Then, the engineers realized their mistake. Intuitively, they had thought a motorcycle, rolling over to enter a corner, must roll (rotate around a fore-and-aft axis) around its tire footprints. If that were true, speed in roll would increase as major masses were moved nearer that axis (lowered). But if you can find a place on a racetrack where riders come straight at you, brake and then roll into a turn, you can clearly see that they do not roll around their footprints. What you see is the tires counter-steering for the outside of the turn, causing the upper part of the machine to fall to the inside of the turn. Only when the bike is at the desired lean angle do the tires steer into the turn, driving the machine around it.