O.S. Engine OS40981200 Carburetor Rotor 60PA FSa-95V, carburettor rotor for RC carburettor assemblies  [OS40981200]

Carburetor rotor for RC models

This rotor is an RC-scale carburettor replacement part intended to restore consistent throttle response and mechanical fit inside compatible carburettor housings. It serves as the rotating throttle element that interfaces with the carburettor body, and when worn or damaged it can cause uneven throttle feel and idle instability. Replacing the rotor is a standard maintenance task to regain smooth control response.

Installation is straightforward for hobby technicians: remove the carburettor from the engine, note the rotor orientation and supporting shims or clips, clean mating surfaces, and fit the new rotor ensuring minimal axial play. Verify the rotor moves freely through its travel without binding, then reassemble and check throttle linkage return and idle behavior before running.

In tuning and setup, a correctly fitting rotor supports predictable needle adjustment and throttle progression. While the rotor itself is not a tuning part, consistent rotor geometry reduces variables during needle tuning and idle calibration, so technicians often install a new rotor when troubleshooting inconsistent running or when performing a full carburettor service.