TRF421X/TRF421 Upper Suspension Arms (x2) - Tamiya 51765  [51765]

Front Upper Arms for TRF421X

The Tamiya 51765 TRF421X A parts are supplied as a matched pair of upper suspension arms for 1/10 scale touring car use, provided as two pcs for straightforward replacement or upgrade. They fit the TRF421X (item 42391) and are also compatible with the standard TRF421 (item 42384), so you can carry spares or change parts without altering existing mounting hardware.

Manufactured in carbon reinforced nylon, these arms retain controlled flex and thermal stability to help preserve predictable suspension behavior on high-grip tracks and carpet surfaces. The material balances toughness with measured compliance to influence traction and steering response while avoiding brittle failure modes.

Installation is a direct swap on TRF421-series chassis using your existing hinge pins and fasteners. When installing, check hinge pin alignment and suspension travel, then verify camber and toe settings after replacement. As a tuning option, these arms can subtly change front-end feedback to refine handling for higher-grip conditions.