Pirelli's Paul Hembery surprised by criticism for being too conservative

Speaking at AUTOSPORT International, Hembery said he believes Pirelli had delivered on its targets for its first season in 2011, ahnd that along with the DRS and KERS, that its tyres had provided a boost to the racing in F1.

"We accept that we were part of that package and it's hard to divide out all the factors from the three technologies," he said. "At the end of the season it was quite strange sometimes to be criticised for being conservative. When we started the year we had everybody saying we had pushed it too far the other way.

"I think overall we are very happy and we need to try and replicate that in 2012.

"It was very hard to do [to create tyres to a multi-pitstop format]. People don't understand how difficult. If you get it wrong and the tyres lasted say 200km then you are back to one change per race. To give the three tyre stops that we were asked to do meant that we had a lot of work to do.

"Twenty circuits, 12 different chassis and 24 drivers to try and balance that out with only four compounds was extremely difficult."

Pirelli is set to make significant changes to the branding on the tyres in an effort to answer criticisms that it was too difficult to tell which drivers were using which compounds during races, according to Hembery.

"We did make some changes after Singapore - we used a different type of branding - but we are going to increase the width of the bands on the tyres and we believe that will help to recognise what tyres are on the car," said Hembery.

"We are working with FOM management to make sure there are some on-screen graphics to ensure the viewer knows which tyres are on the car and we will have to wait and see after the first race to see if that has worked."

Hembery said work continues on finalising the compounds for 2012 and he remains satisfied with the direction of the development.

"The hard, medium and soft compounds are changing," he said. "We are making the performance differences between them much closer together and faster as well.

"We've changed the profile on the rear tyre and done a bit of work on the construction to try and get a little bit more footprint because we assume, maybe incorrectly, that there will be a little less downforce in 2012 - at least at the start of the season.

"But with the knowledge we now have, because not every circuit was known to us before F1, then we can make more aggressive compound selections for each race.

"Martin Whitmarsh gave a comment in Brazil when he said he wants Pirelli to challenge us again and push the barriers so that's what we will be trying to do."