as do all motorcycle racing schools. Countersteering is included in United States state motorcycle operator manuals and tests, such as Washington, New Jersey, California, and Missouri. Safety According to the Hurt Report, most motorcycle riders in the United States would over-brake and skid the rear wheel and under-brake the front when trying hard to avoid a collision. The ability to countersteer and swerve was essentially absent with many motorcycle operators. The often small amount of initial countersteering input required to get the bike to lean, which may be as little as 0.125 seconds, keeps many riders unaware of the concept. Multi-track vehicles Three wheeled motorcycles without the ability to lean have no need to be countersteered, and an initial steer torque in one direction does not automatically result in a turn in the other direction. This includes sidecar rigs where the car is rigidly mounted on the bike. The three wheeled BRP Can-Am Spyder Roadster uses two front wheels which do not lean, and so it steers like a car. Some sidecars allow the motorcycle to lean independent of the sidecar, and in some cases, the sidecar even leans in parallel with the motorcycle. These vehicles must be countersteered the same way as a solo motorcycle. The three wheel Piaggio MP3 uses mechanical linkages to lean the two front wheels in parallel with the rear frame, and so that it is countersteered in the same manner as a two-wheeled motorcycle. Free-leaning multi-track vehicles must be balanced by countersteering before turning. Multi-track leaning vehicles that are forced-tilted, such as the Carver, are tilted without countersteering the control and are not balanced by the operator. Later versions of the Carver introduced automatic countersteer to increase tilt speed and reduce the force required to tilt the vehicle. Other forced-tilted vehicles may incorporate automatic countersteering. A prototype tilting multi-track free leaning vehicle was developed in 1984 that employs automatic countersteering and does not require any balancing skills. Countersteering by weight shifting With a sufficiently light bike (especially a bicycle), the rider can initiate a lean and turn without using the handlebars by shifting body weight, called counter lean by some authors. Documented physical experimentation shows that on heavy bikes (many motorcycles) shifting body weight is less effective at initiating leans. The following is done when countersteering using weight shifting to turn left: The rider applies a momentary torque, either at the seat via the