Kubica: BMW development not quick enough

Although Kubica gave BMW Sauber their maiden victory at the Canadian Grand Prix, the team struggled for pace in the next race in Magny-Cours, where Kubica lost the championship lead after finishing in a distant fifth.

The Pole reckons that BMW have been losing ground to Ferrari and McLaren since the start of the season, and he also believes rivals like Red Bull or Renault are catching up on them.

Kubica is aware that he has benefited from their rivals' problems to be in the championship hunt, but he fears that he will lose contact once McLaren and Ferrari start having trouble-free races.

"To be honest, with our car, even at full performance we can do fifth," Kubica told reporters during testing at Silverstone. "It's not enough.

"But fortunately sometimes McLaren and Ferrari have technical problems, and sometimes the drivers help us a bit with some mistakes, and that's why we are still there.

"But if they start to not have problems and not make mistakes it will be very difficult to keep up with them. I will always try to score as many points as possible."

The BMW driver believes that unless the team can find more speed quickly, Ferrari and McLaren will be out of reach for good.

"I think we have improved less since Australia than everybody else, so that's the reason," he said.

"Also, Renault and Red Bull are closer to us than at the beginning of the season, so we have to find some parts which will give us better handling, better top speed and better pace. If we lose again in the next couple of races, the gap to Ferrari and McLaren... we will never catch them.

"In Australia we were quicker than Ferrari. In Malaysia and Bahrain we were quicker than McLaren. In Barcelona we had already quite a big gap to Ferrari but still keeping close to McLaren.

"And then afterwards, McLaren in some occasions joined Ferrari. Ferrari did improve and it looks like we didn't as much as them. The gap is pretty big and in Magny-Cours it was nearly one second."

Kubica reckons the team made a mistake when choosing some parts for the French Grand Prix, but the Pole is adamant that BMW will be back as the third quickest team in Silverstone next week.

"I think we made some mistakes when choosing some new parts for Magny-Cours," he added.

"We tested some things in Barcelona, and I saw some things, but we chose something different because the team was convinced this was the right way to go and it wasn't.

"Okay, we are not as fast as Ferrari, but in Magny-Cours we dropped behind teams like Toyota, Renault and even Red Bull.

"It was coming partly from what we had chosen for this grand prix, and at this test we are trying to understand what was it.

"And for Silverstone we should be back to normal pace, so it means there's still quite a big gap to Ferrari and McLaren but in front of everybody else."