in high-mileage engines. The MOOSE RACING Valve Seal Kit M60-60570 replaces worn OEM seals with precision-manufactured components engineered to maintain...
    09262827
    SKU:
    09262827
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    EXHAUST
    APPLICATION:
    INTAKE
    COLOR/FINISH:
    RED
    PRODUCT NAME:
    SEAL KIT
    BASE COLOR:
    RED
    MATERIAL:
    VITON
    TYPE:
    VALVE STEM
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Valve Seal Kit M60-60870

    MOOSE RACING Valve Seal Kit M60-60870

    MOOSE RACING

    $15.95
    Valve seals are critical to engine longevity—they prevent oil from leaking into the combustion chamber and maintain compression integrity. Over time, OEM seals degrade under heat and pressure, leading to oil consumption, blue smoke, and reduced...
    09262829
    SKU:
    09262829
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    APPLICATION:
    INTAKE
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    VITON
    COLOR/FINISH:
    RED
    PRODUCT NAME:
    SEAL KIT
    APPLICATION:
    EXHAUST
    BASE COLOR:
    RED
    TYPE:
    VALVE STEM
    $15.95
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Valve Seal Kit M80-80880

    MOOSE RACING Valve Seal Kit M80-80880

    MOOSE RACING

    $15.95
    Valve seal degradation causes oil blow-by, compression loss, and increased emissions—problems that compound quickly under racing conditions or high-mileage use. The MOOSE RACING M80-80880 Valve Seal Kit delivers OEM-equivalent fitment with improved...
    09262832
    SKU:
    09262832
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    APPLICATION:
    INTAKE
    BASE COLOR:
    RED
    RIDING STYLE:
    ATV
    RIDING STYLE:
    OFF-ROAD
    COLOR/FINISH:
    RED
    MATERIAL:
    VITON
    PRODUCT NAME:
    SEAL KIT
    UNITS:
    KIT
    APPLICATION:
    EXHAUST
    TYPE:
    VALVE STEM
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Valve and Spring Kit M30-31860

    MOOSE RACING Valve and Spring Kit M30-31860

    MOOSE RACING

    $217.95
    If you're running high-mileage racing applications, OEM valve and spring components become a reliability liability. The MOOSE RACING M30-31860 addresses this with Black Diamond stainless steel intake valves engineered to deliver up to 4x longer service...
    09262435
    SKU:
    09262435
    Availability:
    Ships Same Business Day
    Weight:
    0.25 LBS
    APPLICATION:
    EXHAUST
    APPLICATION:
    INTAKE
    MATERIAL:
    STAINLESS STEEL
    PRODUCT NAME:
    VALVE AND SPRING KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $217.95
    Qty in Cart: 0
    Quantity:
    Price:
    $217.95
    Subtotal:
  • MOOSE RACING Valve and Spring Kit M30-31960

    MOOSE RACING Valve and Spring Kit M30-31960

    MOOSE RACING

    $196.95
    If you're running high-mileage on OEM titanium valves, you're leaving performance and reliability on the table. The MOOSE RACING Valve and Spring Kit M30-31960 replaces worn intake components with stainless steel Black Diamond valves engineered to...
    09262436
    SKU:
    09262436
    Availability:
    Ships Same Business Day
    Weight:
    0.46 LBS
    APPLICATION:
    EXHAUST
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE AND SPRING KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    STAINLESS STEEL
    $196.95
    Qty in Cart: 0
    Quantity:
    Price:
    $196.95
    Subtotal:
  • MOOSE RACING Intake Valve Kit M40-40350

    MOOSE RACING Intake Valve Kit M40-40350

    MOOSE RACING

    $196.95
    Stock intake valves are a limiting factor in any high-performance engine build, prone to premature wear and thermal fatigue under sustained boost or high RPM loads. The MOOSE RACING M40-40350 Intake Valve Kit replaces OEM titanium components with...
    09262439
    SKU:
    09262439
    Availability:
    Ships Same Business Day
    Weight:
    0.40 LBS
    MATERIAL:
    STAINLESS STEEL
    PRODUCT NAME:
    VALVE KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    $196.95
    Qty in Cart: 0
    Quantity:
    Price:
    $196.95
    Subtotal:
  • MOOSE RACING Valve and Spring Kit M80-80860

    MOOSE RACING Valve and Spring Kit M80-80860

    MOOSE RACING

    $217.95
    Factory valve trains wear out—MOOSE Racing's stainless steel conversion kit extends intake valve life by up to 4x over OEM titanium components while improving flow and performance. If you're serious about maximizing engine longevity and reliability in...
    09262458
    SKU:
    09262458
    Availability:
    Ships Same Business Day
    Weight:
    0.30 LBS
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE AND SPRING KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    EXHAUST
    MATERIAL:
    STAINLESS STEEL
    $217.95
    Qty in Cart: 0
    Quantity:
    Price:
    $217.95
    Subtotal:
  • MOOSE RACING Intake Valve Kit M80-81050

    MOOSE RACING Intake Valve Kit M80-81050

    MOOSE RACING

    $196.95
    If you're running a high-performance engine, your intake valves are working harder than factory components were designed to handle. The MOOSE RACING Intake Valve Kit M80-81050 replaces OEM titanium valves with proprietary Black Diamond stainless steel...
    09262461
    SKU:
    09262461
    Availability:
    Ships Same Business Day
    Weight:
    0.55 LBS
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    STAINLESS STEEL
    Qty in Cart: 0
    Quantity:
    Price:
    $196.95
    Subtotal:
  • MOOSE RACING Valve and Spring Kit M80-81060

    MOOSE RACING Valve and Spring Kit M80-81060

    MOOSE RACING

    $196.95
    OEM titanium intake valves wear out fast under high-performance demands, limiting your engine's lifespan and reliability. The MOOSE RACING Valve and Spring Kit M80-81060 replaces them with stainless steel Black Diamond valves that last up to 4x longer...
    09262462
    SKU:
    09262462
    Availability:
    Ships Same Business Day
    Weight:
    0.45 LBS
    APPLICATION:
    EXHAUST
    MATERIAL:
    STAINLESS STEEL
    PRODUCT NAME:
    VALVE AND SPRING KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    $196.95
    Qty in Cart: 0
    Quantity:
    Price:
    $196.95
    Subtotal:
  • MOOSE RACING Intake Valve Kit M96-96070

    MOOSE RACING Intake Valve Kit M96-96070

    MOOSE RACING

    $196.95
    If you're running hard on the track or pushing your engine to its limits, your intake valves are working overtime. The MOOSE RACING Intake Valve Kit M96-96070 replaces your stock titanium valves with premium stainless steel Black Diamond valves that...
    09262463
    SKU:
    09262463
    Availability:
    Ships Same Business Day
    Weight:
    0.65 LBS
    MATERIAL:
    STAINLESS STEEL
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $196.95
    Qty in Cart: 0
    Quantity:
    Price:
    $196.95
    Subtotal:
  • MOOSE RACING Valve and Spring Kit M96-96360

    MOOSE RACING Valve and Spring Kit M96-96360

    MOOSE RACING

    $196.95
    If you're running a high-performance engine, your valve train is under constant stress—and OEM titanium valves often become the limiting factor in reliability and longevity. The MOOSE RACING Valve and Spring Kit M96-96360 replaces those components with...
    09262464
    SKU:
    09262464
    Availability:
    Ships Same Business Day
    Weight:
    0.55 LBS
    APPLICATION:
    EXHAUST
    MATERIAL:
    STAINLESS STEEL
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE AND SPRING KIT
    RIDING STYLE:
    OFF-ROAD
    $196.95
    Qty in Cart: 0
    Quantity:
    Price:
    $196.95
    Subtotal:
  • MOOSE RACING Valve and Spring Kit M96-96460

    MOOSE RACING Valve and Spring Kit M96-96460

    MOOSE RACING

    $217.95
    If you're running high-mileage or high-performance applications, OEM titanium intake valves will eventually become a reliability bottleneck. The MOOSE RACING Valve and Spring Kit M96-96460 replaces them with stainless steel Black Diamond valves...
    09262468
    SKU:
    09262468
    Availability:
    Ships Same Business Day
    Weight:
    0.45 LBS
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE AND SPRING KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    EXHAUST
    MATERIAL:
    STAINLESS STEEL
    $217.95
    Qty in Cart: 0
    Quantity:
    Price:
    $217.95
    Subtotal:
  • MOOSE RACING Cylinder - Standard - KTM MSE50003

    MOOSE RACING Cylinder - Standard - KTM MSE50003

    MOOSE RACING

    $474.95
    A worn or damaged cylinder directly compromises compression, power delivery, and engine longevity. The MOOSE RACING Cylinder restores your engine to factory specifications with precision manufacturing and a durable nickel silicon carbide-plated bore that...
    09310627
    SKU:
    09310627
    Availability:
    Ships Same Business Day
    Weight:
    2.20 LBS
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    MATERIAL:
    CAST
    MATERIAL:
    ALUMINUM
    CYLINDER BORE COATING:
    NICKEL-SILICON CARBIDE
    PRODUCT NAME:
    CYLINDER
    $474.95
    Qty in Cart: 0
    Quantity:
    Price:
    $474.95
    Subtotal:
  • MOOSE RACING Cylinder - Standard - YZ250F MSE20010

    MOOSE RACING Cylinder - Standard - YZ250F MSE20010

    MOOSE RACING

    $402.95
    A worn or damaged cylinder directly impacts engine compression, throttle response, and overall reliability on the track or trail. The MOOSE RACING Cylinder restores OEM performance specifications with a durable, low-friction bore that dissipates heat...
    09310629
    SKU:
    09310629
    Availability:
    Ships Same Business Day
    Weight:
    2.26 LBS
    RIDING STYLE:
    OFF-ROAD
    ENGINE TYPE:
    4-CYCLE
    MATERIAL:
    CAST
    PRODUCT NAME:
    CYLINDER
    CYLINDER BORE COATING:
    NICKEL-SILICON CARBIDE
    MATERIAL:
    ALUMINUM
    UNITS:
    EACH
    $402.95
    Qty in Cart: 0
    Quantity:
    Price:
    $402.95
    Subtotal:
  • MOOSE RACING Cylinder - Standard MSE10002

    MOOSE RACING Cylinder - Standard MSE10002

    MOOSE RACING

    $372.95
    A worn or damaged cylinder compromises compression, increases blow-by, and forces your engine to work harder while delivering less power. The MOOSE RACING MSE10002 restores your engine to factory performance specifications with precision engineering and...
    09310442
    SKU:
    09310442
    Availability:
    Ships Same Business Day
    Weight:
    3.51 LBS
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    MATERIAL:
    CAST
    MATERIAL:
    ALUMINUM
    CYLINDER BORE COATING:
    NICKEL-SILICON CARBIDE
    PRODUCT NAME:
    CYLINDER
    $372.95
    Qty in Cart: 0
    Quantity:
    Price:
    $372.95
    Subtotal:
  • MOOSE RACING Cylinder - Standard MSE10007

    MOOSE RACING Cylinder - Standard MSE10007

    MOOSE RACING

    $377.95
    A worn or damaged cylinder directly compromises your engine's compression, power delivery, and reliability—especially in high-performance applications. The MOOSE RACING MSE10007 cylinder restores OEM-spec bore geometry with a durable nickel silicon...
    09310447
    SKU:
    09310447
    Availability:
    Ships Same Business Day
    Weight:
    2.66 LBS
    MATERIAL:
    CAST
    PRODUCT NAME:
    CYLINDER
    CYLINDER BORE COATING:
    NICKEL-SILICON CARBIDE
    RIDING STYLE:
    OFF-ROAD
    MATERIAL:
    ALUMINUM
    UNITS:
    EACH
    $377.95
    Qty in Cart: 0
    Quantity:
    Price:
    $377.95
    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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