Dirt Bike Carburertor Main Jets
Dirt Bike Carburetor Main Jets & Jet Needles for Mikuni Carbs on Honda, Yamaha & KTM at JJ Motorsports
Fine-tune your dirt bike's fuel mixture for optimal power and efficiency with premium carburetor main jets and jet needles from JJ Motorsports. Our selection includes high-precision brass main jets (sizes 100-140) and tapered jet needles designed for consistent mid-range performance, smooth throttle response, and easy tuning in motocross, enduro, and trail riding. Compatible with Mikuni VM series carbs on popular models like Honda CRF, Yamaha YZ/WR, Kawasaki KX, Suzuki RM, and KTM SX/EXC, these Japanese-made components ensure accurate metering, reduced lean spots, and reliable operation in dusty, high-RPM conditions. From 4/042 main jets for VM18/26 carbs to J8-series needles for mid-throttle control, stock up on the parts needed for a full carb rebuild or jetting upgrade.
Shop trusted brands like Mikuni for OEM-quality precision. Explore related categories such as dirt bike carburetor rebuild kits for complete maintenance or dirt bike air and fuel for reeds and filters.
Top Dirt Bike Carburetor Main Jets & Needles
- Mikuni Jet Needle J8-6F08 – Precision tapered jet needle for mid-range fuel control in Mikuni VM series carbs; fits various OE applications, made in Japan for smooth throttle response.
- Mikuni Main Jet #100 - 4-Pack (4/042-100) – Brass main jet pack for VM18, VM24/26, TMX carbs; 6mm diameter, 12mm length, ideal for leaner mixtures in dirt bikes.
- Mikuni Main Jet #125 - 4-Pack (4/042-125) – High-flow brass jets for richer high-RPM tuning; compatible with Mikuni VM series and OE carbs on Honda, Yamaha, and KTM models.
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
-
MIKUNI Needle Valve Arm Spring - 115 grams 730-03027
MIKUNI
$2.84The MIKUNI Needle Valve Arm Spring is a precision replacement component engineered for carburetors that demand reliable fuel metering across varying engine speeds and loads. If your MIKUNI carb is running rich, surging, or exhibiting inconsistent idle...73003027- SKU:
- 73003027
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- SPRING RATE METRIC:
- 115.00 G
- TYPE:
- NEEDLE VALVE
- UNITS:
- EACH
- PRODUCT NAME:
- SPRING
- RIDING STYLE:
- WATERCRAFT
$2.84 -
Wiseco Keihin Main Jet Assortment Kit 135-205 JK001
WISECO
$266.95Carburetor tuning is where precision directly translates to performance gains, and having the right jet selection on hand eliminates guesswork during dyno sessions or track days. The Wiseco Keihin Main Jet Assortment Kit JK001 gives you five jets per...10060314- SKU:
- 10060314
- Availability:
- Ships Same Business Day
- Weight:
- 1.35 LBS
- MATERIAL:
- BRASS
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- ATV
- TYPE:
- KEIHIN
- UNITS:
- KIT
- PRODUCT NAME:
- MAIN JET
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- RIDING STYLE:
- UTV
$266.95 -
Wiseco Mikuni Main Jet Assortment Kit for VM Roundslide/TMX Carbs 160-510 JK003
WISECO
$266.95Carburetor tuning is critical to extracting consistent performance from your engine, and jet selection directly impacts throttle response, fuel delivery, and overall drivability. The Wiseco Mikuni Main Jet Assortment Kit (JK003) eliminates guesswork by...10050166- SKU:
- 10050166
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- MATERIAL:
- BRASS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- MIKUNI
- UNITS:
- KIT
- PRODUCT NAME:
- MAIN JET
- RIDING STYLE:
- STREET
- RIDING STYLE:
- SNOW
$266.95 -
MIKUNI Jet Needle J8-6DJ30
MIKUNI
$10.50Mid-range throttle response is where most carburetors struggle, and a worn or incorrect jet needle compounds the problem with hesitation and flat spots. The MIKUNI J8-6DJ30 restores precise fuel metering in this critical zone, giving you the crisp,...6DJ30- SKU:
- 6DJ30
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- MODEL:
- J8-6DJ30
- PRODUCT NAME:
- JET
- TYPE:
- NEEDLE
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- RIDING STYLE:
- UTV
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- ATV
- UNITS:
- EACH
$10.50 -
MIKUNI Main Jet #125 - 4-Pack 4/042-125
MIKUNI
$14.56Precision fuel metering is the foundation of carburetor tuning, and running the correct main jet size is non-negotiable for consistent performance across throttle positions. This 4-pack of genuine Mikuni #125 main jets gives you the sizing flexibility to...KM4042125- SKU:
- KM4042125
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL DIAMETER METRIC:
- 6.00 MM
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- UTV
- TYPE:
- MAIN
- FEATURES:
- FOR VM CARBURETORS
- PRODUCT NAME:
- JET
- RIDING STYLE:
- STREET
- HEAD TYPE:
- HEX HEAD
- JET SIZE:
- 125
- MATERIAL:
- BRASS
- OVERALL LENGTH:
- 12 MM (0,47')
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- UNITS:
- 4 PACK
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- RIDING STYLE:
- ATV
$14.56 -
MIKUNI Main Jet #130 - 4-Pack 4/042-130
MIKUNI
$14.56Precise fuel metering is non-negotiable when you're tuning a Mikuni carburetor for peak performance. A #130 main jet directly controls fuel flow at mid to high throttle, making it essential for achieving the correct air-fuel ratio on your specific engine...KM4042130- SKU:
- KM4042130
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- BRASS
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- UTV
- TYPE:
- MAIN
- HEAD TYPE:
- HEX HEAD
- JET SIZE:
- 130
- OVERALL DIAMETER METRIC:
- 6.00 MM
- OVERALL LENGTH:
- 12 MM (0,47')
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- UNITS:
- 4 PACK
- FEATURES:
- FOR VM CARBURETORS
- PRODUCT NAME:
- JET
- RIDING STYLE:
- STREET
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- ATV
$14.56 -
MIKUNI Main Jet #135 - 4-Pack 4/042-135
MIKUNI
$14.56Precise jetting is the foundation of carburetor tuning—get it wrong, and you're leaving power on the table or risking lean-condition damage. The MIKUNI Main Jet #135 delivers the exact fuel metering your engine needs across the mid-to-high RPM range,...KM4042135- SKU:
- KM4042135
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- HEAD TYPE:
- HEX HEAD
- OVERALL LENGTH:
- 12 MM (0,47')
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- BRASS
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- TYPE:
- MAIN
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- UTV
- FEATURES:
- FOR VM CARBURETORS
- JET SIZE:
- 135
- OVERALL DIAMETER METRIC:
- 6.00 MM
- PRODUCT NAME:
- JET
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- UNITS:
- 4 PACK
$14.56 -
MIKUNI Main Jet - #140 - 4-Pack N102221-140
MIKUNI
$14.55If you're tuning a CV or Power Jet carburetor, jet selection directly impacts fuel delivery and engine performance across your RPM range. The MIKUNI #140 main jet is engineered for precise fuel metering in mid-to-high throttle conditions, ensuring your...KN102221140- SKU:
- KN102221140
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MODEL:
- MIKUNI
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- STREET
- RIDING STYLE:
- WATERCRAFT
- PRODUCT NAME:
- JET
- RIDING STYLE:
- ATV
- TYPE:
- MAIN
- JET SIZE:
- 140
- MATERIAL:
- BRASS
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- UNITS:
- 4 PACK
$14.55 -
MIKUNI Main Jet #430 - 4-Pack 4/042-430
MIKUNI
$5.20Carburetor tuning is the foundation of reliable performance, and the right main jet is non-negotiable for proper fuel delivery at full throttle. This 4-pack of Mikuni #430 main jets ensures you have spares on hand for testing, backup, or multiple...KM4042430- SKU:
- KM4042430
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- HEAD TYPE:
- HEX HEAD
- MATERIAL:
- BRASS
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- PRODUCT NAME:
- JET
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- TYPE:
- MAIN
- JET SIZE:
- 430
- OVERALL DIAMETER METRIC:
- 6.00 MM
- OVERALL LENGTH:
- 12 MM (0,47')
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- FEATURES:
- FOR VM CARBURETORS
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- SNOW
- UNITS:
- 4 PACK
$5.20 -
MIKUNI Main Jet #440 - 4-Pack 4/042-440
MIKUNI
$5.20If your Mikuni carb is running rich or you're chasing peak performance across the RPM band, jetting is your first lever. The #440 main jet is the direct upgrade path for VM-series and TMX carburetors that shipped with 4/042 specifications—a...KM4042440- SKU:
- KM4042440
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- HEAD TYPE:
- HEX HEAD
- JET SIZE:
- 440
- MATERIAL:
- BRASS
- OVERALL LENGTH:
- 12 MM (0,47')
- RIDING STYLE:
- OFF-ROAD
- FEATURES:
- FOR VM CARBURETORS
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL DIAMETER METRIC:
- 6.00 MM
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- UTV
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- TYPE:
- MAIN
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- OVERALL LENGTH METRIC:
- 12 MM
- PRODUCT NAME:
- JET
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- UNITS:
- 4 PACK
$5.20 -
MIKUNI Main Jet #450 - 4-Pack 4/042-450
MIKUNI
$14.56Proper jetting is foundational to carburetor tuning—too lean and you risk engine damage, too rich and you lose power and efficiency. The MIKUNI #450 main jet delivers precise fuel metering for mid-range and full-throttle performance across a wide range...KM4042450- SKU:
- KM4042450
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- FEATURES:
- FOR VM CARBURETORS
- JET SIZE:
- 450
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- SNOW
- UNITS:
- 4 PACK
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL DIAMETER METRIC:
- 6.00 MM
- OVERALL LENGTH:
- 12 MM (0,47')
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- PRODUCT NAME:
- JET
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- TYPE:
- MAIN
- HEAD TYPE:
- HEX HEAD
- MATERIAL:
- BRASS
$14.56 -
MIKUNI Needle and Seat VM28/163-1.8
MIKUNI
$24.15A worn or damaged needle and seat directly compromises carburetor tuning and fuel delivery consistency—critical factors that separate reliable performance from unpredictable running conditions. This genuine Mikuni assembly restores precise fuel metering,...VM2816318- SKU:
- VM2816318
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
$24.15 -
MIKUNI Needle and Seat VM28/511-1.5
MIKUNI
$24.15The needle and seat assembly is the critical control valve in your carburetor—when it wears, fuel delivery becomes inconsistent, leading to poor idle quality, hesitation, and unpredictable jetting. This genuine Mikuni VM28/511-1.5 assembly restores...VM2851115- SKU:
- VM2851115
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
$24.15 -
MIKUNI Main Jet - #185 - 4-Pack N102221-185
MIKUNI
$14.55If you're tuning a Mikuni carburetor for optimal fuel delivery across your RPM range, the main jet is your primary control—and a worn or incorrect jet directly impacts throttle response, fuel economy, and peak power. The #185 main jet delivers the...KN102221185- SKU:
- KN102221185
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- BRASS
- MODEL:
- MIKUNI
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- WATERCRAFT
- JET SIZE:
- 185
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- TYPE:
- MAIN
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- UNITS:
- 4 PACK
- PRODUCT NAME:
- JET
$14.55 -
MIKUNI Main Jet #410 - 4-Pack 4/042-410
MIKUNI
$5.20Precise jetting is the foundation of carb tuning—get it wrong and you're leaving power on the table or running dangerously lean. These OEM-spec Mikuni #410 main jets give you the exact fuel metering your engine needs for peak performance across the RPM...KM4042410- SKU:
- KM4042410
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL DIAMETER METRIC:
- 6.00 MM
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- UTV
- TYPE:
- MAIN
- HEAD TYPE:
- HEX HEAD
- JET SIZE:
- 410
- MATERIAL:
- BRASS
- OVERALL LENGTH:
- 12 MM (0,47')
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- UNITS:
- 4 PACK
- PRODUCT NAME:
- JET
- RIDING STYLE:
- STREET
- FEATURES:
- FOR VM CARBURETORS
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- ATV
$5.20 -
MIKUNI Main Jet #720 - 4-Pack 4/042-720
MIKUNI
$5.20Fine-tuning your carburetor's fuel delivery is essential for consistent performance, whether you're dialing in a race engine or optimizing a street build. A worn or incorrect main jet directly impacts throttle response, fuel economy, and peak...KM4042720- SKU:
- KM4042720
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL DIAMETER METRIC:
- 6.00 MM
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- UTV
- TYPE:
- MAIN
- PRODUCT NAME:
- JET
- RIDING STYLE:
- STREET
- HEAD TYPE:
- HEX HEAD
- JET SIZE:
- 720
- MATERIAL:
- BRASS
- OVERALL LENGTH:
- 12 MM (0,47')
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- UNITS:
- 4 PACK
- FEATURES:
- FOR VM CARBURETORS
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- RIDING STYLE:
- ATV
$5.20Qty in Cart: 0Quantity:Price:$5.20Subtotal: -
MIKUNI Needle Jet VM34/05-O-4
MIKUNI
$15.49Fine-tuning your carb's midrange response requires precision—and a genuine Mikuni needle jet delivers exactly that. The VM34/05-O-4 gives you direct control over fuel delivery in the critical 1/4 to 3/4 throttle range, where most real-world riding...159O4- SKU:
- 159O4
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- FEATURES:
- FOR VM 30 MM - 36 MM SPIGOT
- PRODUCT NAME:
- JET
- RIDING STYLE:
- ATV
- TYPE:
- NEEDLE
- UNITS:
- EACH
- JET SIZE:
- O-4
- MATERIAL:
- BRASS
- MODEL:
- TYPE 159
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- UTV
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- STREET
$15.49Qty in Cart: 0Quantity:Price:$15.49Subtotal: -
MIKUNI Needle Jet 990-793-004-P-8
MIKUNI
$15.49Fine-tuning your carburetor's mid-range performance requires precision, and the MIKUNI Needle Jet 990-793-004-P-8 delivers exactly that. This genuine Mikuni component directly controls fuel delivery at 1/4 to 3/4 throttle—the range where most real-world...159P8- SKU:
- 159P8
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- FEATURES:
- FOR VM 30 MM - 36 MM SPIGOT
- MATERIAL:
- BRASS
- MODEL:
- TYPE 159
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- JET SIZE:
- P-8
- PRODUCT NAME:
- JET
- RIDING STYLE:
- ATV
- TYPE:
- NEEDLE
- UNITS:
- EACH
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
$15.49 -
MIKUNI Main Jet #175 - 4-Pack 4/042-175
MIKUNI
$14.56Running the wrong main jet size in your Mikuni carb costs you power and driveability—whether you're chasing peak RPM performance or dialing in your street setup. The #175 main jet is the precision tuning solution for mid-to-high speed fuel delivery,...KM4042175- SKU:
- KM4042175
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- HEAD TYPE:
- HEX HEAD
- OVERALL LENGTH:
- 12 MM (0,47')
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- OVERALL DIAMETER:
- 6,00 MM (0,24')
- OVERALL DIAMETER IMPERIAL:
- 0.24'
- OVERALL LENGTH IMPERIAL:
- 0.47'
- RIDING STYLE:
- UTV
- MATERIAL:
- BRASS
- OVERALL LENGTH METRIC:
- 12 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- UNITS:
- 4 PACK
- FEATURES:
- FOR VM CARBURETORS
- JET SIZE:
- 175
- OVERALL DIAMETER METRIC:
- 6.00 MM
- PRODUCT NAME:
- JET
- RIDING STYLE:
- SNOW
- RIDING STYLE:
- STREET
- TYPE:
- MAIN
$14.56 -
MIKUNI Super BN Series Pilot Jet - 4-Pack N100606-675
MIKUNI
$5.20Precise carburetor tuning starts with the right pilot jet, and the MIKUNI Super BN Series delivers the consistency you need for clean idle and smooth low-end response across varying conditions. Whether you're dialing in a vintage race engine or...KN100606675- SKU:
- KN100606675
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- JET SIZE:
- 67.5
- MODEL:
- MIKUNI
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- PILOT
- PRODUCT NAME:
- JET
- UNITS:
- 4 PACK
$5.20
