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
-
On Sale
PROX Exhaust Valve 28.1227-1
PROX
MSRP: $30.95Now: $25.00Was: $30.95A precision exhaust valve is critical to maintaining proper combustion chamber sealing and engine performance under high RPM and sustained heat cycles. OEM-specification exhaust valves like the PROX 28.1227-1 ensure your engine breathes efficiently while...09260668- SKU:
- 09260668
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- UNITS:
- EACH
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- VALVE
MSRP: $30.95Now: $25.00Was: $30.95 -
On Sale
PROX Exhaust Valve 28.1407-1
PROX
MSRP: $44.95Now: $38.00Was: $44.95A precision exhaust valve is critical to your engine's breathing efficiency and longevity. The PROX 28.1407-1 delivers OEM-specification performance with tight tolerances and premium construction, ensuring reliable operation under sustained high-RPM...09260677- SKU:
- 09260677
- Availability:
- Ships Same Business Day
- Weight:
- 0.09 LBS
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- VALVE
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
MSRP: $44.95Now: $38.00Was: $44.95Qty in Cart: 0Quantity:Price:MSRP: $44.95Now: $38.00Was: $44.95Subtotal: -
PROX Intake Valve and Spring Kit 28.SIS3338-2
PROX
$155.95If you're pushing your engine to the limit, OEM valve springs will eventually let you down—they simply aren't engineered for sustained high-RPM loads. The PROX Intake Valve and Spring Kit 28.SIS3338-2 replaces those weak links with nitrided steel valves...09261461- SKU:
- 09261461
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- SPRING KIT
- TYPE:
- VALVE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- TI-STEEL
$155.95 -
PROX Valve and Spring Kit 28.SIS4341-2
PROX
$155.95If you're running your engine hard at high RPM, OEM valve and spring components become a limiting factor—they simply weren't engineered to handle sustained extreme conditions. The PROX 28.SIS4341-2 Kit replaces those weak points with purpose-built steel...09261465- SKU:
- 09261465
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- SPRING KIT
- TYPE:
- VALVE
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$155.95 -
PROX Valve and Spring Kit 28.SES6351-1
PROX
$149.95If you're pushing your engine to the limit, factory valve components simply won't cut it. The PROX Valve and Spring Kit 28.SES6351-1 replaces worn OEM valves and springs with nitrided steel valves and premium chrome vanadium springs engineered to handle...09262726- SKU:
- 09262726
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- SPRING KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- STEEL
- TYPE:
- VALVE
$149.95Qty in Cart: 0Quantity:Price:$149.95Subtotal: -
PROX Valve and Spring Kit 28.SES6353-1
PROX
$149.95If you're pushing your engine beyond stock limits, OEM valves and springs will become your bottleneck. The PROX 28.SES6353-1 Kit replaces those weak points with nitrided steel valves and premium chrome vanadium springs engineered to handle sustained...09262727- SKU:
- 09262727
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
- UNITS:
- KIT
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- SPRING KIT
$149.95Qty in Cart: 0Quantity:Price:$149.95Subtotal: -
PROX Valve and Spring Kit 28.SIS6351-2
PROX
$149.95If you're pushing your engine to its limits, OEM valves and springs will hold you back. The PROX 28.SIS6351-2 Kit replaces factory components with nitrided steel valves and premium chrome vanadium springs engineered to withstand extreme RPM and boost...09262730- SKU:
- 09262730
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- PRODUCT NAME:
- VALVE AND SPRING KIT
- APPLICATION:
- INTAKE
- TYPE:
- VALVE
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$149.95Qty in Cart: 0Quantity:Price:$149.95Subtotal: -
PROX Valve and Spring Kit 28.SIS6353-2
PROX
$149.95If you're running high RPM or pushing your engine beyond stock parameters, OEM valves and springs become the weak link in your valve train. The PROX 28.SIS6353-2 Kit replaces them with nitrided steel valves and premium chrome vanadium springs engineered...09262731- SKU:
- 09262731
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- APPLICATION:
- INTAKE
- MATERIAL:
- STEEL
- TYPE:
- VALVE
- PRODUCT NAME:
- VALVE AND SPRING KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$149.95Qty in Cart: 0Quantity:Price:$149.95Subtotal: -
PROX Valve Shims - 5 pack 29.748130
PROX
$9.95Valve shim wear is one of the most overlooked maintenance items that directly impacts engine performance and longevity. PROX Valve Shims deliver precision-machined replacement solutions at a fraction of OEM costs, allowing you to maintain proper valve...09260872- SKU:
- 09260872
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- UNITS:
- 5 PACK
- RIDING STYLE:
- STREET
- RIDING STYLE:
- WATERCRAFT
- VALVE SHIM THICKNESS METRIC:
- 1.30 MM
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shims - 5 pack 29.748200
PROX
$9.95Valve shim wear is a silent killer of engine efficiency—when your shims degrade, you lose precise valve timing and risk costly damage to your head. PROX Valve Shims deliver OEM-level performance at a fraction of the replacement cost, with heat-treated...09260886- SKU:
- 09260886
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- STREET
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- VALVE SHIM THICKNESS METRIC:
- 2.00 MM
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- TYPE:
- VALVE
- UNITS:
- 5 PACK
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- WATERCRAFT
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shims - 5 pack 29.748255
PROX
$9.95Valve shim replacement is inevitable maintenance for high-revving engines, and OEM options can drain your budget fast. PROX Valve Shims deliver precision-engineered durability at a fraction of OEM cost, with proprietary heat-treatment that resists wear...09260897- SKU:
- 09260897
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
- RIDING STYLE:
- STREET
- RIDING STYLE:
- WATERCRAFT
- VALVE SHIM THICKNESS METRIC:
- 2.55 MM
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- UNITS:
- 5 PACK
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shims - 5 pack 29.748300
PROX
$10.95Valve shim wear directly impacts your engine's valve clearance, compression, and overall performance consistency—especially under high-RPM conditions. PROX Valve Shims deliver precision-machined replacements at a fraction of OEM cost, allowing you to...09260906- SKU:
- 09260906
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- STREET
- RIDING STYLE:
- UTV
- VALVE SHIM THICKNESS METRIC:
- 3.00 MM
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
$10.95 -
PROX Valve Shims - 5 pack 29.748305
PROX
$9.95Valve shim wear directly impacts cylinder head performance and engine reliability—these precision-machined shims maintain exact valve clearances without the cost of OEM replacements. PROX shims are heat-treated to maximize hardness and durability,...09260907- SKU:
- 09260907
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- VALVE SHIM THICKNESS METRIC:
- 3.05 MM
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- STREET
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shims - 5 pack 29.748315
PROX
$9.95Valve shim wear directly impacts engine timing and performance—especially in high-RPM applications where tolerances are critical. PROX Valve Shims deliver precision replacements that restore proper valve clearance without the expense of OEM alternatives...09260909- SKU:
- 09260909
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- STREET
- VALVE SHIM THICKNESS METRIC:
- 3.15 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- TYPE:
- VALVE
- UNITS:
- 5 PACK
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- WATERCRAFT
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shim - 5 pack 29.948120
PROX
$9.95Valve shim selection directly impacts your engine's valvetrain precision and longevity. PROX Valve Shims are heat-treated to maintain hardness under extreme operating conditions, reducing wear and maintaining exact clearances across extended engine life...09260942- SKU:
- 09260942
- Availability:
- Ships Same Business Day
- Weight:
- 0.01 LBS
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- WATERCRAFT
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- TYPE:
- VALVE
- UNITS:
- 5 PACK
- RIDING STYLE:
- STREET
- VALVE SHIM THICKNESS METRIC:
- 1.20 MM
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shim - 5 pack 29.948130
PROX
$9.95Valve shimming is critical for maintaining precise valve clearances, and worn or improperly sized shims will cause lost compression, increased noise, and accelerated wear on your valve train. The PROX Valve Shim 5-pack delivers OEM-equivalent precision...09260944- SKU:
- 09260944
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- UNITS:
- 5 PACK
- RIDING STYLE:
- STREET
- RIDING STYLE:
- WATERCRAFT
- VALVE SHIM THICKNESS METRIC:
- 1.30 MM
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shim - 5 pack 29.948135
PROX
$9.95Valve shims are critical components in high-performance engine builds, directly affecting valve clearance, lift characteristics, and overall engine responsiveness. PROX valve shims are precision-machined to exact tolerances and heat-treated for superior...09260945- SKU:
- 09260945
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- STREET
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- VALVE SHIM THICKNESS METRIC:
- 1.35 MM
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- TYPE:
- VALVE
- UNITS:
- 5 PACK
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- WATERCRAFT
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shim - 5 pack 29.948150
PROX
$10.95Valve shim adjustments are critical to maintaining proper valve clearance and preventing catastrophic engine damage—this 5-pack ensures you have spares on hand for tuning or replacement. PROX valve shims are precision-engineered to exact tolerances,...09260948- SKU:
- 09260948
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- TYPE:
- VALVE
- UNITS:
- 5 PACK
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- VALVE SHIM THICKNESS METRIC:
- 1.50 MM
- RIDING STYLE:
- WATERCRAFT
$10.95Qty in Cart: 0Quantity:Price:$10.95Subtotal: -
PROX Valve Shim - 5 pack 29.948280
PROX
$9.95Valve shim clearance directly impacts your engine's performance, reliability, and longevity. PROX Valve Shims are precision-machined to exact tolerances, eliminating guesswork during valve adjustment and ensuring consistent clearance across the entire...09260974- SKU:
- 09260974
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- TYPE:
- VALVE
- VALVE SHIM THICKNESS METRIC:
- 2.80 MM
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- RIDING STYLE:
- STREET
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal: -
PROX Valve Shim - 5 pack 29.948300
PROX
$9.95Valve shims are critical wear items in high-revving engines, and worn or improperly sized shims directly compromise valve clearance and engine efficiency. PROX Valve Shims deliver precision-machined accuracy and heat-treated hardness to maintain exact...09260978- SKU:
- 09260978
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
- OUTSIDE DIAMETER METRIC:
- 9.48 MM
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- WATERCRAFT
- UNITS:
- 5 PACK
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- RIDING STYLE:
- UTV
- VALVE SHIM THICKNESS METRIC:
- 3.00 MM
$9.95Qty in Cart: 0Quantity:Price:$9.95Subtotal:
