Monday 20 July 2009

de Motocyclisme

A Road Racing World Championship Grand Prix was first organized by the Fédération Internationale de Motocyclisme (FIM) in 1949. The commercial rights are owned by Dorna Sports. Teams are represented by the International Road Racing Teams Association (IRTA) and manufacturers by the Motorcycle Sport Manufacturers Association (MSMA). Rules and changes to regulations are decided between the four entities, with Dorna casting a tie-breaking vote. In cases of technical modifications, the MSMA can unilaterally enact or veto changes by unanimous vote among its members.[1] These 4 entities compose the Grand Prix Commission.

There have traditionally been several races at each event for various classes of motorcycles, based on engine size, and one class for sidecars. Classes for 50cc, 80cc, 125cc, 250cc, 350cc, and 500cc solo machines have existed over time, and 350cc and 500cc sidecars. Up through the 1950s and most of the 1960s, four-stroke engines dominated all classes. In the 1960s, two-stroke engines began to take root in the smaller classes. By the 1970s, two-strokes completely eclipsed the four-strokes. In 1979, Honda made an attempt to return the four-stroke to the top class with the NR500, but this project failed, and in 1983, even Honda was winning with a two-stroke 500. The 50cc class was replaced by an 80cc class, then the class was dropped entirely in the 1990s, after being dominated primarily by Spanish and Italian makes. The 350cc class vanished in the 1980s. Sidecars were dropped from World Championship events in the 1990s (see superside), reducing the field to 125s, 250s, and 500s.
Yamaha YZR-M1 MotoGP bike

MotoGP, the premier class of GP motorcycle racing, has changed dramatically in recent years. From the mid-1970s until 2002 the top class of GP racing allowed 500cc with a maximum of 4 cylinders, regardless of whether the engine was a two-stroke or four-stroke. Consequently, all machines were two-strokes, due to the greater power output for a given engine capacity. Some two- and three-cylinder two-stroke 500s were seen, but though they had a minimum-weight advantage under the rules, typically attained higher corner speed and could qualify well, they lacked the power of the four-cylinder machines. In 2002, rule changes were introduced to facilitate the phasing out of the two strokes, probably influenced by what was then seen as a lack of relevance: the last mass-produced 500cc 2-stroke model had not been available to the public for some 15 years.[original research?] The rules permitted manufacturers to choose between running two-strokes engines (500cc or less) or four-strokes (990cc or less). Manufacturers were also permitted to employ their choice of engine configuration. Despite the significantly increased costs involved in running the new four-stroke machinery, given their extra 490cc capacity advantage, the four-strokes were soon able to dominate their two-stroke rivals. As a result, by 2003 no two-stroke machines remained in the MotoGP field. The 125cc and 250cc classes still consist exclusively of two-stroke machines. In 2007, the MotoGP class had its maximum engine displacement capacity reduced to 800cc for a minimum of 5 years.

The 2008 racing calendar consisted of 18 rounds in 16 different countries (Spain which hosted 3 rounds, Qatar, Turkey, China, France, Italy, Great Britain, the Netherlands, Germany, Czech Republic, San Marino, Portugal, Japan, Australia and Malaysia). Exclusive to the MotoGP class, there was also a USA round at Mazda Raceway Laguna Seca in Monterey, California for the 800cc class only, as California's strict emissions law bans two-stroke motorcycles. In 2008 a MotoGP event was held at the Indianapolis Motor Speedway for the first time on a newly prepared track, and observers noted that the Speedway had hosted motorcycle racing before cars raced there. All three classes were scheduled to race but severe wind and rain prevented the 250cc class from racing. MotoGP racing at Indianapolis is counterclockwise, starting on the Formula One track, with additional turns directly after the pit area, bypassing the banking turn one of the oval track. Also because of the race being run counterclockwise on what is normally a clockwise track, the run off areas have seen significant modification.

The grid is composed of three columns (four for the 125cc and 250cc classes) and contains approximately 20 riders. Grid positions are decided in descending order of qualifying speed, the fastest on the 'pole' or first position. Races last approximately 45 minutes, each race a sprint from start to finish without pitting for fuel or tires.

In 2005, a flag-to-flag rule for MotoGP was introduced. Previously, if a race started dry and rain fell, riders or officials could red-flag (stop) the race and either restart or resume on 'wet' tires. Now, if rain falls a white flag is shown, indicating that riders can pit to swap the motorcycle on which they started the race for an identical one, as long as the tires are different (that is, intermediates instead of wets, or slicks instead of wets)[1]. Besides different tires, the wet-weather bikes have steel brake rotors and different brake pads instead of the carbon discs and pads used on the 'dry' bikes. This is because the carbon brakes need to be very hot to function properly, and the water cools them too much. Hence the conventional steel brakes. The suspension is also 'softened' up somewhat for the wet weather.

When a rider crashes, track marshals wave a yellow flag, prohibiting passing in that area; one corner back, a stationary yellow flag is shown and passing in this area of the track is prohibited; if a fallen rider cannot be evacuated safely from the track, the race is red-flagged. Motorcycle crashes are usually one of two types: lowsides and the more dangerous highsides, though increased use of traction control has made highsides much less frequent.

According to one estimate, leasing a top-level motorcycle for a rider costs about 3 to 3.5 million dollars for a racing season.[2]

As a result of the 2008-2009 financial crisis, MotoGP is undergoing changes in an effort to cut costs. Among them are reducing Friday practice sessions; banning active suspension, launch control and ceramic composite brakes; extending the lifespan of engines; reducing testing sessions.

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