HPI Bullet 3.0 MT/ST Rear Alloy Arm Upgrade GPM BMT056 by GPM  [BMT056]

Stiff alloy rear arm for HPI Bullet 3.0 platforms

The GPM BMT056 is an alloy rear suspension arm engineered for HPI Bullet 3.0 MT and ST cars. It serves as a direct replacement for the factory plastic arm, preserving stock geometry while offering increased rigidity for nitro short-course applications.

The content covers fitment pointers, simple installation checks, and how the arm influences chassis tuning. Upgrading to alloy improves repeatability when pushing hard, reduces flex that can upset cornering, and gives a more robust option for frequent off-road sessions.

Use normal RC workshop checks during installation: confirm ball stud and pivot pin condition, torque mounting screws correctly, and recheck alignment settings after fitting to maintain consistent handling.