YS Engine YSG1045 Disc Valve Spare for FZ70S  [YSG1045]

Disc-valve fitment for FZ70S engines

The YS Engine YSG1045 disc valve serves as an aftermarket replacement for the FZ70S range of two-stroke model powerplants. It replaces the intake timing disc to restore sealing and correct timing where the original component shows wear.

Fitting is performed on the bench: remove the intake cover, extract the worn disc assembly, inspect the mating surfaces and replace with the new unit. Ensure the disc runs true and maintains the correct clearance relative to the crankcase port before final assembly and running.

For tuning purposes the disc influences intake timing and throttle transient response; replacing a worn disc helps return consistent acceleration characteristics. Regular checks for deformation, scoring, and seal condition are advised to keep the engine performing reliably.