Yokomo S4-303MSA Slipper Main Shaft for YZ-4SF  [S4-303MSA]

Slipper main shaft for YZ-4SF

This S4-303MSA item is a replacement main shaft intended for the slipper assembly of YZ-4SF scale RC cars, listed as a standard part for that chassis. The core role of this shaft is to secure the slipper components while allowing the designed slip characteristics to protect drivetrain parts during high load events on the model.

Compatibility is defined by the supported chassis code B-YZ4SF, so installers should verify their model code matches that chassis designation before ordering. The listing specifies this as a standard spare part rather than a modified upgrade, so it is intended to match the original form and fit for YZ-4SF slipper assemblies.

Installation normally involves partial disassembly of the slipper unit to remove the old shaft and fit the replacement, checking alignment and engagement of the slipper pads or springs during reassembly. When servicing or tuning the slipper, use this shaft as a direct swap to restore factory slipper positioning and engagement behavior.