Axle Plates & Adjustments on Ultra Lightweight Manual Wheelchairs One of the most frustrating situations for a seating and mobility therapist is to see an active manual propeller reaching back for their rear wheel because the center of gravity setting is in the most rearward position. All ultra lightweight manual wheelchairs allow for center of gravity adjustments. This is accomplished by moving the rear axle forward or backward along the axle plate. The clinical recommendation for active users is to adjust the rear axle as far forward as possible without compromising the stability of the user. 4/29/2019 Keep Reading