Turning the handlebars briefly to the right makes the bike lean to the left because of gyroscopic precession, and it is the leaning that accomplishes the turning. (The reader may recall a classroom demonstration of gyroscopic precession involving a spinning bicycle wheel that one holds by its axle, while seated on a chair that is free to swivel. Tilting the axle—that is, trying to rotate it on a horizontal axis perpendicular to the axle itself—is hard to do, and makes the chair you are sitting in swivel on a vertical axis. It is a very weird experience; there seem to be demonic forces at
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