Sunday 2 August 2009

Tires

Tire selection is critical, usually done by the individual rider based on bike 'feel' during practice, qualifying and the pre-race warm-up laps on the morning of the race, as well as the predicted weather. The typical compromise is between grip and longevity—the softer and 'grippier' the tire, the more quickly it wears out; the harder and less grip, the more likely the tyre is to last the entire race. Conserving rubber throughout a race is a specific talent winning riders acquire. Special 'Q' or qualifying tires of extreme softness and grip were typically used during grid-qualifying sessions until their use was discontinued at the end of the 2008 season, but they lasted typically no longer than one or two laps, though they could deliver higher qualifying speeds. In wet conditions, special tyres ('wets') with full treads are used, but they suffer extreme wear if the track dries out.

In 2007 new MotoGP regulations limited the number of tires any rider could use over the practice and qualifying period, and the race itself, to a maximum of 31 tires (14 fronts and 17 rears) per rider. This introduced a problem of tyre choice vs. weather (among other factors) that challenges riders and teams to optimize their performance on race day. This factor was greeted with varying degrees of enthusiasm by participants. Bridgestone had dominated in 2007 and Michelin riders Valentino Rossi, Nicky Hayden, Dani Pedrosa, and Colin Edwards all acknowledged shortcomings in Michelin's race tires relative to Bridgestone. Rossi, disappointed with and critical of the performance of his Michelin tires, switched to Bridgestones for 2008 and won the World Championship in dominant fashion. Pedrosa switched to Bridgestones during the 2008 season.

In 2008 the rules were amended to allow more tires per race weekend—18 fronts and 22 rears for a total of 40 tires. The lower number of tires per weekend was considered a handicap to Michelin riders. The only MotoGP team using Dunlops in 2007, Yamaha Tech 3, did not use them in 2008 but switched to Michelin.

For 2009, 2010 and 2011, a 'spec' tire supplier, Bridgestone, was appointed by the FIM (Michelin no longer supplying any tires to MotoGP). For the whole season Bridgestone will provide 4 different specifications of front tyre, 6 of rear, and a single wet specification—no qualifying specification. For each round, Bridgestone will provide only 2 specifications for front and rear. Tyres will be assigned to riders randomly to assure impartiality.[4]
[edit] Chronology

* 1949: Start of Grand Prix motorcycle racing.
* 1973: Deaths of Jarno Saarinen and Renzo Pasolini at the Italian round at Monza.
* 1982: The Yamaha OW61 YZR500 is the first V4 in the 500cc class.
* 1984: Michelin introduces radial tires in GPs.
* 1987: Push starts are eliminated.
* 1988: Wayne Rainey wins the first 500cc race using carbon brakes, at the British GP.
* 1990: 500cc grid switches from 5 to 4 bikes per row.
* 1992: Honda introduces NSR500 with big bang engine.
* 1993: Shinichi Itoh and fuel-injected NSR500 break the 200 mph barrier at the German GP at Hockenheim.
* 1998: 500cc switch to unleaded fuel.
* 2002: 990cc 4-strokes allowed in premier class.
* 2003: Daijiro Kato dies, leading to Suzuka's removal from the roster.
* 2004: MotoGP grid switches from 4 to 3 bikes per row.
* 2004: Makoto Tamada earns Bridgestone their first MotoGP victory at the Brazilian GP.
* 2005: MotoGP adopts flag-to-flag rule, meaning races continue if rain begins.
* 2007: MotoGP restricted to 800cc 4-strokes.
* 2008: Dunlop drops out of MotoGP.
* 2009: Michelin drops out of MotoGP and Bridgestone become sole tyre providers.[5][6]
* 2009: Kawasaki Suspends MotoGP activities for 2009 and considers privateer team.

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