Throttle Stop Screw YSF1258 for RC Model Engines by YS Engine  [YSF1258]

Adjustable stop to establish a precise idle baseline

The YS Engine YSF1258 throttle stop screw provides a threaded mechanical limit that defines the idle and closed throttle positions on model engine throttles. By setting this stop you gain a predictable physical endpoint that helps steady idle and prevent unintended full closure.

Fitted as a direct replacement for factory stop screws where a threaded limiter is accepted, the part supplies a reliable contact interface for throttle arms. It is purely mechanical, so it complements rather than replaces electronic endpoint adjustments.

To install, remove the original stop screw and thread the YSF1258 into place until it lightly touches the throttle arm at the targeted idle. Make small incremental turns and bench-test the engine to confirm the desired idle and responsiveness. Take care to avoid abrupt throttle changes during adjustment.

Tuning tip: use this stop to lock in a dependable idle before changing needle positions or electronic throttle endpoints on servo-controlled rigs. The screw is a simple, repeatable tool for achieving consistent throttle behavior during setup and events.