Mikuni Large Round Main Jets #120 4-Pack - Harley & Indian V-Twin
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.
Achieve optimal fuel delivery for your carbureted V-twin with this 4-pack of Mikuni #120 large round main jets. These genuine Mikuni components are crucial for precise fuel metering. Riders rely on accurate jetting to compensate for altitude changes, engine modifications, or different fuel types on their Harley-Davidson or Indian Motorcycle.
Why riders pick this
- Genuine Mikuni OEM quality for reliable function
- Precisely meters fuel at cruise and mid-range
- #120 jet size for accurate air-fuel tuning
- Convenient 4-pack for tuning and backup supply
- Fits V-twin carburetors using large round jets
For riders who demand precise control over their V-twin's fuel system, these Mikuni #120 large round main jets are an essential component. Designed to accurately meter fuel at cruise and mid-range throttle positions, they allow you to fine-tune your air-fuel ratio. Whether you're adjusting for performance upgrades like a new exhaust or air cleaner, or simply adapting to varying environmental conditions, this 4-pack provides the flexibility and spares needed for effective carburetor jetting on your Harley or Indian.
Enhanced Carburetor Performance
- Genuine Mikuni OEM part for assured quality
- #120 jet size for targeted fuel calibration
- Large round design fits compatible Mikuni carburetors
- 4-pack quantity for comprehensive tuning and spares
Tuning for Every Ride
Consistent performance from your carbureted V-twin depends heavily on correct jetting. The main jet plays a critical role in how your engine runs at steady throttle. Having a range of jet sizes, or spares of a common size, ensures you can maintain peak efficiency and power. Always consult your motorcycle's service manual or a professional tuner for guidance on the best jetting for your specific engine and riding conditions.
Specifications
- Brand: Mikuni
- Manufacturer Part #: FN100604-120
- Quantity: 4 per pack
- Length: 4.4 in
- Width: 2.2 in
- Height: 0.6 in
- Weight: 0.05 lbs
- Country of Origin: Japan
Common questions
What is the function of a #120 main jet in my V-twin's carburetor?
The #120 main jet controls the fuel flow at cruise and mid-range throttle settings. This precise metering is vital for maintaining an optimal air-fuel ratio, which directly impacts your engine's performance, fuel economy, and overall health.
Will these Mikuni jets fit my Harley-Davidson or Indian Motorcycle with a Mikuni carb?
These large round main jets are designed for V-twin motorcycles equipped with Mikuni carburetors that accept this style. To ensure correct fitment, please verify your specific carburetor model and its current jet requirements using our Shop by Bike tool before purchasing.
Why is it practical to purchase a 4-pack of main jets?
A 4-pack provides ample jets for conducting tuning adjustments, as riders often experiment with different sizes to find the perfect setup. It also ensures you have spare jets on hand for future maintenance or adjustments due to changes in altitude, temperature, or engine modifications.
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 | Jets |
| SKU | 134-7120 |
| WEIGHT | 0.05 lb |
