MotoGP introduces tyre restrictions for 2007.

The MotoGP World Championship will introduce tyre restrictions for the 2007 season - but, at present, they will only apply to Michelin and Bridgestone riders.

That's because a clause has been included which states that the 31 tyre weekend maximum (14 front and 17 rear) only applies to: "Teams that are supplied by a tyre manufacturer that has achieved at least two MotoGP race wins in dry conditions since the first race of the 2005 season."

MotoGP's third tyre supplier, Dunlop, has not taken a single win since the start of 2005 and its riders will thus be exempt from the new restrictions until it "achieves two MotoGP wins in dry conditions". This exemption should help Dunlop close the gap on its competitors and encourage new tyre suppliers to enter the sport.

The 31 dry tyres to be used during a race weekend must be made available "between 12.00 hrs. and 17.00 hrs. on the day prior to the start of official practice" when "the Technical Director will mark the tyres available to each entered rider." This means that Bridgestone and more specifically Michelin will no longer be able to manufacture new tyres overnight after gathering practice data. There will still be no restriction on the number of wet tyres that can be used during a grand prix weekend.

Finally, to avoid the type of farce seen at the 2005 US Formula One Grand Prix - when all the Michelin shod drivers were forced to withdraw from the race, due to the risk of tyre failure caused by a tyre design error - the new MotoGP rules allow an exemption to be made "should an exceptional and unpredictable safety problem arise" whereby three additional sets of tyres (of a different construction) will be given to each rider affected, but those riders will have to start at the back of the grid.

The full rule changes can be seen below:

Technical Regulations

2.9. Tyre restrictions for MotoGP

2.9.1 Wet tyres are not subject to supply restriction.

A wet tyre is defined as a tyre which has a land to sea ratio of at least 20% overall, and a minimum ratio of 7% in each third of the section profile.

The tyre may be moulded or hand cut, but each groove must have a minimum depth of three millimetres over 90% of its length.

Any tyre with a land to sea ratio of less than 20% will be deemed a slick tyre. In case of dispute the decision of the Technical Director will be final.
2.9.2 Prior to the start of the season (defined as the day before the start of the first IRTA MotoGP test of the current year), each team must register the brand of tyre it will be using with the Grand Prix Technical Director.

Should a team choose to change its designated brand of tyre during the season it must inform the Technical Director in writing prior to the start of scrutineering at the event where the change will take place.

2.9.3 Teams that are supplied by a tyre manufacturer that has achieved at least two MotoGP race wins in dry conditions since the first race of the 2005 season will be restricted in the quantity of slick tyres that each of the teams riders may use at a single event as follows:

During all practice sessions, warm up and the race a maximum of 31 slick tyres, specifically -
Front tyres: 14
Rear tyres: 17

When a tyre manufacturer, not subject to the limitation at the beginning of the season, achieves two MotoGP wins in dry conditions during the current season, it will become subject to the restrictions at the third event after the one where the second win was achieved.

2.9.4 Between 12.00 hrs. and 17.00 hrs. on the day prior to the start of official practice, the Technical Director will mark the tyres available to each entered rider.

2.9.5 Each motorcycle entering the track fitted with slick or hand cut tyres (as defined in Art. 2.9.1) must first have its tyres checked for compliance.

2.9.6 In the case of an interrupted race, a rider must use tyres from his allocation of marked tyres for the restarted race.

2.9.7 In the unlikely event of a tyre being accidentally damaged during the fitting process it may be replaced with a tyre of the same specification with the permission of the Technical Director. Such replacement tyres will be marked and included in the allocation of the rider concerned.
2.9.8 Should an exceptional and unpredictable safety problem arise for a manufacturer during an event, so as to prevent a team supplied with its tyres from safely competing in the race, then that manufacturer must inform and prove to the satisfaction of the Technical Director the severity of the problem. The Technical Director may then ask the Race Direction to grant an exemption. Such request must be made before 17.00 hrs. on the day of qualifying practice.

The exemption if granted will apply as follows:

Each rider using tyres supplied by the manufacturer granted the exemption will be supplied with three tyres of a new specification (front and/or rear depending on the determination of the problem). Such replacement tyres will be marked by the Technical Director, and only these tyres may be used in the race.

A new provisional starting grid will be published with all of the riders supplied with the tyres of the manufacturer granted the exemption starting at the rear of the grid in the order of their qualifying positions.