Pirelli has decided which compounds they will take to the Bahrain and Russian Grand Prix’s. Choices for the opening round in Australia and the second round in China had already been picked last month.

This falls in line with tyre nominations having to be made for long-haul events 15 weeks in advance, whereas for European races the deadline is nine weeks in advance.

For the first five events of the season, all 13 sets for each driver are identical and defined in the regulations as Pirelli ensure the new wider rubber is up to the required standard. Seven sets of the softest nominated compounds, four sets of the middle compound and two of the hardest compound nominated.

Choices for the opening round in Australia and the second round in China had already been picked last month. Melbourne will see the yellow soft, red supersoft and purple ultrasoft tyres used, with Albert Park being a partial street circuit, utilising the softest rubber will maximise the cars’ potential.

With China known to be a be a bit tougher on tyres, the compounds chosen will be the white medium, yellow soft and red supersofts.

Bahrain always sees high temperatures and with some corners containing high lateral loads, the same compounds from China will be also be used at the Sakhir circuit.

The chosen tyres to be used at the Russian Grand Prix will be the same as in Australia, the very smooth asphalt on the Sochi circuit with little lateral loading corners with Turn 3 being the exception, the tyres don’t take too much punishment.

The size range of the tyre has been completely transformed, with new sizes (305mm wide at the front and 405mm at the rear) as well as new profiles, constructions and compounds.

Pirelli has also announced that the compounds make use of entirely new materials and a completely fresh design philosophy, this is intended to lead to low degradation tyres, this was in line with the driver’s requests to be allowed to push harder during the races.

After a very positive testing programme with the new sizes, Pirelli has decided to additionally homologate a back-up compound alongside each of the five new base compounds. These extra compounds are formulated using more traditional criteria compared to the new base compounds.

For the first part of the championship, only the new-generation base compounds have been selected.

The back-up compounds could be introduced later in the season to respond to any particular requirements once the real performance levels of the 2017 cars have been identified