Yokomo BD9 MID Topdeck 2.0mm Chassis Stiffener - Arrowmax AM-910020  [AM-910020]

BD9 MID Upper Plate for Precision Tuning

This Arrowmax AM-910020 topdeck is a direct-replacement upper plate made for the Yokomo BD9 MID layout, specified at 2.0mm thickness. It links the front and rear bulkheads and contributes to the overall torsional stiffness of the touring car chassis.

The part is intended for setup tuning: changing topdeck stiffness alters mid-corner balance and transient response without changing suspension geometry. Fit this deck where the BD9 MID topdeck is specified to maintain original mounting alignment.

Fitting is straightforward on standard BD9 MID cars—remove the existing topdeck, line up the mounting holes and tighten screws evenly to keep the deck flat. When testing, make single-variable changes and record lap times and driver notes to isolate how stiffness affects understeer, oversteer and straight-line stability.

As an aftermarket option for the Yokomo BD9 MID chassis, this topdeck suits hobbyists who prefer a methodical setup approach; use it to evaluate chassis stiffness changes as part of a staged tuning plan.