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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 - 8.90 x 2.36 - 5 pack MSE5PK890236

    MOOSE RACING Valve Shim - 8.90 x 2.36 - 5 pack MSE5PK890236

    MOOSE RACING

    $10.95
    Precision valve train maintenance demands the right shims on hand—and these MOOSE RACING forged steel shims eliminate guesswork during critical adjustments. Whether you're dialing in clearances on a race engine or maintaining a high-mileage build, having...
    09261921
    SKU:
    09261921
    Availability:
    Ships Same Business Day
    Weight:
    0.02 LBS
    TYPE:
    VALVE
    VALVE SHIM THICKNESS METRIC:
    2.36 MM
    MATERIAL:
    ROLLED
    OUTSIDE DIAMETER METRIC:
    8.90 MM
    PRODUCT NAME:
    SHIM
    RIDING STYLE:
    SNOW
    UNITS:
    5 PACK
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    RIDING STYLE:
    UTV
    RIDING STYLE:
    WATERCRAFT
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    ATV
    RIDING STYLE:
    STREET
    $10.95
    Qty in Cart: 0
    Quantity:
    Price:
    $10.95
    Subtotal:
  • MOOSE RACING Valve Shim - 8.90 x 2.52 - 5 pack MSE5PK890252

    MOOSE RACING Valve Shim - 8.90 x 2.52 - 5 pack MSE5PK890252

    MOOSE RACING

    $10.95
    Maintaining precise valve clearances is critical to engine performance and longevity—even a few thousandths of an inch off can cause loss of power, increased wear, or catastrophic failure. The MOOSE RACING 8.90 x 2.52 Valve Shim 5-pack gives you a...
    09261925
    SKU:
    09261925
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    MATERIAL:
    ROLLED
    OUTSIDE DIAMETER METRIC:
    8.90 MM
    RIDING STYLE:
    ATV
    TYPE:
    VALVE
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    VALVE SHIM THICKNESS METRIC:
    2.52 MM
    PRODUCT NAME:
    SHIM
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    SNOW
    RIDING STYLE:
    STREET
    RIDING STYLE:
    WATERCRAFT
    UNITS:
    5 PACK
    RIDING STYLE:
    UTV
    $10.95
    Qty in Cart: 0
    Quantity:
    Price:
    $10.95
    Subtotal:
  • MOOSE RACING Valve Shim - 8.90 x 2.56 - 5 pack MSE5PK890256

    MOOSE RACING Valve Shim - 8.90 x 2.56 - 5 pack MSE5PK890256

    MOOSE RACING

    $10.95
    Maintaining precise valve clearances is critical to engine performance and longevity, and having quality shims on hand eliminates guesswork during valve train service. These MOOSE RACING valve shims are forged from 4140 cold rolled steel—not...
    09261926
    SKU:
    09261926
    Availability:
    Ships Same Business Day
    Weight:
    0.02 LBS
    MATERIAL:
    ROLLED
    MATERIAL:
    STEEL
    OUTSIDE DIAMETER METRIC:
    8.90 MM
    RIDING STYLE:
    UTV
    RIDING STYLE:
    WATERCRAFT
    TYPE:
    VALVE
    VALVE SHIM THICKNESS METRIC:
    2.56 MM
    PRODUCT NAME:
    SHIM
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    SNOW
    RIDING STYLE:
    STREET
    UNITS:
    5 PACK
    RIDING STYLE:
    ATV
    RIDING STYLE:
    OFF-ROAD
    $10.95
    Qty in Cart: 0
    Quantity:
    Price:
    $10.95
    Subtotal:
  • MOOSE RACING Water Pump Rebuild Kit 821412

    MOOSE RACING Water Pump Rebuild Kit 821412

    MOOSE RACING

    $43.28
    A failing water pump can strand you mid-season or compromise engine temperatures under sustained load. The MOOSE RACING Water Pump Rebuild Kit 821412 gives you a cost-effective alternative to replacing the entire assembly, restoring OEM performance with...
    09345214
    SKU:
    09345214
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    TYPE:
    WATER PUMP
    UNITS:
    KIT
    PRODUCT NAME:
    REPAIR KIT
    RIDING STYLE:
    OFF-ROAD
    $43.28
    Qty in Cart: 0
    Quantity:
    Price:
    $43.28
    Subtotal:
  • MOOSE RACING Water Pump Rebuild Kit 821417

    MOOSE RACING Water Pump Rebuild Kit 821417

    MOOSE RACING

    $43.28
    A failing water pump can compromise your entire cooling system and leave you stranded on track or trail. This MOOSE RACING rebuild kit supplies every gasket, seal, bearing, and snap ring needed to restore your water pump to OEM specifications without the...
    09345215
    SKU:
    09345215
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    RIDING STYLE:
    OFF-ROAD
    PRODUCT NAME:
    REPAIR KIT
    TYPE:
    WATER PUMP
    UNITS:
    KIT
    $43.28
    Qty in Cart: 0
    Quantity:
    Price:
    $43.28
    Subtotal:
  • MOOSE RACING Water Pump Rebuild Kit 821549

    MOOSE RACING Water Pump Rebuild Kit 821549

    MOOSE RACING

    $41.62
    Water pump failure leaves you stranded—and rebuilding with OEM-quality components is far more cost-effective than replacement. The MOOSE RACING Water Pump Rebuild Kit 821549 supplies every gasket, seal, bearing, and snap ring needed to restore your pump...
    09345239
    SKU:
    09345239
    Availability:
    Ships Same Business Day
    Weight:
    0.20 LBS
    PRODUCT NAME:
    REPAIR KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    TYPE:
    WATER PUMP
    $41.62
    Qty in Cart: 0
    Quantity:
    Price:
    $41.62
    Subtotal:
  • MOOSE RACING Water Pump Rebuild Kit 821550

    MOOSE RACING Water Pump Rebuild Kit 821550

    MOOSE RACING

    $41.30
    A failing water pump compromises your engine's cooling system, risking catastrophic overheating during aggressive track sessions or extended high-performance driving. Rather than replacing the entire unit, this MOOSE RACING rebuild kit restores your...
    09345240
    SKU:
    09345240
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    PRODUCT NAME:
    REPAIR KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    TYPE:
    WATER PUMP
    $41.30
    Qty in Cart: 0
    Quantity:
    Price:
    $41.30
    Subtotal:
  • MOOSE RACING Water Pump Rebuild Kit 821567

    MOOSE RACING Water Pump Rebuild Kit 821567

    MOOSE RACING

    $27.78
    A failing water pump compromises cooling system integrity and risks catastrophic engine damage. This complete rebuild kit lets you restore your water pump to OEM specifications without the expense of replacing the entire assembly. Whether you're...
    09345241
    SKU:
    09345241
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    PRODUCT NAME:
    REPAIR KIT
    TYPE:
    WATER PUMP
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $27.78
    Qty in Cart: 0
    Quantity:
    Price:
    $27.78
    Subtotal:
  • MOOSE RACING Water Pump Rebuild Kit 821587

    MOOSE RACING Water Pump Rebuild Kit 821587

    MOOSE RACING

    $35.70
    A failing water pump compromises engine cooling efficiency and risks catastrophic overheating. This comprehensive rebuild kit from MOOSE RACING supplies every gasket, seal, bearing, and snap ring needed to restore your water pump to OEM...
    09345246
    SKU:
    09345246
    Availability:
    Ships Same Business Day
    Weight:
    0.20 LBS
    PRODUCT NAME:
    REPAIR KIT
    TYPE:
    WATER PUMP
    UNITS:
    KIT
    RIDING STYLE:
    OFF-ROAD
    $35.70
    Qty in Cart: 0
    Quantity:
    Price:
    $35.70
    Subtotal:
  • MOOSE RACING Water Pump Rebuild Kit 821590

    MOOSE RACING Water Pump Rebuild Kit 821590

    MOOSE RACING

    $38.72
    A failing water pump can sideline your engine and leave you stranded. This complete rebuild kit from MOOSE RACING includes every gasket, seal, bearing, and O-ring needed to restore your water pump to factory specifications—saving you the cost and...
    09345247
    SKU:
    09345247
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    TYPE:
    WATER PUMP
    UNITS:
    KIT
    PRODUCT NAME:
    REPAIR KIT
    RIDING STYLE:
    OFF-ROAD
    $38.72
    Qty in Cart: 0
    Quantity:
    Price:
    $38.72
    Subtotal:
  • MOOSE RACING Head Cover Gasket - Suzuki 817907

    MOOSE RACING Head Cover Gasket - Suzuki 817907

    MOOSE RACING

    $25.91
    A leaking valve cover gasket compromises engine performance and creates a messy engine bay. OEM gaskets come at premium pricing, but Moose Racing delivers genuine replacement quality at a fraction of the cost. This U.S.-made gasket maintains reliable...
    09346174
    SKU:
    09346174
    Availability:
    Ships Same Business Day
    Weight:
    0.14 LBS
    MATERIAL:
    RUBBER
    RIDING STYLE:
    OFF-ROAD
    PRODUCT NAME:
    GASKET
    TYPE:
    VALVE COVER
    UNITS:
    EACH
    $25.91
    Qty in Cart: 0
    Quantity:
    Price:
    $25.91
    Subtotal:
  • MOOSE RACING Head Cover Gasket - Honda 817932

    MOOSE RACING Head Cover Gasket - Honda 817932

    MOOSE RACING

    $18.41
    Factory valve cover gaskets command premium pricing, but Moose Racing delivers OEM-quality seals at a fraction of the cost. This head cover gasket maintains a reliable seal under engine heat and pressure cycles, preventing oil leakage that can compromise...
    09346179
    SKU:
    09346179
    Availability:
    Ships Same Business Day
    Weight:
    0.11 LBS
    TYPE:
    VALVE COVER
    MATERIAL:
    RUBBER
    RIDING STYLE:
    OFF-ROAD
    PRODUCT NAME:
    GASKET
    UNITS:
    EACH
    $18.41
    Qty in Cart: 0
    Quantity:
    Price:
    $18.41
    Subtotal:
  • MOOSE RACING Outer Clutch Cover Gasket 817943

    MOOSE RACING Outer Clutch Cover Gasket 817943

    MOOSE RACING

    $10.87
    A leaking clutch cover gasket compromises engine sealing and invites oil contamination into critical drivetrain components. The MOOSE RACING Outer Clutch Cover Gasket 817943 delivers OEM-equivalent fitment and reliability at a fraction of OEM pricing,...
    09346180
    SKU:
    09346180
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    CLUTCH COVER
    PRODUCT NAME:
    GASKET
    UNITS:
    EACH
    $10.87
    Qty in Cart: 0
    Quantity:
    Price:
    $10.87
    Subtotal:
  • MOOSE RACING Gasket Set with Seals - Yamaha 811977

    MOOSE RACING Gasket Set with Seals - Yamaha 811977

    MOOSE RACING

    $133.72
    Engine gasket sets are critical for maintaining compression, preventing fluid leaks, and ensuring reliable performance—especially in high-demand racing applications where even minor seal failures can sideline your machine. The MOOSE RACING Gasket Set...
    09346929
    SKU:
    09346929
    Availability:
    Ships Same Business Day
    Weight:
    0.25 LBS
    UNITS:
    SET
    RIDING STYLE:
    OFF-ROAD
    PRODUCT NAME:
    GASKET SET
    $133.72
    Qty in Cart: 0
    Quantity:
    Price:
    $133.72
    Subtotal:
  • MOOSE RACING Gasket Clutch Inner - Yamaha 816082

    MOOSE RACING Gasket Clutch Inner - Yamaha 816082

    MOOSE RACING

    $13.91
    A worn or damaged clutch gasket compromises your engine's sealing integrity, leading to oil leaks and potential power loss—especially critical in high-rpm racing environments. The MOOSE RACING Gasket Clutch Inner is engineered to restore a factory-tight...
    09346930
    SKU:
    09346930
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    UNITS:
    EACH
    PRODUCT NAME:
    GASKET
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    CLUTCH INNER
    $13.91
    Qty in Cart: 0
    Quantity:
    Price:
    $13.91
    Subtotal:
  • MOOSE RACING Ignition Cover Gasket 816151

    MOOSE RACING Ignition Cover Gasket 816151

    MOOSE RACING

    $7.28
    A worn or damaged ignition cover gasket compromises engine sealing, risking oil leakage and potential internal contamination—exactly what you can't afford during competition or high-mileage operation. The MOOSE RACING Ignition Cover Gasket delivers...
    09346933
    SKU:
    09346933
    Availability:
    Ships Same Business Day
    Weight:
    0.08 LBS
    UNITS:
    EACH
    PRODUCT NAME:
    GASKET
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    IGNITION COVER
    $7.28
    Qty in Cart: 0
    Quantity:
    Price:
    $7.28
    Subtotal:
  • MOOSE RACING Ignition Cover Gasket 816178

    MOOSE RACING Ignition Cover Gasket 816178

    MOOSE RACING

    $10.95
    A properly sealed ignition cover is critical to maintaining engine reliability and preventing oil seepage that can compromise electrical components. The MOOSE RACING Ignition Cover Gasket 816178 delivers OEM-equivalent sealing performance with the...
    09346935
    SKU:
    09346935
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    TYPE:
    IGNITION COVER
    PRODUCT NAME:
    GASKET
    UNITS:
    EACH
    RIDING STYLE:
    OFF-ROAD
    $10.95
    Qty in Cart: 0
    Quantity:
    Price:
    $10.95
    Subtotal:
  • MOOSE RACING Motor Gasket Kit with Seal - 350SXF 811339

    MOOSE RACING Motor Gasket Kit with Seal - 350SXF 811339

    MOOSE RACING

    $165.87
    A complete engine and transmission rebuild demands precision-fit gaskets and seals—any compromise here leads to leaks, performance loss, and costly rework. The MOOSE RACING Motor Gasket Kit delivers OEM-quality sealing at a fraction of dealership...
    09342210
    SKU:
    09342210
    Availability:
    Ships Same Business Day
    Weight:
    0.56 LBS
    $165.87
    Qty in Cart: 0
    Quantity:
    Price:
    $165.87
    Subtotal:
  • MOOSE RACING Motor Gasket Kit with Seal - RMZ250 811567

    MOOSE RACING Motor Gasket Kit with Seal - RMZ250 811567

    MOOSE RACING

    $175.51
    A complete engine and transmission rebuild requires precision-fit gaskets and seals—compromising on quality means risking oil leaks, compression loss, and premature wear. The MOOSE RACING Motor Gasket Kit delivers OEM-equivalent performance at a fraction...
    09342211
    SKU:
    09342211
    Availability:
    Ships Same Business Day
    Weight:
    0.49 LBS
    $175.51
    Qty in Cart: 0
    Quantity:
    Price:
    $175.51
    Subtotal:
  • MOOSE RACING Motor Gasket Kit with Seal - YZ450F 811689

    MOOSE RACING Motor Gasket Kit with Seal - YZ450F 811689

    MOOSE RACING

    $194.87
    A complete engine and transmission rebuild demands precision-fit gaskets and seals—compromising on quality here risks leaks, contamination, and catastrophic failure. The MOOSE RACING Motor Gasket Kit eliminates guesswork by providing every gasket and...
    09342212
    SKU:
    09342212
    Availability:
    Ships Same Business Day
    Weight:
    0.26 LBS
    TYPE:
    ENGINE
    PRODUCT NAME:
    GASKET
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    UNITS:
    KIT
    $194.87
    Qty in Cart: 0
    Quantity:
    Price:
    $194.87
    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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