Two-time MotoGP world champion Casey Stoner to retire at the end of this season . The Australian says he no longer enjoys the motorsport as much as he did . - A new report suggests that a third of all Americans are overweight or obese, and more than half have diabetes. Seven-time title winner Valentino Rossi aims to stay in the sport for another two years .
Two-time MotoGP world champion Casey Stoner to retire at the end of this season . The Australian says he no longer enjoys the motorsport as much as he did . The Honda rider tops practice ahead of Sunday 's Le Mans Grand Prix in France . Seven-time title winner Valentino Rossi aims to stay in the sport for another two years .