Motorcycle Racing

The history of motorcycle racing began with the development of the internal combustion gasoline engine in the latter years of the nineteenth century. The first motorcycles were bicycles to which a crude engine was attached to the rear wheel to provide power.

As with the development of early racing automobiles, the first competition motorcycles were built in a variety of styles, as racing pioneers experimented with both two and three wheel configurations. The first motorcycle race involving exclusively two wheel designs occurred at Surrey, England, in 1897. The sport quickly became popular in both Europe and the United States; the world body responsible for the establishment of motorcycle racing standards, the Federation Internationale de Motorcycles Club, now known as the Federation Internationale de Motorcylcism (FIM) was founded in 1904.

Motorcycle racing evolved in two distinct directions—competitions organized according to the nature of the racing to be conducted, and races open to specific sizes of motorcycle engines, a determination based upon either engine displacement (measured in cubic centimeters) or the degree of customization permitted to the motorcycle. The first motorcycle races were held on open road courses, the most famous of which is Great Britain's Isle of Man TT (or Tourist Trophy) event, first staged in a number of different classifications in 1907. Hill climbing races and dirt track racing on both quarter mile (400 m) and half mile (800 m) ovals became popular in the United States in the 1930s. This form of racing has continued to the present day, on surfaces where the racers regularly exceed speeds of 100 mph (160 km/h).

Specialized closed circuit road tracks, similar in concept to the courses built for Formula 1 automobiles, were constructed in various parts of the world to accommodate the extremely high powered performance racing motorcycles beginning in the 1970s. This form of racing, organized as "MotoGP," involves motorcycles that are built for racing only, as opposed to stock motorcycles that race in other racing classifications: stock motorcycles are very similar to those available for public use through commercial sale.

The MotoGP class of motorcycles are so powerful that the engines must be de-tuned, a process where the otherwise available power of the motorcycle is mechanically restricted, to permit the rider an opportunity to control the motorcycle that has the capacity for tremendous speeds but relatively little contact between the tires on the machine and the surface of the track, when compared to a racing automobile. The small degree of tire contact restricts the amount of control that the rider can exercise over the MotoGP motorcycle by way of braking or cornering if the machine were permitted to travel at its maximum available speed.

Motor cycle drag racing, where the machines race on quarter mile (400 m) paved strips also promoted the use of sophisticated engine technologies, where modified engines 1300 cc and larger cover the distance at speeds in excess of 150 mph (241 km/h) at the quarter mile marker. Motorcycle drag racing in the United States is organized under the auspices of the National Hot Rod Association (NHRA), the organization that organizes automobile drag racing. The motorcycle drag races are known as the Pro Stock Bike series.

Motorcycle racing became a popular off road venture, from smaller scale motocross events that are staged both indoors on modified surfaces that include artificial jumps and moguls to challenge the racers, to the dangerous multi-day endurance racing events such as the Paris to Dakar, Africa event. These motorcycles are constructed with heavy suspensions to absorb the significant forces that are generated when the machine is bouncing on a dirt trail or other off-road surfaces.

Motorcycle racing requires an understanding of a number of different physical principles. One of the most dramatic of these applications is observed when a racer executes the racing technique known as cornering. On a closed course racing circuit, the riders will be observed with the motorcycle angled into the turn, with the rider's inside knee positioned very low, appearing to skim over the track surface as the motorcycle moves at high speeds through the turn.

As the rider corners, three different physical elements are at play to influence the movement of the motorcycle: the downward pull of gravity upon the motorcycle and rider, the friction between the tires and the track surface, and the centripetal force acting to the outside of the turn. The perfectly executed turn will be the product of the rider leaning the motorcycle at an angle where the force of gravity is at equilibrium with the centripetal force that is acting to force the motorcycle upright. If the lean into the turn is too acute, the motorcycle will fall over; if the lean is insufficient, the motorcycle cannot make a sharp, efficient turn. If the rider enters a turn with no lean at all, the motorcycle is likely to fall towards the outside of the turn.

One common feature to almost all types of motorcycles is the acceleration capability of the machine. If the motorcycle accelerates too rapidly, the front wheel will be pushed off the ground, a phenomenon known as a "wheelie." Some wheelies are executed by motorcyclists as a stunt; the wheelie when unexpected can flip the motorcycle over on its longitudinal axis.