Countersteering

From Wikipedia, the free encyclopedia

Countersteering is the name given to the "counter-intuitive" technique used by cyclists and motorcyclists to turn corners.

1 How it works
2 Motorcycles
3 See also
4 External links

[edit] How it works

When riding a bicycle or a motorcycle, countersteering is a method of initiating a turn by a small, momentary turn of the front wheel, usually via the handlebars, in the opposite direction. While necessary at all speeds, the need to countersteer becomes more noticeable as speed increases.

A bike can negotiate a curve only when it leans towards the inside of the turn, at an angle appropriate for the velocity and the sharpness of the turn. Otherwise centrifugal force will tip the bike and rider over towards the outside of the curve. The transition of riding in a straight line to negotiating a turn is a process of leaning the bike into the turn.

If a rider wants to turn to the right, he first throws the bike off balance by momentarily pointing the front wheel slightly to the left. The center of mass of the bike plus rider will continue in a straight line, but the contact patches of the tires move to the left with respect to this straight line. As gravity then tips the bike over to the right, the front wheel is steered into the curve, and the curve is negotiated with the proper inward lean. This process usually requires little physical effort, because the geometry (rake and trail on motorcycles) of the steering of most bikes is designed in such a way that the front wheel has a strong tendency to steer in the direction of a lean.

At low speeds countersteering is equally necessary, but the countersteering is then so subtle that it drowns in the continuous corrections that are made in balancing the bike.

Once in a turn, countersteering is again required to make changes to its shape. The only way to decrease the radius at the same speed is to increase the lean angle, and the only way to increase the lean angle, is again to momentarily steer opposite to the direction of the curve. To the untrained, this can be extremely counter-intuitive.

To exit a turn, countersteer by momentarily steering further in the direction of the turn. This tilts the bike back upright.

Countersteering is indispensable for bike steering. Most people are not consciously aware that they employ countersteering when riding their bike. Their body has learned to include the well timed countersteering jolt. They may have learned to do so while learning to ride a bicycle in childhood. Often people simply assume that the steering of a bike is just like the steering of a car. Their subconscious balance skills know better.

[edit] Motorcycles

Even more so than on a bicycle, mastering the technique of countersteering is essential for safe motorcycle riding, and as a result is a large part of the safe riding courses run by the Motorcycle Safety Foundation. At the higher speeds that motorcycles commonly travel, it becomes increasingly impractical to steer by taking advantage of the minute and random corrections needed to maintain balance. Much of the art of motorcycle cornering is learning how to effectively "push" the grips into corners and how to maintain proper lean angles through the turn.