Jitsie Main Jet Extension Kit Race PWK 28MM Carburettor

• used by factory teams and TrialGP riders
• designed for (Keihin) PWK 28mm carburettors
• improves fuel stability around the main jet
• isolates fuel supply to maintain consistent fuelling
• kit includes:
  • needle jet holder
  • needle jet holder extension
  • CNC machined aluminium float bowl cap with o-ring
• float bowl cap with bonded o-ring for secure sealing
• brass needle jet holder and extension for precision and durability
• requires Jitsie Race main jets (sold separately)
• Race main jets feature a flat-screwdriver slot for installation (T-bar jet tools cannot be used due to compact extension design)

The Jitsie main jet extension kit Race is designed to improve fuel stability around the main jet on (Keihin) PWK 28mm carburettors. In standard setups, increasing float bowl volume can still allow fuel to move away from the main jet under dynamic riding, affecting consistency. This kit addresses that issue by isolating and stabilising the fuel supply directly at the main jet, ensuring reliable fuel availability at all times.

The system consists of a redesigned needle jet holder, a precision extension for the needle jet holder, and a dedicated float bowl cap. Together, these components create a controlled fuel chamber around the main jet, reducing fuel movement and maintaining consistent fuelling in demanding riding conditions.

To work correctly, the kit must be used with Jitsie Race main jets (sold separately). Due to the compact design of the needle jet extension, there is no clearance for a traditional T-bar tool to loosen/tighten the main jet. For this reason, the Race main jets feature a flat-screwdriver slot, allowing easy installation and removal once the extension is fitted.

The float bowl cap is CNC-machined from aluminium and features an integrated O-ring, securely bonded into the sealing groove to prevent fuel leakage. The needle jet holder and extension are manufactured from high-quality brass for precision fitment and long-term durability.