Abstract
Dynamical principles involved in the steering of bicycles, and motorcycles are considered to show the effects of various factors on road worthiness of the vehicles. Special attention is directed to the gyroscopic couples acting on the vehicle, and how some of these couples are utilized to assist in the balancing of the vehicle. Furthermore, the author discussed the steady motion of the cycle in a curve, skidding and side slip on wet surfaces, and the effect of horizontal weight distribution.