Physics – 1.5.3 Centre of gravity | e-Consult

A bicycle is more stable when moving than when stationary due to the gyroscopic effect and the continuous adjustment of the rider's position to maintain the bicycle's balance. The key principle is the interaction between the bicycle's motion, its centre of gravity, and the base of support (the two wheels).

When stationary, the bicycle's CG is relatively close to the point of contact between the wheels and the ground. This means that even a small imbalance can easily cause the CG to move outside the base of support, leading to a fall.

However, when the bicycle is moving, the gyroscopic effect of the rotating wheels provides a stabilizing force. This force resists changes in the bicycle's orientation. Furthermore, the rider constantly makes small adjustments to their body position to keep the CG aligned with the bicycle's frame and the line of motion. This continuous correction helps to maintain the CG within the base of support. The combination of gyroscopic forces and rider input allows the bicycle to remain balanced even when moving, as the rider can actively counteract any tendency for the CG to drift outside the base of support.