YS Engine YSS3021 Throttle Barrel for 120SR – Precision Throttle Replacement  [YSS3021]

Throttle Barrel Compatible with YS 120SR

This YS Engine YSS3021 throttle barrel is intended as a replacement part for the YS Engine 120SR series. It serves as the direct mechanical link between the carburettor throttle shaft and the external throttle linkage, ensuring accurate transmission of throttle commands on small model engines.

The barrel's role is simple but critical: allow smooth rotation, keep linkage alignment true, and deliver repeatable throttle motion. When fitting a new barrel inspect the bore and shaft interfaces for wear and confirm the throttle returns cleanly to idle without any binding across the full travel range.

During installation, ensure the barrel seats correctly in the carburettor housing and the throttle arm lines up with the linkage. You may need to fine-tune linkage geometry or adjust stop positions to recover the correct idle and full-throttle settings; always test the entire throttle sweep before running the engine. Routine visual checks will catch progressive wear before it impacts performance.