Yokomo S4-002BRLA Aluminum Left Rear Bulk Head for YZ-4S  [S4-002BRLA]

Aluminum Left Rear Bulk Head for YZ-4S

This left aluminium rear bulk head, model S4-002BRLA, is manufactured for the Yokomo YZ-4S family. It replaces the stock left rear bulk head to offer a stiffer mounting location while keeping the chassis' original attachment geometry unchanged.

Fitment is specific to YZ-4S chassis types and the product lists B-YZ4SF among compatible codes; always check your chassis designation before fitting. The machined aluminium construction increases rigidity and reduces wear compared with the OEM plastic component.

From a setup standpoint, upgrading to an aluminium left rear bulk head changes rear load distribution and usually produces a firmer rear feel. Fit this part when aiming for steadier traction and a more rigid rear end for medium to high grip race conditions.

Aimed at competitors wanting a firmer rear mounting point, this aluminium left bulk head integrates into YZ-4S chassis without relocating mount positions.