YS Engine YSS7121 Aluminium Throttle Barrel 61ST-H Spare  [YSS7121]

Throttle sleeve for precise control

The YS Engine YSS7121 throttle barrel serves as a service replacement for YS Engine carburetor assemblies, fitting the throttle slide bore and working with the throttle plate. The description is focused on practical workshop use and neutral technical detail.

The component uses an aluminium-style construction intended to keep the bore geometry stable and the throttle movement consistent. During replacement, remove the carburetor from the model, inspect the slide and linkage for wear or damage, fit the new barrel to the carburetor body, and check that the throttle moves freely through its full travel before reinstalling on the engine. Verify the YSS7121 code against your carburetor casting before ordering.

As part of maintenance and tuning the barrel supports repeatable throttle response and idle behaviour by limiting irregular airflow at part-throttle positions. Use this spare to maintain dependable actuation on glow-engine RC models.