Mikuni Main Jet - N100.604

The Mikuni N100.604 is a genuine large-round main jet supplied as a new, parts-only carburetor component, designed to deliver precise fuel metering for optimal engine performance. Featuring an 8 mm head, this large-round series jet is engineered for compatibility across a broad range of Mikuni carburetor families, including VM, TM, HS/HSR, RS, BST, and BS models, making it a versatile choice for classic and modern motorcycle, ATV, and small-engine applications.

Precision-machined to Mikuni's exacting factory tolerances, the N100.604 ensures consistent fuel flow and reliable throttle response, helping maintain smooth performance whether you're fine-tuning a stock setup or dialing in a custom carburetor build. Each jet is stamped with a size designation on the head and bears the distinctive Mikuni square-within-a-square manufacturer's mark, allowing for easy visual verification of authenticity and specification before installation.

Because jet sizing can vary subtly between carburetor series and model years, it's essential to select the correct size variant for your application and physically compare it against your existing jet before ordering. This large-round body design is identifiable by its dimensional profile, distinct from other Mikuni jet series, so careful measurement against your removed original jet remains the most reliable way to confirm fitment.

• Genuine Mikuni new parts-only main jet

• Large-round series with 8 mm head diameter

• Compatible with VM, TM, HS/HSR, RS, BST, and BS carburetor families

• Identified by Mikuni square-within-a-square mark and head size stamping

• Precision fuel metering for consistent engine performance

• Multiple size variants available — physical comparison recommended before purchase