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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
  • KIBBLEWHITE Intake Valve 30-3116

    KIBBLEWHITE Intake Valve 30-3116

    KIBBLEWHITE

    $37.55
    Intake valve performance directly impacts combustion efficiency, fuel economy, and horsepower output—making quality valve selection critical for any engine build. The KIBBLEWHITE Black Diamond™ 30-3116 combines precision engineering with superior...
    KW303116
    SKU:
    KW303116
    Availability:
    Ships Same Business Day
    Weight:
    0.13 LBS
    MATERIAL:
    STAINLESS STEEL
    MODEL:
    BLACK DIAMOND™
    STEM DIAMETER IMPERIAL:
    0.2156'
    HEAD DIAMETER METRIC:
    43.00 MM
    LENGTH IMPERIAL:
    4.020'
    RIDING STYLE:
    ATV
    UNITS:
    EACH
    PRODUCT NAME:
    VALVE
    TULIP ANGLE:
    20°
    APPLICATION:
    INTAKE
    RIDING STYLE:
    OFF-ROAD
    $37.55
    Qty in Cart: 0
    Quantity:
    Price:
    $37.55
    Subtotal:
  • KIBBLEWHITE Exhaust Valve Guide 82-82230

    KIBBLEWHITE Exhaust Valve Guide 82-82230

    KIBBLEWHITE

    $26.43
    Valve guide wear is one of the most common causes of compression loss and oil consumption in high-mileage engines. The KIBBLEWHITE 82-82230 Exhaust Valve Guide delivers the thermal conductivity and durability you need to maintain precise valve sealing...
    09261176
    SKU:
    09261176
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    OUTSIDE DIAMETER IMPERIAL:
    0.4531'
    MATERIAL:
    C630 BRONZE
    PRODUCT NAME:
    VALVE GUIDE
    APPLICATION:
    EXHAUST
    INSIDE DIAMETER IMPERIAL:
    0.2355'
    RIDING STYLE:
    ATV
    SIZE IMPERIAL:
    STANDARD
    UNITS:
    EACH
    $26.43
    Qty in Cart: 0
    Quantity:
    Price:
    $26.43
    Subtotal:
  • KIBBLEWHITE Intake Valve 82-82212

    KIBBLEWHITE Intake Valve 82-82212

    KIBBLEWHITE

    $37.55
    Intake valves are the gatekeepers of your engine's breathing efficiency—and a worn or substandard valve directly compromises power delivery and reliability. The Kibblewhite Black Diamond™ intake valve delivers measurable gains in flow consistency and...
    09261178
    SKU:
    09261178
    Availability:
    Ships Same Business Day
    Weight:
    0.11 LBS
    APPLICATION:
    INTAKE
    TULIP ANGLE:
    25°
    HEAD DIAMETER METRIC:
    35.00 MM
    LENGTH IMPERIAL:
    4.510'
    RIDING STYLE:
    ATV
    UNITS:
    EACH
    MATERIAL:
    STAINLESS STEEL
    MODEL:
    BLACK DIAMOND™
    PRODUCT NAME:
    VALVE
    STEM DIAMETER IMPERIAL:
    0.2357'
    $37.55
    Qty in Cart: 0
    Quantity:
    Price:
    $37.55
    Subtotal:
  • KIBBLEWHITE Exhaust Valve 82-82216

    KIBBLEWHITE Exhaust Valve 82-82216

    KIBBLEWHITE

    $37.55
    Exhaust valves endure extreme thermal and mechanical stress—OEM components often fail prematurely, compromising engine efficiency and reliability. The KIBBLEWHITE Black Diamond™ valve delivers the durability and precision engineered for high-performance...
    09261180
    SKU:
    09261180
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    APPLICATION:
    EXHAUST
    HEAD DIAMETER METRIC:
    30.00 MM
    RIDING STYLE:
    ATV
    LENGTH IMPERIAL:
    4.555'
    UNITS:
    EACH
    MATERIAL:
    STAINLESS STEEL
    PRODUCT NAME:
    VALVE
    STEM DIAMETER IMPERIAL:
    0.2352'
    TULIP ANGLE:
    11°
    MODEL:
    BLACK DIAMOND™
    $37.55
    Qty in Cart: 0
    Quantity:
    Price:
    $37.55
    Subtotal:
  • KIBBLEWHITE Intake/Exhaust Valve Guide 30-4069

    KIBBLEWHITE Intake/Exhaust Valve Guide 30-4069

    KIBBLEWHITE

    $26.89
    Valve guide wear is one of the most common causes of oil consumption, poor ring sealing, and valve seat degradation in high-performance engines. The KIBBLEWHITE 30-4069 Intake/Exhaust Valve Guide delivers the thermal conductivity and wear resistance...
    KW304069
    SKU:
    KW304069
    Availability:
    Ships Same Business Day
    Weight:
    0.25 LBS
    INSIDE DIAMETER IMPERIAL:
    0.2155'
    RIDING STYLE:
    OFF-ROAD
    APPLICATION:
    INTAKE
    MATERIAL:
    AMPCO-45
    PRODUCT NAME:
    VALVE GUIDE
    OUTSIDE DIAMETER IMPERIAL:
    0.4372'
    APPLICATION:
    EXHAUST
    SIZE IMPERIAL:
    STANDARD
    UNITS:
    EACH
    $26.89
    Qty in Cart: 0
    Quantity:
    Price:
    $26.89
    Subtotal:
  • KIBBLEWHITE Valve Seat 10-SB250

    KIBBLEWHITE Valve Seat 10-SB250

    KIBBLEWHITE

    $30.30
    If you're running titanium valves in a high-performance engine, your valve seats need to match that precision. KIBBLEWHITE's copper-based seats deliver the thermal conductivity and wear resistance required to keep up with aggressive valve timing and...
    09261619
    SKU:
    09261619
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    UNITS:
    EACH
    APPLICATION:
    INTAKE
    MATERIAL:
    TITANIUM
    PRODUCT NAME:
    VALVE SEAT
    VALVE SEAT HEIGHT METRIC:
    9.00 MM
    INSIDE DIAMETER METRIC:
    17.00 MM
    OUTSIDE DIAMETER METRIC:
    25.00 MM
    RIDING STYLE:
    OFF-ROAD
    Qty in Cart: 0
    Quantity:
    Price:
    $30.30
    Subtotal:
  • KIBBLEWHITE Valve Seat 10-SB280

    KIBBLEWHITE Valve Seat 10-SB280

    KIBBLEWHITE

    $30.30
    If you're running titanium valves in a high-performance engine, valve seat material directly impacts your engine's thermal stability, durability, and longevity under sustained boost or high RPM. KIBBLEWHITE's copper-based valve seats were engineered...
    09261620
    SKU:
    09261620
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    PRODUCT NAME:
    VALVE SEAT
    APPLICATION:
    EXHAUST
    VALVE SEAT HEIGHT METRIC:
    9.50 MM
    OUTSIDE DIAMETER METRIC:
    28.00 MM
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    INSIDE DIAMETER METRIC:
    20.00 MM
    MATERIAL:
    TITANIUM
    $30.30
    Qty in Cart: 0
    Quantity:
    Price:
    $30.30
    Subtotal:
  • KIBBLEWHITE Valve Seat 10-SB350

    KIBBLEWHITE Valve Seat 10-SB350

    KIBBLEWHITE

    $34.71
    If you're running titanium valves in a high-performance application, valve seat material matters—a lot. KIBBLEWHITE's copper-based seats deliver superior thermal conductivity and wear resistance, keeping your engine reliable across extended racing duty...
    09261626
    SKU:
    09261626
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    MATERIAL:
    TITANIUM
    INSIDE DIAMETER METRIC:
    26.00 MM
    RIDING STYLE:
    OFF-ROAD
    APPLICATION:
    EXHAUST
    OUTSIDE DIAMETER METRIC:
    35.00 MM
    PRODUCT NAME:
    VALVE SEAT
    UNITS:
    EACH
    VALVE SEAT HEIGHT METRIC:
    11.00 MM
    $34.71
    Qty in Cart: 0
    Quantity:
    Price:
    $34.71
    Subtotal:
  • KIBBLEWHITE Valve Seat 10-SB385

    KIBBLEWHITE Valve Seat 10-SB385

    KIBBLEWHITE

    $40.81
    If you're running titanium valves in a high-performance engine, your valve seats need to match that precision. The KIBBLEWHITE 10-SB385 is purpose-built to handle the thermal demands and wear patterns titanium creates, ensuring reliable seating and...
    09261627
    SKU:
    09261627
    Availability:
    Ships Same Business Day
    Weight:
    0.08 LBS
    INSIDE DIAMETER METRIC:
    29.00 MM
    MATERIAL:
    TITANIUM
    VALVE SEAT HEIGHT METRIC:
    11.00 MM
    OUTSIDE DIAMETER METRIC:
    38.50 MM
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE SEAT
    $40.81
    Qty in Cart: 0
    Quantity:
    Price:
    $40.81
    Subtotal:
  • KIBBLEWHITE Valve Seat 10-SB390

    KIBBLEWHITE Valve Seat 10-SB390

    KIBBLEWHITE

    $40.81
    If you're running titanium valves in a high-performance engine, your valve seats are the critical interface between extreme heat and precision engineering. KIBBLEWHITE's copper-based seat design delivers the thermal conductivity and wear resistance...
    09261628
    SKU:
    09261628
    Availability:
    Ships Same Business Day
    Weight:
    0.09 LBS
    INSIDE DIAMETER METRIC:
    30.00 MM
    MATERIAL:
    TITANIUM
    OUTSIDE DIAMETER METRIC:
    39.00 MM
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    VALVE SEAT HEIGHT METRIC:
    11.00 MM
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    VALVE SEAT
    $40.81
    Qty in Cart: 0
    Quantity:
    Price:
    $40.81
    Subtotal:
  • KIBBLEWHITE Cast Iron Valve Seat 10-SC290

    KIBBLEWHITE Cast Iron Valve Seat 10-SC290

    KIBBLEWHITE

    $8.24
    If you're running high-RPM applications or alternative fuels—whether it's nitrous, forced induction, or methanol—your valve seats need to withstand extreme thermal stress and microwelding without recession. The KIBBLEWHITE Cast Iron Valve Seat 10-SC290...
    09261631
    SKU:
    09261631
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    INSIDE DIAMETER METRIC:
    21.00 MM
    RIDING STYLE:
    ATV
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    VALVE SEAT HEIGHT METRIC:
    9.50 MM
    APPLICATION:
    INTAKE
    HEAD DIAMETER METRIC:
    29.00 MM
    MATERIAL:
    STEEL
    OUTSIDE DIAMETER METRIC:
    29.00 MM
    PRODUCT NAME:
    VALVE SEAT
    $8.24
    Qty in Cart: 0
    Quantity:
    Price:
    $8.24
    Subtotal:
  • KIBBLEWHITE Cast Iron Valve Seat 10-SC310

    KIBBLEWHITE Cast Iron Valve Seat 10-SC310

    KIBBLEWHITE

    $8.49
    Valve seat recession is one of the most insidious problems in high-performance engines—it silently erodes compression, destroys your power curve, and forces expensive rebuilds. The KIBBLEWHITE Cast Iron Valve Seat 10-SC310 eliminates this failure mode...
    09261632
    SKU:
    09261632
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    INSIDE DIAMETER METRIC:
    23.00 MM
    VALVE SEAT HEIGHT METRIC:
    9.50 MM
    HEAD DIAMETER METRIC:
    31.00 MM
    MATERIAL:
    STEEL
    OUTSIDE DIAMETER METRIC:
    31.00 MM
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    VALVE SEAT
    RIDING STYLE:
    ATV
    $8.49
    Qty in Cart: 0
    Quantity:
    Price:
    $8.49
    Subtotal:
  • KIBBLEWHITE Cast Iron Valve Seat 10-SC390

    KIBBLEWHITE Cast Iron Valve Seat 10-SC390

    KIBBLEWHITE

    $9.57
    Valve seat recession and microwelding are silent killers in high-performance engines—they compromise combustion efficiency, increase blow-by, and shorten engine life. The KIBBLEWHITE Cast Iron Valve Seat 10-SC390 uses advanced powdered metal technology...
    09261638
    SKU:
    09261638
    Availability:
    Ships Same Business Day
    Weight:
    0.08 LBS
    PRODUCT NAME:
    VALVE SEAT
    UNITS:
    EACH
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    APPLICATION:
    INTAKE
    INSIDE DIAMETER METRIC:
    30.00 MM
    OUTSIDE DIAMETER METRIC:
    39.00 MM
    HEAD DIAMETER METRIC:
    39.00 MM
    VALVE SEAT HEIGHT METRIC:
    10.00 MM
    $9.57
    Qty in Cart: 0
    Quantity:
    Price:
    $9.57
    Subtotal:
  • KIBBLEWHITE Spring Kit - .440" 30-31250

    KIBBLEWHITE Spring Kit - .440" 30-31250

    KIBBLEWHITE

    $207.83
    Valve spring performance directly impacts your engine's ability to maintain precise valve timing under high RPM conditions. The KIBBLEWHITE Spring Kit delivers consistent lift and closure across the entire rev range, preventing valve float that...
    09261640
    SKU:
    09261640
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    SPRING KIT
    SPRING LIFT IMPERIAL:
    0.440'
    SPRING OPEN PRESSURE:
    INTAKE 147 LB, EXHAUST 203 LB
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    EXHAUST
    TYPE:
    VALVE
    MATERIAL:
    TITANIUM
    $207.83
    Qty in Cart: 0
    Quantity:
    Price:
    $207.83
    Subtotal:
  • KIBBLEWHITE Exhaust Valve 30-31266

    KIBBLEWHITE Exhaust Valve 30-31266

    KIBBLEWHITE

    $31.01
    Exhaust valves are critical to engine reliability and performance—they endure extreme heat cycling and high-velocity gas flow that demands superior material integrity. KIBBLEWHITE's Black Diamond™ valves are engineered to withstand these demanding...
    09261643
    SKU:
    09261643
    Availability:
    Ships Same Business Day
    Weight:
    0.11 LBS
    APPLICATION:
    EXHAUST
    HEAD DIAMETER METRIC:
    30.00 MM
    LENGTH IMPERIAL:
    3.175'
    TULIP ANGLE:
    20°
    MATERIAL:
    STAINLESS STEEL
    PRODUCT NAME:
    VALVE
    STEM DIAMETER IMPERIAL:
    0.1955'
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    MODEL:
    BLACK DIAMOND™
    $31.01
    Qty in Cart: 0
    Quantity:
    Price:
    $31.01
    Subtotal:
  • KIBBLEWHITE Exhaust Valve 40-40416

    KIBBLEWHITE Exhaust Valve 40-40416

    KIBBLEWHITE

    $31.01
    Exhaust valves endure extreme thermal cycling and chemical exposure—factory components often succumb to carbon buildup, corrosion, and premature wear. The Kibblewhite Black Diamond™ Exhaust Valve (40-40416) is engineered to outlast OEM parts by combining...
    09261651
    SKU:
    09261651
    Availability:
    Ships Same Business Day
    Weight:
    0.06 LBS
    RIDING STYLE:
    UTV
    MATERIAL:
    STAINLESS STEEL
    MODEL:
    BLACK DIAMOND™
    PRODUCT NAME:
    VALVE
    STEM DIAMETER IMPERIAL:
    0.1955'
    HEAD DIAMETER METRIC:
    26.00 MM
    LENGTH IMPERIAL:
    3.655'
    APPLICATION:
    EXHAUST
    RIDING STYLE:
    ATV
    TULIP ANGLE:
    10°
    UNITS:
    EACH
    $31.01
    Qty in Cart: 0
    Quantity:
    Price:
    $31.01
    Subtotal:
  • KIBBLEWHITE Valve Guide 40-40420

    KIBBLEWHITE Valve Guide 40-40420

    KIBBLEWHITE

    $19.83
    Valve guide wear is one of the most overlooked causes of oil consumption and compression loss in high-performance engines. The KIBBLEWHITE Valve Guide 40-40420 uses premium Ampco-45 composition to deliver the thermal conductivity and wear resistance your...
    09261653
    SKU:
    09261653
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    INSIDE DIAMETER IMPERIAL:
    0.1955'
    RIDING STYLE:
    UTV
    APPLICATION:
    INTAKE
    OUTSIDE DIAMETER IMPERIAL:
    0.4160'
    PRODUCT NAME:
    VALVE GUIDE
    MATERIAL:
    C630 BRONZE
    APPLICATION:
    EXHAUST
    RIDING STYLE:
    ATV
    SIZE IMPERIAL:
    STANDARD
    UNITS:
    EACH
    $19.83
    Qty in Cart: 0
    Quantity:
    Price:
    $19.83
    Subtotal:
  • KIBBLEWHITE Exhaust Valve 60-60210H

    KIBBLEWHITE Exhaust Valve 60-60210H

    KIBBLEWHITE

    $37.55
    Exhaust valves experience extreme thermal and mechanical stress, and OEM units often succumb to wear, carbon buildup, and corrosion—compromising engine efficiency and reliability. The KIBBLEWHITE Black Diamond™ 60-60210H delivers precision-engineered...
    09261656
    SKU:
    09261656
    Availability:
    Ships Same Business Day
    Weight:
    0.11 LBS
    APPLICATION:
    INTAKE
    RIDING STYLE:
    OFF-ROAD
    TULIP ANGLE:
    20°
    MATERIAL:
    STAINLESS STEEL
    PRODUCT NAME:
    VALVE
    LENGTH IMPERIAL:
    3.120'
    UNITS:
    EACH
    HEAD DIAMETER METRIC:
    31.00 MM
    MODEL:
    BLACK DIAMOND™
    STEM DIAMETER IMPERIAL:
    0.1765'
    $37.55
    Qty in Cart: 0
    Quantity:
    Price:
    $37.55
    Subtotal:
  • KIBBLEWHITE Exhaust Valve 60-60213H

    KIBBLEWHITE Exhaust Valve 60-60213H

    KIBBLEWHITE

    $37.55
    If you're building a high-revving engine that demands reliability under extreme conditions, valve quality directly impacts combustion efficiency, longevity, and peak horsepower. KIBBLEWHITE's Black Diamond™ exhaust valves are engineered to withstand...
    09261658
    SKU:
    09261658
    Availability:
    Ships Same Business Day
    Weight:
    0.05 LBS
    HEAD DIAMETER METRIC:
    25.00 MM
    STEM DIAMETER IMPERIAL:
    0.1756'
    APPLICATION:
    EXHAUST
    MATERIAL:
    STAINLESS STEEL
    PRODUCT NAME:
    VALVE
    TULIP ANGLE:
    25°
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    LENGTH IMPERIAL:
    3.115'
    MODEL:
    BLACK DIAMOND™
    $37.55
    Qty in Cart: 0
    Quantity:
    Price:
    $37.55
    Subtotal:
  • KIBBLEWHITE Spring Kit - .445" 60-60500

    KIBBLEWHITE Spring Kit - .445" 60-60500

    KIBBLEWHITE

    $220.26
    Valve spring integrity directly impacts engine reliability and performance across the entire RPM band. This KIBBLEWHITE Spring Kit delivers precisely engineered spring rates and damping characteristics, ensuring consistent valve control whether you're...
    09261660
    SKU:
    09261660
    Availability:
    Ships Same Business Day
    Weight:
    0.45 LBS
    SPRING LIFT IMPERIAL:
    0.445'
    APPLICATION:
    EXHAUST
    TYPE:
    VALVE
    MATERIAL:
    TITANIUM
    PRODUCT NAME:
    SPRING KIT
    APPLICATION:
    INTAKE
    RIDING STYLE:
    OFF-ROAD
    SPRING OPEN PRESSURE:
    160 LB
    UNITS:
    KIT
    $220.26
    Qty in Cart: 0
    Quantity:
    Price:
    $220.26
    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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