(CNN) -- Formula One is supposed to be about drivers racing fast cars, but this season it seems to be all about the tires. There have been complaints from teams and drivers, with an official investigation also underway over a development test, while the latest twist involves Pirelli putting its plan on hold to introduce new race tires at next month's Canadian Grand Prix. Instead, each of the 22 drivers will be given two sets of development medium compound tires to try out during the first practice session at the Gilles Villeneuve Circuit in Montreal on 7 June. A statement by the Italian manufacturer explained: "The Formula One teams will have an opportunity to test the new range of Pirelli tires during free practice at the Canadian Grand Prix, while the tires used for the actual race will remain in their original 2013 specification.
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Pirelli put plans to introduce new race tires at next month's Canadian Grand Prix on hold
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Each of the 11 teams will instead try out development tires in the first practice session
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Pirelli wants to change tires to stop delaminations
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Mercedes face an FIA investigation over involvement in tire test
The FIA is now investigating the matter but neither the governing body or @placeholder expect a resolution before the Canadian GP.