The present inventor believes that one of the advantages of the present invention is that when washer 66 abuts the second shoulder 76 and the pin 80 is disengaged from the washer 66the assist mechanism 54 is effectively disengaged from pedal arm 32 and does not impact its operation over the balance of its stroke. Thus assist mechanism 54 only has an effect at the initial portion of the stroke of pedal arm 32, as desired.