Pirelli says experimental hard tyres unlikely to return before the Japanese Grand Prix

Pirelli's motorsport director Paul Hembery reckons the firm's experimental hard tyre will not be seen again until October's Japanese Grand Prix weekend at the earliest after rain spoilt its evaluation in Hockenheim practice

Although some teams ran the new hard on Friday morning, the intermittent rain meant no conclusive data could be gathered. Rain had previously prevented Pirelli from trying the tyre in Silverstone practice as it had originally hoped.

"We had a few laps, but we learned absolutely nothing, basically. That's it for that one," said Hembery.

"We'll have to think of doing something later in the season. Ideally I'll like to take it to Suzuka and have a go there if we can get them rebuilt in time. Or failing that, certainly Brazil, or something at the end of the year.

"There's not really much point in Monza, and we haven't got time for Spa."

Pirelli does not intend to introduce its revised hard this year as it does not want to interfere with the title battle in the event that the tyre spec proves more suitable for some cars than others.

The company's priority is to get data to evaluate how differently the 2012 Formula 1 cars use the tyre compared to the 2010 Renault it uses for development testing.

"We wanted to try and better understand the correlation between what we see on a 2010 car and on this year's cars, because this year's cars have been so different, it's been hard for us to correlate what we see on our own test car with what we see on the track," Hembery explained.

"We don't see the same temperature deltas between front and rear as we've seen on some cars here. We haven't maybe seen the sensitivities that some cars have had.

"But having said that, the cars are evolving very quickly and we're maybe starting to see a return to a bit more equilibrium in the way that we had last year. We expect over the next few races to see the order changing as it normally does."