Mikuni Jet Needle Richest - HSR42 Carburetor
About Mikuni
Mikuni has supplied carburetors and fuel-system components to the motorcycle industry for decades, and its HSR series remains a common choice for carbureted Evolution and Twin Cam V-twins where a clean, tunable fuel curve matters more than electronics.
When dialing in your Mikuni HSR42 carburetor, the jet needle plays a critical role in mid-range fuel delivery. This Mikuni jet needle is calibrated to the richest setting, allowing you to fine-tune your V-twin's fuel mixture for optimal performance.
Why riders pick this
- Richest calibration for HSR42 carburetors
- Optimizes mid-range throttle response
- Genuine Mikuni OEM replacement part
- Crucial for precise V-twin carb tuning
A properly jetted carburetor ensures your Harley or Indian V-twin runs strong across the entire RPM range. This genuine Mikuni jet needle for the HSR42 carburetor provides the richest possible fuel setting for the mid-range throttle, an essential component for achieving precise fuel metering as you roll through the gears.
Optimize Your Fuel Curve
- Richest available calibration for HSR42 carburetors
- Direct OEM Mikuni replacement for reliable performance
- Essential component for precise mid-range fuel delivery
- Helps eliminate lean conditions at partial throttle openings
Tuning for V-Twin Performance
Changing your jet needle is a common and effective tuning step for HSR42-equipped V-twins, especially after exhaust or air cleaner upgrades. This richest needle helps ensure your engine gets the fuel it needs, preventing potential damage from running too lean and unlocking more usable power. Always confirm your specific tuning needs with a qualified mechanic or dyno tuner for best results.
Specifications
- Brand: Mikuni
- Manufacturer Part #: FJ8-8DDY01-95
- Length: 4.7 in
- Width: 2.7 in
- Height: 0.4 in
- Weight: 0.05 lbs
- Country of Origin: Japan
Common questions
What Mikuni carburetor does this jet needle fit?
This jet needle is specifically designed for Mikuni HSR42 carburetors. Please verify your carburetor model before ordering.
Is this the richest jet needle available for the HSR42?
Yes, this particular jet needle offers the richest calibration setting for the Mikuni HSR42 carburetor. Leaner options are available if needed for your specific setup.
Will installing this jet needle require a full carburetor tune?
Changing the jet needle primarily affects fuel delivery in the mid-range. Depending on your current setup and other modifications, a full carburetor tune-up or dyno session may be recommended to achieve the best overall performance and fuel mixture.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | Mikuni |
| TYPE | Intake/Carb/Fuel System |
| SKU | 14-2504 |
| WEIGHT | 0.05 lb |
