YS Engine YSS8132 61ST-2 Low Speed Needle Valve for RC Carburettor  [YSS8132]

Low-speed carburettor needle overview

This is a replacement low-speed needle intended for use with YS Engine carburettor assemblies. It performs the low-throttle mixture adjustment task, allowing setting of idle mixture and smoothing engine behaviour at light throttle; the notes below concentrate on fitment checks, service handling, and tuning role without adding extra spec claims.

Compatibility note: the title identifies this as a YS Engine low speed needle designed for YS Engine carburettor assemblies. No claim is made for fitment with other manufacturers.

Installation and handling:

• Remove any air filter or cover to access the low-speed needle entry point.
• Unscrew the fitted needle carefully while noting the original seating or counting turns to preserve the baseline reference.
• Fit the replacement needle with the same orientation, return it to the factory baseline, and verify free throttle movement without binding.
• Carry out a controlled run-in after installation and adjust the needle in small steps while observing idle and low-throttle response.

Tuning role:

• The low-speed needle governs fuel mixture at idle and at small throttle openings, influencing smoothness and throttle transition behavior.
• Use modest adjustments and short test runs to prevent overly lean or rich conditions; always start from the original baseline.
• Replace the needle when wear, damage, or contamination impairs mixture control at low throttle settings.