A bicycle should be incredibly easy to knock over. It has only two wheels, a narrow contact patch, and no obvious mechanism keeping it balanced. Yet once you're moving, a bicycle can feel remarkably stable—even though the same bicycle can be almost impossible to balance when standing still.

So how does it stay upright?

In this episode, we explore the fascinating physics and engineering behind bicycle stability. We dive into steering geometry, wheel motion, angular momentum, tire contact, trail, rider control, and the subtle feedback mechanisms that allow a bicycle to correct itself before it falls.

We examine why the front wheel can automatically steer into a fall, how the rider constantly makes tiny corrections without consciously thinking about them, and how the geometry of the bicycle affects its ha ...