The front fork and steering post are subject to bending moment due to the reaction from the ground in the direction dcb.
When no brake pressure is applied a bending moment due to the overhang ab is superimposed on these tubes.
Fig. 50 shows the curve of bending moment under one of a series of travelling loads at fixed distances.
The distribution of bending moment is given by the ordinates of a triangle.
The second noteworthy result is that the curvature of the strained central-line is not proportional to the bending moment.
Still harder application of the brake causes a bending moment in the opposite direction.