BARCELONA (Reuters) - Formula One drivers have been warned about their pace on the pre-race formation lap after some complained of having to drive too slowly and others of being kept waiting at the front.
Championship leader Nico Rosberg, the only driver other than Mercedes team mate Lewis Hamilton to have started on pole position this season, told reporters at the Spanish Grand Prix that race director Charlie Whiting had discussed the issue.
"Charlie clarified it for both sides, so the people further back are not allowed to leave the big gaps and we at the front need to keep up the pace," said the German, second on the grid for Sunday's race with Hamilton on pole.
The pace of the formation lap is a consequence of the new V6 turbo era and the energy recovery systems that provide a boost from the battery.
Lotus driver Romain Grosjean said the new regulations meant everyone was seeking different ways of keeping heat in the tyres and ensuring the battery did not drain too much before the start.
"It is a fact that the engines are not very powerful on that (formation) lap and that makes the thing messy," the Frenchman said.
Hamilton, who has been on pole four times in five races so far, admitted he had been experimenting with different approaches.
"In the drivers' briefing they said there are no rules to how fast or how slow you can go, so I've gone from one extreme to another," he said after of the situation before Whiting's clarification.
The Briton recognised he had maybe gone too far in one direction, particularly at last month's race in China.
"You're trying different things to prepare your tyres in a better way. If you push in the first part of the lap your tyres and brakes are good and then you have to slow down to let everyone catch up," Hamilton added.
"In that period of time the temperatures drop so fast. So you are trying to minimise that... if you start doing your burnouts and get to your grid spot, and then have to wait there for over a minute whilst everyone forms up, your temperatures drop and you can potentially get a worse start."
(Editing by John O'Brien)