Yokomo S4-203AA Aluminum Internal Servo Mount for YZ-4S Chassis  [S4-203AA]

Internal aluminum servo post for YZ-4S

The Yokomo S4-203AA is an aluminum internal servo mount made for YZ-4S scale touring car chassis. It is produced as an inside-chassis post that positions the servo body to create a firm connection to the steering mechanism. This component is intended to be used alongside the matching outside mount post and a graphite servo mount plate engineered for the YZ-4S chassis to finish the setup.

Installation tips: the mount fits inside the chassis and secures the servo via the internal post interface, therefore the external post and graphite plate are required to clamp the servo. Verify servo spline and horn alignment before final torque, and ensure the mount clears adjacent parts in the chassis to prevent binding.

Tuning impact: a machined aluminum internal mount reduces flex between the servo and steering linkage, helping maintain steady steering input. Small tweaks such as changing plate thickness or adding shims at contact points can adjust servo height and roll centre without altering the overall chassis geometry.

Compatibility

Designed for YZ-4S style touring chassis and listed as compatible with B-YZ4SF mounting patterns; confirm your chassis mounting layout before fitting.

Select this mount when you need a compact, stiff internal servo mounting option for YZ-4S builds, and combine it with the specified external post and graphite plate for a complete installation.