Throttle Rotor Replacement OS40981200 for RC Carburettors by O.S. Engine  [OS40981200]

Throttle rotor replacement for RC carburettors

This part is an RC-scale carburettor rotor intended to replace the rotating throttle element and recover consistent throttle feel and mechanical fit within compatible carburettor bodies. Worn or damaged rotors commonly produce uneven throttle response and unstable idle, so swapping them out is a routine maintenance action.

The installation process is accessible to most hobby technicians: remove the carburettor from the engine, keep track of rotor orientation and any shims or clips, thoroughly clean mating surfaces, and install the new rotor ensuring minimal axial play. Confirm that the rotor moves freely without binding, reassemble, and test throttle return and idle before running.

In tuning work, a well-fitting rotor supports reliable needle tuning and smoother throttle progression. Although the rotor does not adjust mixture directly, replacing it reduces variables so tuning and idle calibration become more consistent.