YS Engine YSR6202 Sub Needle Valve 61H Replacement Part for RC Carburettors  [YSR6202]

Function and suitability of the sub needle

This YS Engine YSR6202 Sub Needle Valve 61H is a replacement needle intended for use in glow-fuel model engine carburettors. The needle meters fuel through the carburettor and permits finer control of idle and part-throttle behaviour during tuning.

The item is a sub needle valve type and should be regarded as a consumable spare for regular maintenance or tuning work. Swapping the sub needle during diagnosis can reveal whether wear or contamination in the needle assembly is causing rich or lean running.

Installation notes: follow your engine's service procedure to access the carburettor, remove the old sub needle carefully to avoid letting debris into the throat, and install the new needle with the same orientation and clearances as the original. Make small, incremental adjustments and confirm engine response on the ground before full-power runs.

Maintenance and tuning role: the sub needle affects mid-range and idle delivery, so adjust it alongside the main needle and idle settings when refining throttle response; keep the area clean and inspect the needle tip for wear or contamination during servicing.