FS Engine Rocker Support OS45261410 for FS-40S, FS-48S, FS-52S by O.S. Engine  [OS45261410]

Designed for the O.S. Engine FS carbureted lineup, this rocker support fits FS-40S, FS-48S and FS-52S engines and stabilises the rocker train during tuning work. It serves as the locating and bearing point for the rocker assembly and helps preserve intended valve geometry under load.

To install, remove the cylinder head and rocker assembly, inspect the rocker shaft and bearings for wear, replace the support in the original orientation and secure using the existing fasteners. Recheck valve clearances and make fine shim adjustments to achieve the desired valve lift and timing.

From a tuning perspective the support contributes to repeatable valve motion and steadier idle and throttle response. Replacing a worn support can reduce run-to-run variation and make tuning outcomes more predictable.