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
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On Sale
KIBBLEWHITE Valve Guide 30-3030
KIBBLEWHITE
MSRP: $37.93Now: $34.14Was: $37.93Valve guide wear is one of the primary culprits behind oil consumption, reduced compression, and poor ring sealing in high-performance engines. The KIBBLEWHITE Valve Guide 30-3030 delivers the thermal conductivity and wear resistance your engine needs to...KW303030- SKU:
- KW303030
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- INSIDE DIAMETER IMPERIAL:
- 0.2150'
- OUTSIDE DIAMETER IMPERIAL:
- 0.4355'
- PRODUCT NAME:
- VALVE GUIDE
- SIZE IMPERIAL:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- MATERIAL:
- AMPCO-45
- RIDING STYLE:
- ATV
- UNITS:
- EACH
MSRP: $37.93Now: $34.14Was: $37.93 -
On Sale
KIBBLEWHITE Intake Kit 30-31210
KIBBLEWHITE
MSRP: $185.23Now: $166.71Was: $185.23If you're running high-RPM applications or extended engine cycles, OEM intake valves become a wear bottleneck that limits both reliability and performance. The KIBBLEWHITE Black Diamond intake kit replaces those components with stainless steel and...09260443- SKU:
- 09260443
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- RIDING STYLE:
- OFF-ROAD
- SPRING LIFT:
- 0,440'
- SPRING LIFT IMPERIAL:
- 0.440'
- SPRING OPEN PRESSURE:
- 147 LB
- UNITS:
- KIT
- MATERIAL:
- STAINLESS STEEL
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE KIT
- SPRING SEAT PRESSURE:
- 40 LB
- TYPE:
- CONVERSION
MSRP: $185.23Now: $166.71Was: $185.23 -
On Sale
KIBBLEWHITE Valve Guide 40-40320
KIBBLEWHITE
MSRP: $17.83Now: $16.05Was: $17.83Valve guides are critical to maintaining precise valve seating and preventing excessive wear in high-performance engines. The KIBBLEWHITE 40-40320 is engineered with Ampco-45 bronze—a copper-heavy alloy specifically formulated for thermal conductivity...09260449- SKU:
- 09260449
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- EXHAUST
- OUTSIDE DIAMETER IMPERIAL:
- 0.4363'
- PRODUCT NAME:
- VALVE GUIDE
- UNITS:
- EACH
- INSIDE DIAMETER IMPERIAL:
- 0.2150'
- MATERIAL:
- C630 BRONZE
- SIZE IMPERIAL:
- STANDARD
MSRP: $17.83Now: $16.05Was: $17.83 -
On Sale
KIBBLEWHITE Intake Valve 30-3115
KIBBLEWHITE
MSRP: $37.55Now: $33.80Was: $37.55Precision intake valve flow and reliability demand materials that can withstand extreme combustion pressures and thermal cycling without degradation. KIBBLEWHITE's Black Diamond™ valves are engineered from high-strength EV8 stainless steel and finished...KW303115- SKU:
- KW303115
- Availability:
- Ships Same Business Day
- Weight:
- 0.13 LBS
- HEAD DIAMETER METRIC:
- 33.00 MM
- MODEL:
- BLACK DIAMOND™
- STEM DIAMETER IMPERIAL:
- 0.2156'
- LENGTH IMPERIAL:
- 4.040'
- MATERIAL:
- STAINLESS STEEL
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE
- RIDING STYLE:
- OFF-ROAD
- TULIP ANGLE:
- 20°
MSRP: $37.55Now: $33.80Was: $37.55 -
On Sale
KIBBLEWHITE Intake Valve 30-3116
KIBBLEWHITE
MSRP: $37.55Now: $33.80Was: $37.55Intake 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
MSRP: $37.55Now: $33.80Was: $37.55 -
On Sale
KIBBLEWHITE Exhaust Valve Guide 82-82230
KIBBLEWHITE
MSRP: $26.43Now: $23.79Was: $26.43Valve 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
MSRP: $26.43Now: $23.79Was: $26.43 -
On Sale
KIBBLEWHITE Intake Valve 82-82212
KIBBLEWHITE
MSRP: $37.55Now: $33.80Was: $37.55Intake 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'
MSRP: $37.55Now: $33.80Was: $37.55 -
On Sale
KIBBLEWHITE Exhaust Valve 82-82216
KIBBLEWHITE
MSRP: $37.55Now: $33.80Was: $37.55Exhaust 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™
MSRP: $37.55Now: $33.80Was: $37.55 -
On Sale
KIBBLEWHITE Intake/Exhaust Valve Guide 30-4069
KIBBLEWHITE
MSRP: $26.89Now: $24.20Was: $26.89Valve 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
MSRP: $26.89Now: $24.20Was: $26.89 -
On Sale
KIBBLEWHITE Valve Seat 10-SB250
KIBBLEWHITE
MSRP: $30.30Now: $27.27Was: $30.30If 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
MSRP: $30.30Now: $27.27Was: $30.30 -
On Sale
KIBBLEWHITE Valve Seat 10-SB280
KIBBLEWHITE
MSRP: $30.30Now: $27.27Was: $30.30If 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
MSRP: $30.30Now: $27.27Was: $30.30 -
On Sale
KIBBLEWHITE Valve Seat 10-SB350
KIBBLEWHITE
MSRP: $34.71Now: $31.24Was: $34.71If 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
MSRP: $34.71Now: $31.24Was: $34.71 -
On Sale
KIBBLEWHITE Valve Seat 10-SB385
KIBBLEWHITE
MSRP: $40.81Now: $36.73Was: $40.81If 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
MSRP: $40.81Now: $36.73Was: $40.81 -
On Sale
KIBBLEWHITE Valve Seat 10-SB390
KIBBLEWHITE
MSRP: $40.81Now: $36.73Was: $40.81If 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
MSRP: $40.81Now: $36.73Was: $40.81 -
On Sale
KIBBLEWHITE Cast Iron Valve Seat 10-SC290
KIBBLEWHITE
MSRP: $8.24Now: $7.42Was: $8.24If 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
MSRP: $8.24Now: $7.42Was: $8.24 -
On Sale
KIBBLEWHITE Cast Iron Valve Seat 10-SC310
KIBBLEWHITE
MSRP: $8.49Now: $7.64Was: $8.49Valve 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
MSRP: $8.49Now: $7.64Was: $8.49 -
On Sale
KIBBLEWHITE Cast Iron Valve Seat 10-SC390
KIBBLEWHITE
MSRP: $9.57Now: $8.61Was: $9.57Valve 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
MSRP: $9.57Now: $8.61Was: $9.57 -
On Sale
KIBBLEWHITE Spring Kit - .440" 30-31250
KIBBLEWHITE
MSRP: $207.83Now: $187.05Was: $207.83Valve 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
MSRP: $207.83Now: $187.05Was: $207.83 -
On Sale
KIBBLEWHITE Exhaust Valve 30-31266
KIBBLEWHITE
MSRP: $31.01Now: $27.91Was: $31.01Exhaust 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™
MSRP: $31.01Now: $27.91Was: $31.01 -
On Sale
KIBBLEWHITE Exhaust Valve 40-40416
KIBBLEWHITE
MSRP: $31.01Now: $27.91Was: $31.01Exhaust 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
MSRP: $31.01Now: $27.91Was: $31.01
