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Dirt Bike Engine Valves and Parts

Dirt Bike Engine Valves and Parts

Dirt Bike Engine Valves and Parts

Dirt Bike Engine Valves & Parts: Kibblewhite Black Diamond Exhaust Valves & Spring Kits at JJ Motorsports

Upgrade your dirt bike's valvetrain for maximum flow, heat resistance, and durability with premium valves and parts from JJ Motorsports, precision-engineered for superior performance in motocross, enduro, and trail riding. Our selection includes Black Diamond stainless steel exhaust valves, high-RPM spring kits, keepers, seals, and guides designed for increased lift, reduced wear, and reliable operation under extreme valve float conditions. Compatible with popular 4-stroke models like Honda CRF, Yamaha YZ/WR, KTM SX/EXC, and more, these Kibblewhite components feature one-piece forging, nitride coatings, and dual-spring technology to enhance airflow, prevent valve train failure, and support big-bore or high-compression builds. From exhaust valves with swirl-polished stems to titanium retainer spring kits for lightweight strength, rebuild your cylinder head for championship-level power, longevity, and confidence on every rev.

Shop trusted brands like Kibblewhite for race-proven quality. Explore related categories such as dirt bike piston and ring kits for full top-end rebuilds or dirt bike engine for camshafts and gaskets.

Top Dirt Bike Valve & Parts

  • Kibblewhite Valve - Exhaust - Black Diamond 30-33616 – One-piece Black Diamond stainless steel exhaust valve with nitride coating, swirl-polished stem, and hard tip; designed for high-RPM durability and flow in 4-stroke engines.
  • Kibblewhite Spring Kit 40-41600 – Dual-spring kit with titanium retainers, chromoly seats, and high-strength springs; supports increased lift and RPM while preventing valve float in performance builds.

Browse our in-stock inventory below with same-day shipping and expert support. Free shipping on orders over $99! Questions? Contact us for fitment advice!

  • Product
  • Qty in Cart
  • Quantity
  • Price
  • Subtotal
  • PROX Valve and Spring Kit 28.SES6329-1

    PROX Valve and Spring Kit 28.SES6329-1

    PROX

    $155.95
    If you're running your engine hard, OEM valves and springs will hold you back. The PROX 28.SES6329-1 Kit replaces weak factory components with nitrided steel valves and premium chrome vanadium springs engineered to handle sustained high-RPM abuse without...
    09261430
    SKU:
    09261430
    Availability:
    Ships Same Business Day
    Weight:
    0.24 LBS
    APPLICATION:
    EXHAUST
    TYPE:
    VALVE
    PRODUCT NAME:
    SPRING KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    MATERIAL:
    STEEL
    $155.95
    Qty in Cart: 0
    Quantity:
    Price:
    $155.95
    Subtotal:
  • PROX Valve and Spring Kit 28.SIS1409-2

    PROX Valve and Spring Kit 28.SIS1409-2

    PROX

    $139.95
    High-RPM applications demand valve components that can withstand extreme heat, pressure, and cycling without degradation—stock valves simply won't cut it. The PROX Valve and Spring Kit upgrades your engine with nitrided steel valves and premium chrome...
    09261431
    SKU:
    09261431
    Availability:
    Ships Same Business Day
    Weight:
    0.31 LBS
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    SPRING KIT
    TYPE:
    VALVE
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    Qty in Cart: 0
    Quantity:
    Price:
    $139.95
    Subtotal:
  • PROX Valve and Spring Kit 28.SIS2440-2

    PROX Valve and Spring Kit 28.SIS2440-2

    PROX

    $139.95
    If you're pushing your engine to the limit, your OEM valves and springs won't keep pace. The PROX 28.SIS2440-2 Kit replaces worn or inadequate factory components with nitrided steel valves and premium chrome vanadium springs engineered to handle extreme...
    09261432
    SKU:
    09261432
    Availability:
    Ships Same Business Day
    Weight:
    0.34 LBS
    PRODUCT NAME:
    SPRING KIT
    TYPE:
    VALVE
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    Qty in Cart: 0
    Quantity:
    Price:
    $139.95
    Subtotal:
  • PROX Valve and Spring Kit 28.SIS6327-2

    PROX Valve and Spring Kit 28.SIS6327-2

    PROX

    $149.95
    If you're running high-RPM applications or building a race engine, OEM valve assemblies won't cut it. The PROX Valve and Spring Kit 28.SIS6327-2 replaces stock valves and springs with nitrided steel construction and premium chrome vanadium springs...
    09261435
    SKU:
    09261435
    Availability:
    Ships Same Business Day
    Weight:
    0.27 LBS
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    APPLICATION:
    INTAKE
    PRODUCT NAME:
    SPRING KIT
    TYPE:
    VALVE
    Qty in Cart: 0
    Quantity:
    Price:
    $149.95
    Subtotal:
  • PROX Intake Valve and Spring Kit 28.SIS1340-2

    PROX Intake Valve and Spring Kit 28.SIS1340-2

    PROX

    $155.95
    If you're running higher RPMs or pushing your engine beyond stock parameters, OEM valve springs will eventually lose their ability to control valve timing under load—leading to float, missed shifts, and catastrophic engine damage. The PROX Intake Valve...
    09262892
    SKU:
    09262892
    Availability:
    Ships Same Business Day
    Weight:
    0.30 LBS
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    PRODUCT NAME:
    VALVE AND SPRING KIT
    Qty in Cart: 0
    Quantity:
    Price:
    $155.95
    Subtotal:
  • PROX Valve and Spring Kit 28.SES2414-1

    PROX Valve and Spring Kit 28.SES2414-1

    PROX

    $155.95
    If you're pushing your engine to its limits, factory valve and spring assemblies become a liability. The PROX 28.SES2414-1 kit replaces worn OEM components with nitrided steel valves and premium chrome vanadium springs engineered to withstand sustained...
    09262724
    SKU:
    09262724
    Availability:
    Ships Same Business Day
    Weight:
    0.25 LBS
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    VALVE AND SPRING KIT
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    VALVE
    UNITS:
    KIT
    Qty in Cart: 0
    Quantity:
    Price:
    $155.95
    Subtotal:
  • PROX Valve and Spring Kit 28.SES2444-1

    PROX Valve and Spring Kit 28.SES2444-1

    PROX

    $159.95
    If you're running your engine at sustained high RPM or pushing it beyond stock parameters, OEM valve springs will eventually lose their snap—and valve float becomes a real problem. The PROX Valve and Spring Kit 28.SES2444-1 pairs durable nitrided steel...
    09262725
    SKU:
    09262725
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    SPRING KIT
    UNITS:
    KIT
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    VALVE
    Qty in Cart: 0
    Quantity:
    Price:
    $159.95
    Subtotal:
  • PROX Valve and Spring Kit 28.SIS2414-2

    PROX Valve and Spring Kit 28.SIS2414-2

    PROX

    $155.95
    If you're pushing your engine to its limits, OEM valves and springs won't cut it. The PROX 28.SIS2414-2 Kit replaces those weak factory components with nitrided steel valves and premium chrome vanadium springs engineered to handle extreme RPM and...
    09262728
    SKU:
    09262728
    Availability:
    Ships Same Business Day
    Weight:
    0.25 LBS
    APPLICATION:
    INTAKE
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    VALVE
    PRODUCT NAME:
    VALVE AND SPRING KIT
    UNITS:
    KIT
    Qty in Cart: 0
    Quantity:
    Price:
    $155.95
    Subtotal:
  • PROX Valve and Spring Kit 28.SIS2444-2

    PROX Valve and Spring Kit 28.SIS2444-2

    PROX

    $166.95
    If you're running high-RPM applications or pushing your engine beyond stock parameters, OEM valve springs will struggle to keep pace with valve float and premature wear. The PROX Valve and Spring Kit 28.SIS2444-2 replaces both intake and exhaust valves...
    09262729
    SKU:
    09262729
    Availability:
    Ships Same Business Day
    Weight:
    0.25 LBS
    APPLICATION:
    INTAKE
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    VALVE
    PRODUCT NAME:
    VALVE AND SPRING KIT
    UNITS:
    KIT
    $166.95
    Qty in Cart: 0
    Quantity:
    Price:
    $166.95
    Subtotal:
  • PROX Exhaust Valve 28.1334-1

    PROX Exhaust Valve 28.1334-1

    PROX

    $40.95
    Proper valve operation is critical to engine reliability and performance—a compromised exhaust valve leads to lost compression, increased emissions, and potential catastrophic engine damage. The PROX 28.1334-1 is engineered to OEM specifications,...
    09260143
    SKU:
    09260143
    Availability:
    Ships Same Business Day
    Weight:
    0.08 LBS
    PRODUCT NAME:
    VALVE
    UNITS:
    EACH
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    APPLICATION:
    EXHAUST
    $40.95
    Qty in Cart: 0
    Quantity:
    Price:
    $40.95
    Subtotal:
  • PROX Exhaust Valve 28.1402-1

    PROX Exhaust Valve 28.1402-1

    PROX

    $40.95
    Proper valve clearance and sealing are critical to engine performance and longevity—a worn or damaged exhaust valve directly impacts compression, combustion efficiency, and power output. The PROX Exhaust Valve 28.1402-1 is engineered to OEM...
    09260144
    SKU:
    09260144
    Availability:
    Ships Same Business Day
    Weight:
    0.08 LBS
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    VALVE
    UNITS:
    EACH
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    $40.95
    Qty in Cart: 0
    Quantity:
    Price:
    $40.95
    Subtotal:
  • PROX Exhaust Valve 28.1495-1

    PROX Exhaust Valve 28.1495-1

    PROX

    $35.95
    A precision exhaust valve is critical to maintaining proper engine breathing and combustion efficiency, directly impacting power output and engine longevity. The PROX 28.1495-1 is engineered to OEM specifications, ensuring reliable performance whether...
    09260145
    SKU:
    09260145
    Availability:
    Ships Same Business Day
    Weight:
    0.12 LBS
    RIDING STYLE:
    ATV
    UNITS:
    EACH
    MATERIAL:
    STEEL
    PRODUCT NAME:
    VALVE
    RIDING STYLE:
    OFF-ROAD
    APPLICATION:
    EXHAUST
    $35.95
    Qty in Cart: 0
    Quantity:
    Price:
    $35.95
    Subtotal:
  • PROX Exhaust Valve 28.1654-1

    PROX Exhaust Valve 28.1654-1

    PROX

    $56.95
    Exhaust valve performance directly impacts engine efficiency, combustion temperature management, and overall power delivery. The PROX 28.1654-1 is precision-engineered to OEM specifications, ensuring reliable sealing and consistent valve timing across...
    09260146
    SKU:
    09260146
    Availability:
    Ships Same Business Day
    Weight:
    0.12 LBS
    RIDING STYLE:
    OFF-ROAD
    MATERIAL:
    STEEL
    PRODUCT NAME:
    VALVE
    UNITS:
    EACH
    APPLICATION:
    EXHAUST
    $56.95
    Qty in Cart: 0
    Quantity:
    Price:
    $56.95
    Subtotal:
  • PROX Exhaust Valve 28.3402-1

    PROX Exhaust Valve 28.3402-1

    PROX

    $35.95
    A worn or damaged exhaust valve compromises engine breathing, power delivery, and fuel efficiency—forcing your engine to work harder for less performance. The PROX Exhaust Valve 28.3402-1 restores proper valve sealing and thermal management, ensuring...
    09260147
    SKU:
    09260147
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    RIDING STYLE:
    ATV
    UNITS:
    EACH
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    VALVE
    $35.95
    Qty in Cart: 0
    Quantity:
    Price:
    $35.95
    Subtotal:
  • PROX Exhaust Valve 28.2418-1

    PROX Exhaust Valve 28.2418-1

    PROX

    $29.95
    Exhaust valves are critical to engine breathing and combustion efficiency—a worn or substandard valve directly compromises horsepower, fuel economy, and engine longevity. The PROX 28.2418-1 is precision-manufactured to OEM specifications, ensuring...
    09260148
    SKU:
    09260148
    Availability:
    Ships Same Business Day
    Weight:
    0.08 LBS
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    APPLICATION:
    EXHAUST
    PRODUCT NAME:
    VALVE
    $29.95
    Qty in Cart: 0
    Quantity:
    Price:
    $29.95
    Subtotal:
  • PROX Intake Valve 28.1495-2

    PROX Intake Valve 28.1495-2

    PROX

    $25.95
    Precision valve operation is critical to engine reliability and performance—any deviation in valve geometry directly impacts combustion efficiency and durability. The PROX Intake Valve 28.1495-2 is engineered to exact OEM specifications, ensuring your...
    09260149
    SKU:
    09260149
    Availability:
    Ships Same Business Day
    Weight:
    0.12 LBS
    APPLICATION:
    INTAKE
    MATERIAL:
    STEEL
    PRODUCT NAME:
    VALVE
    RIDING STYLE:
    ATV
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    $25.95
    Qty in Cart: 0
    Quantity:
    Price:
    $25.95
    Subtotal:
  • PROX Intake Valve 28.1654-2

    PROX Intake Valve 28.1654-2

    PROX

    $35.95
    A properly functioning intake valve is critical to your engine's breathing efficiency and power delivery. The PROX 28.1654-2 is precision-manufactured to OEM specifications, ensuring reliable sealing and consistent performance under demanding conditions...
    09260150
    SKU:
    09260150
    Availability:
    Ships Same Business Day
    Weight:
    0.12 LBS
    APPLICATION:
    INTAKE
    MATERIAL:
    STEEL
    PRODUCT NAME:
    VALVE
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    $35.95
    Qty in Cart: 0
    Quantity:
    Price:
    $35.95
    Subtotal:
  • PROX Intake Valve 28.3402-2

    PROX Intake Valve 28.3402-2

    PROX

    $30.95
    A worn or damaged intake valve directly compromises cylinder sealing, fuel efficiency, and combustion reliability—issues that cascade into poor engine performance and increased wear on surrounding components. The PROX 28.3402-2 is engineered to OEM...
    09260151
    SKU:
    09260151
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    APPLICATION:
    INTAKE
    MATERIAL:
    STEEL
    PRODUCT NAME:
    VALVE
    RIDING STYLE:
    ATV
    UNITS:
    EACH
    RIDING STYLE:
    OFF-ROAD
    $30.95
    Qty in Cart: 0
    Quantity:
    Price:
    $30.95
    Subtotal:
  • PROX Intake Valve 28.2418-3

    PROX Intake Valve 28.2418-3

    PROX

    $22.95
    Precision intake valve operation is critical to engine efficiency and reliability—especially under high-performance conditions where tolerances matter. The PROX 28.2418-3 is manufactured to exacting OEM specifications, ensuring consistent sealing, proper...
    09260153
    SKU:
    09260153
    Availability:
    Ships Same Business Day
    Weight:
    0.08 LBS
    APPLICATION:
    INTAKE
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    EACH
    PRODUCT NAME:
    VALVE
    $22.95
    Qty in Cart: 0
    Quantity:
    Price:
    $22.95
    Subtotal:
  • PROX Valve Shims - 5 pack 29.748120

    PROX Valve Shims - 5 pack 29.748120

    PROX

    $10.95
    Valve shim wear directly impacts your engine's valve clearance and overall performance consistency—especially under high-RPM conditions where precision matters most. PROX Valve Shims deliver OEM-equivalent durability at a fraction of the cost, making...
    09260870
    SKU:
    09260870
    Availability:
    Ships Same Business Day
    Weight:
    0.01 LBS
    OUTSIDE DIAMETER METRIC:
    7.48 MM
    RIDING STYLE:
    STREET
    PRODUCT NAME:
    SHIM KIT
    RIDING STYLE:
    SNOW
    RIDING STYLE:
    UTV
    RIDING STYLE:
    WATERCRAFT
    UNITS:
    5 PACK
    VALVE SHIM THICKNESS METRIC:
    1.20 MM
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    ATV
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    VALVE
    $10.95
    Qty in Cart: 0
    Quantity:
    Price:
    $10.95
    Subtotal:
  • Total: items /

Adding your products to cart

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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