pedal end 210 if the proper holes have been selected as pivots the arm 300 is made of resilient material and is formed in a bowed shape it acts as a compression spring between the pedal 200 and bracket 400 when force is transmitted to the arm 300 by the bolts 23 and 34 the ability of the arm 300 to rotate about those bolts prevents them from exerting any bending force on the arm 300 thus the forces on the arm 300 are purely compressional acting along a line between the bolts 23 and 34 due to the bowed shape of the arm 300 such an applied force tends to bend the arm 300 into a more deeply bowed shape as the amount of bow increases so does the bending force along the arm as a result the 34 spring constant 34 of the arm 300 changes with increased bowing due to increased force this means that for the arm 300 the spring constant is not constant mother way of saying this is that the arm 300 is a non linear spring which does not obey hooke 39 s law either a linear spring or a non linear spring in the linkage of the invention would affect the dynamic leverage that is the instantaneous.