YS Engine YSF1215 Hardened Rocker Arm Shaft for 120 140 160 RC engines  [YSF1215]

Valve pivot shaft for 120/140/160 glow engines

This replacement rocker arm shaft is an RC-scale valve train component designed for use with YS Engine models identified by 120, 140 and 160 in the product name. It serves as the pivot axis for rocker arms, transferring cam motion to the valve mechanism and maintaining alignment under throttle and idle conditions.

Installation notes: remove the cylinder head and rocker assembly following your engine's normal service procedure, inspect rocker arms and retainers for scoring or play before fitting the shaft, confirm correct seating and endplay, and keep original shims or spacers if fitted. Apply light assembly lubricant to contact points and verify free movement prior to final reassembly.

Tuning and maintenance role: the shaft is a routine service item used during rebuilds or after noticeable valve train wear. A straight, undamaged shaft helps preserve valve timing consistency and prevents accelerated wear on rocker bores and valve guides. Keep the area free from grit and use thread locking where the engine maker advises.