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

Needle O-Ring Suitable for DZ170 CDI

This YS Engine sub needle O-ring is provided as a spare to restore the sealing action around the sub needle area of DZ170 CDI engines. It functions as a replacement O-ring for the needle assembly to help keep needle response stable during throttle and idle adjustments.

The stated compatibility applies specifically to the DZ170 CDI designation used in the product title. Do not presume fit on other engine lines without checking needle and seat dimensions. The item is offered as a single replacement piece rather than a service kit.

Fitting is simple for hobbyists: remove the needle assembly, inspect the bore and seat for damage or contamination, install the new O-ring, then reassemble and confirm smooth needle travel. After fitting, make incremental carburettor adjustments and carry out bench checks before extended running to ensure correct tuning behavior.

Consider the O-ring a maintenance component that preserves needle seal integrity; it supports steady idle and mid-throttle settings but will not change main jet or needle-profile characteristics by itself.