Revised tyres to be tested but not raced in Canada

Formula One racing's official tyre suppliers Pirelli have announced that they will be providing revised specification tyres in Friday's free practice sessions only in Canada, not for the whole Grand Prix weekend as had been expected. Updated tyres are instead set to make their race debut in next month's British Grand Prix

via Formula1.com - Latest Headlines http://www.formula1.com/news/headlines/2013/5/14621.html