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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
  • On Sale
    Cylinder Works Big Bore Cylinder Kit 295cc for Yamaha YZ250 1999-2023 21009-K01 Cylinder Works Big Bore Cylinder Kit 295cc for Yamaha YZ250 1999-2023 21009-K01

    Cylinder Works Big Bore Cylinder Kit 295cc for Yamaha YZ250 1999-2023 21009-K01

    CYLINDER WORKS

    MSRP: $1,195.95
    Now: $1,076.36
    Was: $1,195.95
    The Cylinder Works Big Bore Kit transforms your YZ250 into a more potent machine by increasing displacement to 295cc—delivering measurable gains in mid-range and peak power without sacrificing the reliability you depend on for consistent track...
    09311163
    SKU:
    09311163
    Availability:
    Ships Same Business Day
    Weight:
    8.71 LBS
    COLOR/FINISH:
    GRAY
    CYLINDER DIAMETER:
    72,00 MM
    ENGINE TYPE:
    2-STROKE
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    CYLINDER DIAMETER METRIC:
    72.00 MM
    DISPLACEMENT:
    295 CC
    OVERBORE METRIC:
    +5.60 MM
    PRODUCT NAME:
    CYLINDER KIT
    STYLE:
    BIG BORE
    MSRP: $1,195.95
    Now: $1,076.36
    Was: $1,195.95
    Qty in Cart: 0
    Quantity:
    Price:
    MSRP: $1,195.95
    Now: $1,076.36
    Was: $1,195.95
    Subtotal:
  • ACERBIS X-Power Kit - Black - Suzuki 2983330001

    ACERBIS X-Power Kit - Black - Suzuki 2983330001

    ACERBIS

    $76.95
    Crankcase damage from crashes or overheating can sideline your bike and drain your wallet. The ACERBIS X-Power Kit provides comprehensive protection for both your clutch and ignition crankcases while managing heat through strategically designed air...
    09402143
    SKU:
    09402143
    Availability:
    Ships Same Business Day
    Weight:
    1.47 LBS
    COLOR/FINISH:
    BLACK
    MATERIAL:
    METAL
    MATERIAL:
    PLASTIC
    RIDING STYLE:
    STREET
    MODEL:
    X-POWER
    TYPE:
    SIDE COVER
    PRODUCT NAME:
    X-POWER KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Black - Husqvarna/KTM 2983230001

    ACERBIS X-Power Kit - Black - Husqvarna/KTM 2983230001

    ACERBIS

    $76.95
    Off-road riding exposes your engine to constant threats—mud, debris, sand, and extreme heat that can compromise critical components. The ACERBIS X-Power Kit delivers comprehensive protection for your Husqvarna or KTM's clutch cover, water pump, lower...
    09402144
    SKU:
    09402144
    Availability:
    Ships Same Business Day
    Weight:
    1.45 LBS
    MODEL:
    X-POWER
    COLOR/FINISH:
    BLACK
    MATERIAL:
    PLASTIC
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Blue - Husqvarna/KTM 2983230003

    ACERBIS X-Power Kit - Blue - Husqvarna/KTM 2983230003

    ACERBIS

    $76.95
    Off-road riding exposes your engine to constant abuse—flying rocks, mud, water, and extreme heat can damage critical components like your clutch cover, water pump, and ignition system. The ACERBIS X-Power Kit provides comprehensive protection where it...
    09402145
    SKU:
    09402145
    Availability:
    Ships Same Business Day
    Weight:
    1.40 LBS
    COLOR/FINISH:
    BLUE
    MATERIAL:
    PLASTIC
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MODEL:
    X-POWER
    TYPE:
    SIDE COVER
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Black - Honda CRF 2982510001

    ACERBIS X-Power Kit - Black - Honda CRF 2982510001

    ACERBIS

    $76.95
    Your crankcase and clutch housing face constant abuse from impact, abrasion, and debris—especially in off-road conditions. The ACERBIS X-Power Kit provides direct OEM-fitment protection engineered to absorb impacts while maintaining optimal engine...
    09402146
    SKU:
    09402146
    Availability:
    Ships Same Business Day
    Weight:
    1.34 LBS
    MODEL:
    X-POWER
    COLOR/FINISH:
    BLACK
    RIDING STYLE:
    STREET
    UNITS:
    KIT
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    MATERIAL:
    NYLON
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Red - Honda CRF 2982510004

    ACERBIS X-Power Kit - Red - Honda CRF 2982510004

    ACERBIS

    $76.95
    Your crankcase and clutch housing face constant abuse from impacts, mud, sand, and debris—damage that translates to expensive repairs and downtime. The ACERBIS X-Power Kit provides OEM-fitted protection on both sides of your Honda CRF engine, using...
    09402147
    SKU:
    09402147
    Availability:
    Ships Same Business Day
    Weight:
    1.40 LBS
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    UNITS:
    KIT
    COLOR/FINISH:
    RED
    RIDING STYLE:
    STREET
    MODEL:
    X-POWER
    MATERIAL:
    NYLON
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Orange - Husqvarna/KTM 2983235226

    ACERBIS X-Power Kit - Orange - Husqvarna/KTM 2983235226

    ACERBIS

    $76.95
    Off-road riding exposes your engine to relentless punishment—mud, sand, rocks, and extreme heat all threaten critical components like your clutch cover, water pump, and ignition system. The ACERBIS X-Power Kit delivers comprehensive protection where it...
    09402148
    SKU:
    09402148
    Availability:
    Ships Same Business Day
    Weight:
    1.40 LBS
    COLOR/FINISH:
    ORANGE
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    TYPE:
    SIDE COVER
    MATERIAL:
    PLASTIC
    MODEL:
    X-POWER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Orange - Husqvarna/KTM 2981365226

    ACERBIS X-Power Kit - Orange - Husqvarna/KTM 2981365226

    ACERBIS

    $76.95
    Dirt bikes experience relentless punishment from mud, sand, and debris—and your engine covers shouldn't be the weak link. The ACERBIS X-Power Kit delivers comprehensive protection for your clutch, water pump, and ignition systems while maintaining...
    09402149
    SKU:
    09402149
    Availability:
    Ships Same Business Day
    Weight:
    1.40 LBS
    MATERIAL:
    BRASS
    PRODUCT NAME:
    X-POWER KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    COLOR/FINISH:
    ORANGE
    MODEL:
    X-POWER
    MATERIAL:
    NYLON
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Black - Husqvarna/KTM 2981360001

    ACERBIS X-Power Kit - Black - Husqvarna/KTM 2981360001

    ACERBIS

    $76.95
    If you're running a Husqvarna or KTM dirt bike, engine cover damage isn't just a cosmetic issue—it compromises protection for critical components like your clutch cover, water pump, and ignition system. The ACERBIS X-Power Kit shields these vulnerable...
    09402150
    SKU:
    09402150
    Availability:
    Ships Same Business Day
    Weight:
    1.40 LBS
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    BRASS
    PRODUCT NAME:
    X-POWER KIT
    MATERIAL:
    NYLON
    MODEL:
    X-POWER
    TYPE:
    SIDE COVER
    COLOR/FINISH:
    BLACK
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Blue - Husqvarna/KTM 2981360003

    ACERBIS X-Power Kit - Blue - Husqvarna/KTM 2981360003

    ACERBIS

    $76.95
    Dirt bike racing demands engine protection that actually performs under extreme conditions. The ACERBIS X-Power Kit shields your clutch cover, water pump, lower crankcase, and ignition system from the constant barrage of mud, sand, rocks, and debris that...
    09402151
    SKU:
    09402151
    Availability:
    Ships Same Business Day
    Weight:
    1.35 LBS
    MATERIAL:
    BRASS
    PRODUCT NAME:
    X-POWER KIT
    COLOR/FINISH:
    BLUE
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    NYLON
    MODEL:
    X-POWER
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Orange - Husqvarna/KTM 2981475226

    ACERBIS X-Power Kit - Orange - Husqvarna/KTM 2981475226

    ACERBIS

    $76.95
    Off-road riding subjects your engine to constant assault from mud, sand, and debris—a single uncovered section can lead to costly damage or catastrophic failure. The ACERBIS X-Power Kit provides comprehensive protection for your Husqvarna or KTM's most...
    09402152
    SKU:
    09402152
    Availability:
    Ships Same Business Day
    Weight:
    1.25 LBS
    COLOR/FINISH:
    ORANGE
    RIDING STYLE:
    STREET
    MATERIAL:
    BRASS
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    PRODUCT NAME:
    X-POWER KIT
    TYPE:
    SIDE COVER
    MATERIAL:
    NYLON
    MODEL:
    X-POWER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Black - Husqvarna/KTM 2981470001

    ACERBIS X-Power Kit - Black - Husqvarna/KTM 2981470001

    ACERBIS

    $76.95
    Off-road riding exposes your engine to constant punishment—mud, sand, rocks, and extreme temperatures degrade unprotected components quickly. The ACERBIS X-Power Kit shields your clutch cover, water pump, lower crankcase, and ignition cover with durable,...
    09402153
    SKU:
    09402153
    Availability:
    Ships Same Business Day
    Weight:
    1.30 LBS
    MATERIAL:
    BRASS
    PRODUCT NAME:
    X-POWER KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    COLOR/FINISH:
    BLACK
    RIDING STYLE:
    STREET
    MODEL:
    X-POWER
    MATERIAL:
    NYLON
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Blue - Husqvarna/KTM 2981470003

    ACERBIS X-Power Kit - Blue - Husqvarna/KTM 2981470003

    ACERBIS

    $76.95
    If you're running a Husqvarna or KTM two-stroke, engine case protection isn't optional—it's essential. The ACERBIS X-Power Kit shields your clutch cover, water pump, lower crankcase, and ignition cover from the constant barrage of rocks, mud, and debris...
    09402154
    SKU:
    09402154
    Availability:
    Ships Same Business Day
    Weight:
    0.65 LBS
    MODEL:
    X-POWER
    RIDING STYLE:
    STREET
    COLOR/FINISH:
    BLUE
    UNITS:
    KIT
    MATERIAL:
    BRASS
    PRODUCT NAME:
    X-POWER KIT
    RIDING STYLE:
    OFF-ROAD
    MATERIAL:
    NYLON
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Black - Yamaha YZ450F 2981870001

    ACERBIS X-Power Kit - Black - Yamaha YZ450F 2981870001

    ACERBIS

    $76.95
    Protect your YZ450F's most vulnerable components from the harsh realities of off-road riding. The ACERBIS X-Power Kit shields both your ignition and clutch crankcases from impacts, abrasion, and debris without compromising engine cooling or...
    09402156
    SKU:
    09402156
    Availability:
    Ships Same Business Day
    Weight:
    1.40 LBS
    MATERIAL:
    NYLON
    MODEL:
    X-POWER
    COLOR/FINISH:
    BLACK
    MATERIAL:
    BRASS
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    PRODUCT NAME:
    X-POWER KIT
    TYPE:
    SIDE COVER
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Blue - Yamaha YZ450F 2981870211

    ACERBIS X-Power Kit - Blue - Yamaha YZ450F 2981870211

    ACERBIS

    $76.95
    Dirt bike racing demands protection against the constant barrage of mud, sand, and debris—especially on your YZ450F's vulnerable crankcase components. The ACERBIS X-Power Kit shields both your ignition and clutch crankcases from impact and abrasion while...
    09402157
    SKU:
    09402157
    Availability:
    Ships Same Business Day
    Weight:
    1.46 LBS
    COLOR/FINISH:
    BLUE
    MODEL:
    X-POWER
    MATERIAL:
    NYLON
    TYPE:
    SIDE COVER
    MATERIAL:
    BRASS
    PRODUCT NAME:
    X-POWER KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Black - Gas Gas/Husqvarna/KTM 2983260001

    ACERBIS X-Power Kit - Black - Gas Gas/Husqvarna/KTM 2983260001

    ACERBIS

    $76.95
    When you're pushing your Gas Gas, Husqvarna, or KTM to its limits, unprotected engine covers become vulnerable to flying debris, mud, and impacts that can compromise critical components. The Acerbis X-Power Kit shields your clutch cover, water pump,...
    09402158
    SKU:
    09402158
    Availability:
    Ships Same Business Day
    Weight:
    1.30 LBS
    TYPE:
    SIDE COVER
    MODEL:
    X-POWER
    RIDING STYLE:
    STREET
    COLOR/FINISH:
    BLACK
    MATERIAL:
    PLASTIC
    UNITS:
    KIT
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    RIDING STYLE:
    OFF-ROAD
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Blue - Gas Gas/Husqvarna/KTM 2983260003

    ACERBIS X-Power Kit - Blue - Gas Gas/Husqvarna/KTM 2983260003

    ACERBIS

    $76.95
    Dirt bike racing demands protection that keeps up with your intensity—and the ACERBIS X-Power Kit delivers exactly that. Whether you're tackling rocky terrain, muddy trails, or high-speed desert runs, this kit shields your engine's most vulnerable...
    09402159
    SKU:
    09402159
    Availability:
    Ships Same Business Day
    Weight:
    1.25 LBS
    RIDING STYLE:
    STREET
    MATERIAL:
    PLASTIC
    MODEL:
    X-POWER
    TYPE:
    SIDE COVER
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    COLOR/FINISH:
    BLUE
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • ACERBIS X-Power Kit - Orange - Gas Gas/Husqvarna/KTM 2983265226

    ACERBIS X-Power Kit - Orange - Gas Gas/Husqvarna/KTM 2983265226

    ACERBIS

    $76.95
    Offroad riding exposes your engine to relentless punishment—flying rocks, mud, water, and debris that compromise critical components. The ACERBIS X-Power Kit shields your clutch cover, water pump, lower crankcase, and ignition cover with durable...
    09402160
    SKU:
    09402160
    Availability:
    Ships Same Business Day
    Weight:
    1.40 LBS
    MATERIAL:
    PLASTIC
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    RIDING STYLE:
    STREET
    MODEL:
    X-POWER
    TYPE:
    SIDE COVER
    COLOR/FINISH:
    ORANGE
    MATERIAL:
    STEEL
    PRODUCT NAME:
    X-POWER KIT
    $76.95
    Qty in Cart: 0
    Quantity:
    Price:
    $76.95
    Subtotal:
  • MOOSE RACING Piston Kit MX2045

    MOOSE RACING Piston Kit MX2045

    MOOSE RACING

    $386.95
    If you're pushing your engine to the limit, your stock pistons aren't built for it. The MOOSE RACING Piston Kit MX2045 combines race-proven forging technology with advanced stress-relief engineering to deliver the durability, power, and reliability...
    09106482
    SKU:
    09106482
    Availability:
    Ships Same Business Day
    Weight:
    1.15 LBS
    $386.95
    Qty in Cart: 0
    Quantity:
    Price:
    $386.95
    Subtotal:
  • MOOSE RACING Piston Kit MP4028

    MOOSE RACING Piston Kit MP4028

    MOOSE RACING

    $326.95
    High-performance racing demands pistons engineered for extreme conditions—and the MOOSE RACING Piston Kit MP4028 delivers the strength, durability, and power output required to dominate on the track. Built with X-style and fully-boxed race forgings,...
    09106485
    SKU:
    09106485
    Availability:
    Ships Same Business Day
    Weight:
    1.41 LBS
    $326.95
    Qty in Cart: 0
    Quantity:
    Price:
    $326.95
    Subtotal:
  • Total: items /

Adding your products to cart

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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