The team had a poor start to the season, and were involved in controversy over the minimum weight of their cars (see below), and were disqualified from one race, banned from another two. The team failed to score a point until the French Grand Prix. However, the team's fortunes were turning slightly, and Jenson Button scored points in all of the last 10 races, including two podium finishes. Takuma Sato only scored one point in the entire season, and was subsequently sacked from the team.

The 007 was a clear evolution of the BAR 006, which had been highly successful for the team, leading to their second place in the 2004 championship behind Ferrari. The new 007 car was a much tighter design and overall it was smaller than the previous 006. BAR designers also managed to save significant weight over the 006 car, despite greater safety testing being required for the 2005 season.

The engine and gearbox were not left untouched either. For the 2005 season, engines had to last 2 races. Honda created a brand new V10 unit, which was smaller, lighter and had a better centre of gravity than the 2004 engine. The gearbox was also an evolution of the 2004 unit, with some modifications to allow it to fit in better with the new tight design.

Both BAR-Hondas were disqualified from the San Marino Grand Prix after it was found the cars could run below the minimum weight, stated by the FIA regulations of 605 kg. BAR disagreed with the report, claiming the cars could not run with less than 6 kg of fuel, therefore that pushed them over the minimum weight. They also claimed that they thought it was during race weight the rules meant, not in post-race scrutineering. The FIA decided to punish the team, banning them from two races, including the Monaco Grand Prix. Jenson Button acted as a summariser for ITV F1 in the Monaco Grand Prix, as he could not compete. BAR were going to contest the disqualification, but later changed their minds. Max Mosley wanted to have the team disqualified from the entire season.

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Wikipedia