YS Engine YSR6202 Sub Needle Valve 61H replacement part for RC carburettors  [YSR6202]

Sub needle valve role and fit

This YS Engine YSR6202 Sub Needle Valve 61H is an RC-scale replacement part intended for use in glow-fuel model engine carburettors. It is the needle element that meters fuel flow through the carburettor, allowing finer adjustment of idle and part-throttle behaviour during tuning.

The part is described as a sub needle valve type and should be treated as a consumable spare for routine maintenance or tuning sessions. When diagnosing rich or lean conditions, swapping the sub needle valve can confirm whether wear or contamination in the needle assembly is affecting fuel metering.

Installation notes: access the carburettor per your engine service procedure, remove the old sub needle assembly carefully to avoid debris entering the carburettor throat, and seat the replacement needle with the same orientation and clearances used by the original. Make small incremental adjustments and verify engine response on the ground before full-power runs.

Maintenance and tuning role: the sub needle valve affects mid-range and idle fuel delivery, so use it together with main needle and idle settings when refining throttle response; keep the area clean and inspect the needle tip for wear or contamination during regular service.