LONDON, England - McLaren's sporting director Sam Michael has taken a refreshing approach to his Formula 1 team's pit-stop problems by promising the beers will be on him if the crew gets to average three seconds a stop.Pit stops have troubled the British F1 team so far in 2012 and 2008 champion Lewis Hamilton suffered from glitches again in his two stops on the way to winning in the 2012 Canadian GP on June 10.With no time-consuming refuels allowed during the race any more, mechanics aim to complete a tyre change in under three seconds; a driver in Canada can be in and out of the pits lane in 21 seconds under a 60km/h.'THREE-SECOND CHALLENGE'"Obviously we put a lot of effort into our stops," Michael told Sky television at the Circuit Gilles Villeneuve. "It's almost like a football team now, the way we put the energy in. We were regularly doing two and half second stops all the way through practice."The challenge is for them to beat three seconds; they've huge motivation because I've already offered the whole team a round of beers the moment they average a three-second stop."They failed to achieve that on Sunday but, Michael said, the times were still a big improvement. "The first stops were so good that neither driver reacted in time and we lost reaction time, dipping about five-tenths quicker than we have ever done," he said.Hamilton recognised that he might have been at fault on that one, with the car going into anti-stall briefly when he released the clutch.'RIGHT-REAR FASTEST'On the Briton's second stop there was a brief delay on the right rear wheel - long enough for Hamilton's singer girlfriend Nicole Scherzinger to bang the table in exasperation as she watched in the garage. Michael cleared the mechanic of any blame."Our right rear-gunner, who is actually the fastest gunner, the re-cock mechanism on his gun didn't re-cock so when he went back on it was still in off mode. He had to modify his gun and go again," he said. "He's our best guy and actually hasn't had a fault all year. Because of his experience I knew he'd recover it and he did."The rear-left had been in the spotlight previously, responsible for sluggish stops in Bahrain and China for Hamilton and Jenson Button respectively. That crew member was replaced after Bahrain, when pit processes were also reviewed.