YS Engine YSG1046 Replacement Pin for FZ70S Disc Valve  [YSG1046]

Description of the FZ70S disc valve pin

The disc valve pin is supplied as a replacement part for disc valve assemblies carrying the FZ70S identifier. Its role is to locate and retain the disc valve assembly while preserving correct alignment during engine operation.

Function and compatibility: Matched to the FZ70S disc valve layout, the pin assists in keeping the valve disc seated and aligned so that throttle characteristics and engine breathing remain consistent. It is intended as a service spare and does not alter power output on its own.

Fitting instructions: Remove the necessary access covers on the engine to reach the disc valve, carefully extract the existing pin to avoid damaging the disc or the housing, and press in the replacement using steady pressure so it seats properly. Use appropriate basic tools and ensure sealing surfaces are clean before reassembly.

Service guidance: Replacing a bent or worn pin should be part of scheduled checks; a correctly seated locating pin helps maintain repeatable valve timing and reduces the risk of erratic throttle response. Inspect the valve faces and verify free disc movement after refit.