YS Engine YSE1275 DZ170 CDI Sub Needle O-Ring  [YSE1275]

DZ170 CDI Sub Needle O-Ring Details

This YS Engine sub needle O-ring is an RC-scale spare designed to recover the sealing function around the sub needle area of DZ170 CDI engines. It replaces the small O-ring in the needle assembly to help preserve consistent needle behaviour when adjusting throttle and idle.

Compatibility is limited to the DZ170 CDI designation shown above. Do not assume interchangeability with other engine models without measuring the needle and seat geometry. The item is supplied as an individual replacement component, not as a full maintenance kit.

Installation is suitable for general hobby maintenance: remove the needle assembly, check the needle seat and bore for contamination or wear, fit the replacement O-ring, then reassemble and confirm smooth needle movement. After fitting, perform gradual carburettor adjustments and bench tests before extended running to verify tuning.

Use the O-ring primarily as a preventative or restorative maintenance item; it maintains seal integrity for steady idle and mid-throttle tuning but will not by itself change main jet settings or needle profile effects.