The physics of bike balance

One of the glorious mysteries of the bicycle is how, even without a rider, it can stay balanced while rolling at speed. There are a couple of different commonly shared theories, but none of them tell the whole story.

Luckily, the fine folks over at MinutePhysics have posted a youtube video that explains it magnificently:

But amazingly, even for a riderless bike, science currently doesn’t know what it IS [emphasis theirs] about the special combinations of variables that enables a bike to stay up on its own.