Propulsion of scooters

A scooter having a frame, a steering post in the front portion of the frame, a front wheel supported on the post, a fork at the rear of the frame, a rear wheel rotatably supported in the fork, a ratchet mechanism for driving the rear wheel, a stepping lever for transferring the stepping force of the rider to the ratchet mechanism, a retrieving means for raising the stepping lever to the original position as the stepping force is released therefrom and a releasing means for disengaging the ratchet mechanism, wherein the ratchet mechanism comprises a rotational ratchet wheel, a ratchet pawl for intermittently driving the ratchet wheel pitch by pitch and a set of transmission gears for amplifying and transferring the rotational length of each motion pitch of the ratchet wheel to the rear wheel, wherein the stepping lever comprises a horizontal portion, one end of which is hingedly mounted on the frame, a vertical portion extending from the other end of the horizontal portion, and a pin transversely extending from the horizontal portion for hingedly mounting said ratchet pawl whereby the ratchet pawl can be rocked by the stepping force applied on the stepping lever to intermittently push the ratchet wheel to rotate pitch by pitch, wherein the releasing means is disposed above the ratchet pawl and there is a spring stretching between the ratchet pawl and the stepping lever whereby the ratchet pawl can be moved downwardly and disengaged from the ratchet wheel by the releasing means when the stepping force is in a released state and retrieved to the original position and engaged with the ratchet wheel by the spring as the stepping force is applied on the stepping lever, and wherein the stepping lever further comprises a second horizontal portion transversely extending from an end of the vertical portion to a position above a mid-portion of the frame, a second vertical portion extending from the second horizontal portion and a pedal hingedly linked at the top end of the second vertical portion.