YS Engine 120SR Throttle Barrel Replacement - YSS3021 Throttle Barrel for RC Engines  [YSS3021]

YS 120SR Barrel Overview

This YS Engine YSS3021 throttle barrel is an RC-scale replacement part intended for use with the YS Engine 120SR line. It provides the mechanical connection between the carburettor throttle shaft and the throttle linkage, delivering direct, predictable throttle input for small model engines.

As a spare part, its purpose is purely mechanical: maintain smooth rotation, correct linkage alignment, and consistent throttle travel. Inspect the mating surfaces for scoring or wear when fitting a new barrel and confirm the throttle returns cleanly to idle with no binding throughout the travel.

During installation, check fit and alignment within the carburettor housing and on the throttle arm. Small changes to linkage geometry or stop positions may be needed to recover the original idle and full-throttle positions; cycle the throttle through its entire range before running the engine. Regular inspection as part of maintenance helps catch excessive wear that can degrade throttle response.