Bridgestone tests solutions to mark slicks

The two compounds of tyres available to teams have to be visibly different, and the move to slick tyres for 2009 has left Bridgestone needing to work out how best to achieve that.

This year's tyres are marked with a white band at the bottom of one of the grooves, but the new slicks will need to be distinguishable through a sidewall design.

Bridgestone used last week's Monza test to evaluate four different sidewall designs, using a varying number of white line markings, and it is now examining photographs of the test to see which option worked best.

Hirohide Hamashima, Bridgestone's director of motorsport tyre development, said that further tests were likely before a final decision is made.

"We tested the sidewall differences at Monza, and now we are investigating the visibilities after taking photos," he told autosport.com. "We hope to make a decision at the end of this year, but we will still test some more."

Should none of the sidewall designs be deemed good enough, then Hamashima said there was a possibility of Bridgestone marking the actual shoulder edge of the tyre with a white line.

He has also ruled out using any colour other than white, despite red sidewalls having been used in Champ Car in the past.

"Colour is difficult at the moment," he said. "Our machine cannot do other colours, so it is white only at the moment."

Bridgestone has submitted its slick tyre specifications to the FIA, with Hamashima confirming that there will be more difference between the compounds next season.

"There will be a bigger gap I believe," he said. "I believe every compound will have a bit of a bigger difference."