A Wheelie, when the front tire of a motorcycle is off the ground. A wheelie is a careful balance between throttle and weight distribution. As seen in the image above, there are two main components of balancing the bike. The first, is the position of the bike, as well as the rider’s position. Assuming that the bike is moving at a constant speed, the main component that affects the balance point is the rider’s position. If the bike is observed on its own as a free body diagram, the center of mass is to the left of the axis of rotation, which is the axle of the rear tire. If the rider’s center of mass is analysed on its own it is to the right of the axis of rotation. Therefore, when the two free body diagrams are combined the resultant force is directed through the axis of rotation. The force causing objects to rotate or twist is called torque, the force times distance perpendicular to the axis of rotation. The resulting force travels directly through the axis, or parallel to the axis of rotation; no torque is created and no rotation occurs. When the torque on the axle of the rear tire is zero, the bike will be perfectly balanced and will be able to ride with the tire off the ground.
