A lift assist system for lifting a tow bar and setting a tow bar-actuated brake system. The lift assist system includes a cam that may proportionally counter the moments imposed on the tow bar for a reduced and more uniform exertion force on the tow bar throughout the rotation of the tow bar. A brake actuation system can help provide retention of the tow bar in the upright configuration, eliminating the need for or providing redundancy to conventional latch and hook mechanisms.

A brake assembly for a personal mobility vehicle, in form of a racing wheelchair, comprises a brake lever for actuating a brake cable, wherein the brake lever is a 3D printed glass filled nylon unit, in particular with up to 30% glass filled nylon. A steering arm assembly comprises a steering arm with the brake assembly integrated into the steering arm A racing wheelchair with one front wheel is attached to a wheelchair frame via a fork, with two drive wheels as well as a steering cage mounted on the rear of the wheelchair frame. The brake assembly and/or the steering arm assembly are mounted to the wheelchair frame.