The role of the gyroscopic effect in most bike designs is to help steer the front wheel into the direction of a lean. This phenomenon is called precession and the rate at which an object precesses is inversely proportional to its rate of spin. The slower a front wheel spins, the faster it will precess when the bike leans, and vice-versa.[42] The rear wheel is prevented from precessing as the front wheel does by friction of the tires on the ground, and so continues to lean as though it were not spinning at all. Hence gyroscopic forces do not provide any resistance to tipping.[43] At low forward speeds, the precession of the front wheel is too quick, contributing to an uncontrolled bikes tendency to oversteer, start to lean the other way and eventually oscillate and fall over. At high forward speeds, the precession is usually too slow, contributing to an uncontrolled bikes tendency to understeer and eventually fall over without ever having reached the upright position.[11] This instability is very slow, on the order of seconds, and is easy for most riders to counteract. Thus a fast bike may feel stable even though it is actually not self-stable and would fall over if it were uncontrolled. A bicycle wheel with an internal flywheel for enhanced gyroscopic effect is under development as a commercial product, the Gyrobike, for making it easier to learn to ride bicycles. Another contribution of gyroscopic effects is a roll moment generated by the front wheel dur

ng countersteering. For example, steering left causes a moment to the right. The moment is small compared to the moment generated by the out-tracking front wheel, but begins as soon as the rider applies torque to the handlebars and so can be helpful in motorcycle racing.[9] For more detail, see the countersteering article. Precession is a change in the orientation of the rotational axis of a rotating body. It can be defined as a change in direction of the rotation axis in which the second Euler angle (nutation) is constant. In physics, there are two types of precession: torque-free and torque-induced. In astronomy, "precession" refers to any of several slow changes in an astronomical body's rotational or orbital parameters, and especially to the Earth's precession of the equinoxes. See Precession (astronomy). A Gyrobike[1] is a bicycle with a Gyrowheel for its front wheel. The Gyrowheel contains a motor-driven flywheel that spins independently, and uses the principle of gyroscopic precession to help stabilize the bike and the rider. Precession responds to a lean of the bike by turning the front wheel in the direction of the lean, which can help provide stability at low speeds, whether riding straight or turning. The Gyrobike was invented by a group of four students at Dartmouth College for an engineering project. Product development is also underway on an adult-sized Gyrobike intended to provide continuous stability for disabled, elderly or other riders.