TRF421X Upper Suspension Arms Upgrade 51765 for TRF421 by Tamiya  [51765]

TRF421X Front Upper Arm Replacement

The Tamiya 51765 TRF421X A parts consist of two pcs of upper suspension arms intended for 1/10 scale touring car use, supplied as a pair for simple replacement or an upgrade. They are compatible with the TRF421X (item 42391) and the TRF421 (item 42384), enabling spare use or tuning swaps without significant changes to mounting hardware.

These arms are molded in carbon reinforced nylon to provide controlled flex along with thermal stability, aiding predictable suspension performance on high-grip and carpeted circuits. The material choice aims to deliver toughness while retaining enough compliance to affect traction and steering feedback without raising the risk of brittle failure.

Installation is straightforward as a direct swap on TRF421-series chassis using existing hinge pins and fixings. When fitting, confirm hinge pin alignment and suspension travel, and then check camber and toe settings. As part of a tuning strategy, these arms can be used to subtly alter front-end feel for improved handling where grip is increased.