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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
  • WSM Piston Rings 010-925

    WSM Piston Rings 010-925

    WSM

    $24.97
    Piston rings are critical to engine performance—they seal combustion pressure, manage oil consumption, and directly impact power output and longevity. WSM Piston Rings 010-925 deliver consistent...
    010925
    SKU:
    010925
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    BORE - OVERSIZE:
    STANDARD
    BORE - OVERSIZE METRIC:
    STANDARD
    PRODUCT NAME:
    PISTON RING
    RIDING STYLE:
    WATERCRAFT
    PISTON MATERIAL:
    ALUMINUM
    UNITS:
    SET
    $24.97
    Qty in Cart: 0
    Quantity:
    Price:
    $24.97
    Subtotal:
  • WSM Piston Rings 010-925-05

    WSM Piston Rings 010-925-05

    WSM

    $24.97
    Piston rings are critical to engine performance—they create the seal between pistons and cylinder walls that maintains compression, controls oil consumption, and prevents blowby. WSM Piston Rings...
    01092505
    SKU:
    01092505
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    RIDING STYLE:
    WATERCRAFT
    PISTON MATERIAL:
    ALUMINUM
    BORE - OVERSIZE:
    +0,50 MM
    BORE - OVERSIZE METRIC:
    +0.50 MM
    PRODUCT NAME:
    PISTON RING
    UNITS:
    SET
    $24.97
    Qty in Cart: 0
    Quantity:
    Price:
    $24.97
    Subtotal:
  • WSM Piston Rings 010-925-06

    WSM Piston Rings 010-925-06

    WSM

    $24.97
    Piston rings are critical wear items that directly impact compression, blow-by control, and oil consumption—neglecting them leads to power loss and engine damage. WSM Piston Rings 010-925-06 deliver...
    01092506
    SKU:
    01092506
    Availability:
    Ships Same Business Day
    Weight:
    0.03 LBS
    UNITS:
    SET
    BORE - OVERSIZE:
    +0,75 MM
    PISTON MATERIAL:
    ALUMINUM
    PRODUCT NAME:
    PISTON RING
    RIDING STYLE:
    WATERCRAFT
    BORE - OVERSIZE METRIC:
    +0.75 MM
    $24.97
    Qty in Cart: 0
    Quantity:
    Price:
    $24.97
    Subtotal:
  • WSM Piston Rings 010-930

    WSM Piston Rings 010-930

    WSM

    $28.34
    Piston rings are critical to engine sealing and compression—worn or substandard rings lead to blowby, oil consumption, and power loss. WSM Piston Rings 010-930 deliver precise tolerances and reliable...
    010930
    SKU:
    010930
    Availability:
    Ships Same Business Day
    Weight:
    0.04 LBS
    PISTON MATERIAL:
    ALUMINUM
    PRODUCT NAME:
    PISTON RING
    UNITS:
    SET
    BORE - OVERSIZE:
    STANDARD
    BORE - OVERSIZE METRIC:
    STANDARD
    RIDING STYLE:
    WATERCRAFT
    $28.34
    Qty in Cart: 0
    Quantity:
    Price:
    $28.34
    Subtotal:
  • MOOSE RACING Inner Clutch Cover Gasket 816672

    MOOSE RACING Inner Clutch Cover Gasket 816672

    MOOSE RACING

    $16.90
    A leaking clutch cover gasket compromises engine sealing and invites oil contamination into your clutch assembly—exactly what your precision machinery doesn't need. This OEM-equivalent gasket from...
    09346160
    SKU:
    09346160
    Availability:
    Ships Same Business Day
    Weight:
    0.11 LBS
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    CLUTCH COVER
    UNITS:
    EACH
    PRODUCT NAME:
    GASKET
    $16.90
    Qty in Cart: 0
    Quantity:
    Price:
    $16.90
    Subtotal:
  • MOOSE RACING Motor Seals - YZ250 822304

    MOOSE RACING Motor Seals - YZ250 822304

    MOOSE RACING

    $33.45
    A complete engine seal failure can sideline your YZ250 indefinitely—and OEM replacement kits come with premium pricing that cuts into your race budget. MOOSE Racing Motor Seals deliver genuine...
    09350113
    SKU:
    09350113
    Availability:
    Ships Same Business Day
    Weight:
    0.21 LBS
    APPLICATION:
    ENGINE
    PRODUCT NAME:
    SEAL
    UNITS:
    SET
    TYPE:
    OIL
    RIDING STYLE:
    OFF-ROAD
    $33.45
    Qty in Cart: 0
    Quantity:
    Price:
    $33.45
    Subtotal:
  • MOOSE RACING Exhaust Gasket Kit 823002

    MOOSE RACING Exhaust Gasket Kit 823002

    MOOSE RACING

    $9.68
    A leaking exhaust system ruins performance and wastes horsepower before it ever leaves your engine. OEM gaskets deteriorate under heat cycles, causing exhaust leaks that compromise seal integrity and...
    09345272
    SKU:
    09345272
    Availability:
    Ships Same Business Day
    Weight:
    0.16 LBS
    PRODUCT NAME:
    GASKET KIT
    TYPE:
    EXHAUST
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $9.68
    Qty in Cart: 0
    Quantity:
    Price:
    $9.68
    Subtotal:
  • MOOSE RACING Exhaust Gasket Kit 823176

    MOOSE RACING Exhaust Gasket Kit 823176

    MOOSE RACING

    $21.48
    A quality exhaust gasket kit is essential for maintaining a proper seal between exhaust manifold and header joints, preventing costly exhaust leaks that compromise performance and increase emissions...
    09345351
    SKU:
    09345351
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    PRODUCT NAME:
    GASKET KIT
    TYPE:
    EXHAUST
    UNITS:
    KIT
    RIDING STYLE:
    OFF-ROAD
    $21.48
    Qty in Cart: 0
    Quantity:
    Price:
    $21.48
    Subtotal:
  • MOOSE RACING Exhaust Gasket Kit 823187

    MOOSE RACING Exhaust Gasket Kit 823187

    MOOSE RACING

    $34.85
    Exhaust gasket degradation is one of the most common sources of power loss and unwanted emissions in high-performance engines. A failed or deteriorating gasket compromises seal integrity, allowing...
    09345352
    SKU:
    09345352
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    PRODUCT NAME:
    GASKET KIT
    TYPE:
    EXHAUST
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $34.85
    Qty in Cart: 0
    Quantity:
    Price:
    $34.85
    Subtotal:
  • MOOSE RACING Complete Gasket Kit 808374

    MOOSE RACING Complete Gasket Kit 808374

    MOOSE RACING

    $125.59
    A complete engine and transmission rebuild demands precision-fit gaskets and seals that won't fail under sustained load. The MOOSE RACING Complete Gasket Kit 808374 delivers OEM-equivalent...
    09345357
    SKU:
    09345357
    Availability:
    Ships Same Business Day
    Weight:
    0.35 LBS
    TYPE:
    ENGINE
    ENGINE TYPE:
    4-STROKE
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    PRODUCT NAME:
    GASKET
    RIDING STYLE:
    STREET
    UNITS:
    KIT
    $125.59
    Qty in Cart: 0
    Quantity:
    Price:
    $125.59
    Subtotal:
  • MOOSE RACING Complete Motor Gasket Kit - KX450F 808485

    MOOSE RACING Complete Motor Gasket Kit - KX450F 808485

    MOOSE RACING

    $175.37
    A complete engine and transmission rebuild demands precision-fitted gaskets and seals that won't compromise your work or your engine's longevity. The MOOSE RACING Complete Motor Gasket Kit delivers...
    09345358
    SKU:
    09345358
    Availability:
    Ships Same Business Day
    Weight:
    0.30 LBS
    TYPE:
    ENGINE
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    UNITS:
    KIT
    PRODUCT NAME:
    GASKET
    $175.37
    Qty in Cart: 0
    Quantity:
    Price:
    $175.37
    Subtotal:
  • MOOSE RACING Valve Seal Kit M30-31540

    MOOSE RACING Valve Seal Kit M30-31540

    MOOSE RACING

    $15.95
    Valve seal degradation is a common cause of oil consumption and compression loss, particularly in high-performance and turbocharged applications where thermal stress accelerates wear. The MOOSE...
    09262819
    SKU:
    09262819
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    SEAL KIT
    TYPE:
    VALVE STEM
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    COLOR/FINISH:
    RED
    BASE COLOR:
    RED
    MATERIAL:
    VITON
    RIDING STYLE:
    OFF-ROAD
    $15.95
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Valve Seal Kit M40-40160

    MOOSE RACING Valve Seal Kit M40-40160

    MOOSE RACING

    $15.95
    Factory valve seals degrade under sustained high heat and aggressive driving, leading to oil consumption, blow-by, and reduced ring seal integrity. The MOOSE RACING M40-40160 Valve Seal Kit replaces...
    09262822
    SKU:
    09262822
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    MATERIAL:
    VITON
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    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 M40-40790

    MOOSE RACING Valve Seal Kit M40-40790

    MOOSE RACING

    $15.95
    Valve seal degradation is a silent killer of engine performance and longevity—worn seals allow oil to seep into combustion chambers, causing blow-by, reduced compression, and accelerated wear on...
    09262824
    SKU:
    09262824
    Availability:
    Ships Same Business Day
    Weight:
    0.11 LBS
    APPLICATION:
    INTAKE
    BASE COLOR:
    RED
    COLOR/FINISH:
    RED
    MATERIAL:
    VITON
    TYPE:
    VALVE STEM
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    SEAL KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $15.95
    Qty in Cart: 0
    Quantity:
    Price:
    $15.95
    Subtotal:
  • MOOSE RACING Cylinder - Standard MSE10006

    MOOSE RACING Cylinder - Standard MSE10006

    MOOSE RACING

    $402.95
    A worn or damaged cylinder directly impacts compression, heat management, and overall engine reliability—making replacement essential for consistent performance on the track or trail. The MOOSE...
    09310446
    SKU:
    09310446
    Availability:
    Ships Same Business Day
    Weight:
    3.23 LBS
    MATERIAL:
    CAST
    PRODUCT NAME:
    CYLINDER
    MATERIAL:
    ALUMINUM
    UNITS:
    EACH
    CYLINDER BORE COATING:
    NICKEL-SILICON CARBIDE
    RIDING STYLE:
    OFF-ROAD
    $402.95
    Qty in Cart: 0
    Quantity:
    Price:
    $402.95
    Subtotal:
  • MOOSE RACING Cylinder - Standard MSE20001

    MOOSE RACING Cylinder - Standard MSE20001

    MOOSE RACING

    $380.95
    A worn or damaged cylinder compromises compression, power delivery, and engine reliability—especially under racing conditions where tolerances matter. The MOOSE RACING Cylinder MSE20001 restores OEM...
    09310450
    SKU:
    09310450
    Availability:
    Ships Same Business Day
    Weight:
    3.44 LBS
    MATERIAL:
    CAST
    PRODUCT NAME:
    CYLINDER
    RIDING STYLE:
    ATV
    RIDING STYLE:
    OFF-ROAD
    CYLINDER BORE COATING:
    NICKEL-SILICON CARBIDE
    MATERIAL:
    ALUMINUM
    UNITS:
    EACH
    $380.95
    Qty in Cart: 0
    Quantity:
    Price:
    $380.95
    Subtotal:
  • MOOSE RACING Piston Ring - For 57.95 mm Piston MSE55910005800

    MOOSE RACING Piston Ring - For 57.95 mm Piston MSE55910005800

    MOOSE RACING

    $38.80
    A worn or damaged piston ring compromises combustion efficiency, increases blow-by, and forces your engine to work harder while losing power. MOOSE Racing piston rings are precision-engineered...
    09120845
    SKU:
    09120845
    Availability:
    Ships Same Business Day
    Weight:
    1.01 LBS
    UNITS:
    EACH
    PRODUCT NAME:
    PISTON RING
    RIDING STYLE:
    OFF-ROAD
    PISTON SIZE METRIC:
    STANDARD
    $38.80
    Qty in Cart: 0
    Quantity:
    Price:
    $38.80
    Subtotal:
  • MOOSE RACING Motor Gasket Kit with Seal - KDX/JR 811416

    MOOSE RACING Motor Gasket Kit with Seal - KDX/JR 811416

    MOOSE RACING

    $43.01
    A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise your work—Moose Racing delivers OEM-quality components at a fraction of dealer pricing. This...
    09340485
    SKU:
    09340485
    Availability:
    Ships Same Business Day
    Weight:
    0.20 LBS
    $43.01
    Qty in Cart: 0
    Quantity:
    Price:
    $43.01
    Subtotal:
  • MOOSE RACING Top End Gasket Kit - RM125 810550

    MOOSE RACING Top End Gasket Kit - RM125 810550

    MOOSE RACING

    $31.50
    When you're rebuilding an RM125 top end, every gasket and seal matters—a single leak or failure can compromise your entire engine. The MOOSE RACING Top End Gasket Kit delivers OEM-quality seals and...
    09340486
    SKU:
    09340486
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    PRODUCT NAME:
    GASKET
    TYPE:
    TOP END
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $31.50
    Qty in Cart: 0
    Quantity:
    Price:
    $31.50
    Subtotal:
  • MOOSE RACING Complete Motor Gasket Kit - RM125 808550

    MOOSE RACING Complete Motor Gasket Kit - RM125 808550

    MOOSE RACING

    $83.24
    A complete engine and transmission rebuild demands gaskets and seals that won't fail under load—and OEM replacements can devastate your budget. The MOOSE RACING Complete Motor Gasket Kit gives you...
    09340487
    SKU:
    09340487
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    TYPE:
    COMPLETE
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    PRODUCT NAME:
    GASKET
    TYPE:
    ENGINE
    $83.24
    Qty in Cart: 0
    Quantity:
    Price:
    $83.24
    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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