Bridgestone Motorsport concluded two pre-season tests at Jerez last Saturday, where extensive use was made of Bridgestone's wet and intermediate tyres for the majority of eight days' testing at the track in southern Spain.

The final two days provided extensive dry running, but prior to that uncharacteristic and persistent rain made matters difficult for teams trying to develop their new cars.

Three compounds of 2010 specification dry tyres were available, with all but the super soft on offer, but it was the wet and intermediate tyres which were used for the majority of the time. Such was the demand for these tyres that Bridgestone sent extra sets of both for all teams from its UK base.

Bridgestone's Potenza Formula One tyres will next be used in test action this week at Barcelona where all four dry compounds as well as the wet and intermediate will be available.

How much of a factor has the weather been in Jerez?
Jun Matsuzaki - Assistant Technical Manager, Bridgestone Motorsport: "I think this is the most rain ever seen at Jerez, and on Thursday night it was almost impossible to leave the circuit as there was so much water on the roads. Fortunately, there was no more rain left in the sky so we had good dry running on Friday and Saturday which was very valuable."

What are the difficulties with testing in wet conditions?
JM: "The difficulty with wet conditions is that they are never constant so there are too many variables to gain good data and develop cars. If it is raining, the circuit is getting wetter so lap times become slower because of this. If it is a drying track, there will be improving lap times due to the improved track surface, a change to the car, or use of a different tyre. This makes it very difficult for everyone. Also, logistically, we had to bring out extra wet and intermediate tyres to enable the teams to continue running in these difficult conditions."

How have the wet and intermediate tyres worked in Jerez?
JM: "The difficult factor has been that these tyres have been used before the teams have been able to get good dry set-ups on their cars. This is important to have as it makes finding a wet set-up far easier. This has meant we've seen a variety of wear characteristics, particularly on the intermediate tyre which is used on a drier track than the wet. When the intermediate is used on a track which has dry patches, or on a car where the set-up is not so balanced, you do see more wear with this tyre. The additional weight of the fuel loads in this season's cars also adds to the difference in wear from that seen before. Equally, Jerez is a circuit which has quite high wear so we expect better performance as teams develop better set-ups of their cars and at less severe circuits than Jerez."

What have you learnt about the dry tyres?
JM: "Saturday was the only day where we started with a dry track and we had very little rain through the day, so we are still working with limited data. We can say that warm-up has been good for all three dry compounds here, with a definite improvement from last season's tyres. It is too early to understand the differences between the compounds. Jerez is particularly severe on the rear tyres and we are happy with their performance from what we have seen so far. Hopefully, we will have better weather in Barcelona."