“Some riders did comment that the drive grip, that is the grip when the rider picks up the machine from full lean angle when accelerating out of corners, was better on the harder rear slick, but edge grip, which is important at the flowing Jerez circuit, was better on the softer rear option - even in the very hot temperatures.
“Race simulations in practice revealed that the rate of wear on the softer rear slicks was sufficient for the race distance, and this is why every rider selected the softer rear tyre on Sunday.”
Azuma then hinted that the strong performance of the softer tyre made the harder compound look bad - and pointed out that the harder rear had been taken to victory, by Marc Marquez, at the previous Austin round. Marquez and Stefan Bradl are the two riders who have started a 2013 race with the harder tyre.
“The fact that the wide operating temperature range and durability of our softer rubber compounds provided consistent performance over a race distance is positive for us,” he said.
“We had a similar situation at Austin two weeks ago. At that time only two riders selected the harder rear for the race, but the difference is that one of these riders ended up winning the race! In this case riders could lap at a similar pace with harder rear tyre, whereas at Jerez they could not.
“We believe this was due to the character of the tarmac and the very high track temperatures in Spain.”
But Azuma left the door open for possible changes.
“We will now analyse the data we have from the race to see if there are any lessons to be learned for our future tyre development and race compound selection,” said the Japanese, himself a former grand prix winner.
“As we know, the machine weight has increased by three kilograms this year, and so we are investigating what affect this change - plus the fact that teams have now had a year to develop their chassis, electronics and power delivery to work with our latest generation of MotoGP tyres - has had on tyre performance and will apply these lessons to the development for our next generation of tyres.
“After pre-season testing and three races we now have a substantial amount of data with which to start developing the tyres for the 2014 season, which we will present to riders for evaluation later in the year.”