Pirelli is concerned by lock-ups on the rear tyres which are "going right the way through the belt pack".

The tyre manufacturer was in the spotlight during 2013 for a number of tyre failures, but has taken a more conservative approach to this season in order to avoid a repeat. However, during an exclusive interview with Crash.net, Hembery said problems with the new brake-by-wire system has led to occasions when the tyres are suffering significant damage.

"Something new that we've been observing is on the brake-by-wire for example, we've seen a few more lock-ups and flat spots compared to the past on the rear," Hembery said. "That's something that we're looking at closely to try and understand what is going on, because they're not just flat spots they're actually very dramatic going right the way through the whole belt pack. So it's not just a superficial thing that you would just release and carry on, it's something that would stop you.

"So things like that we're checking; of course I'm sure that will change as the teams get used to the new vehicles but it's something that we're looking at from our point of view and it's something that we're raising saying: 'Look, go careful'."

While Hembery says he expects the situation with the rears to improve, he also said flat spots on the front tyres have been less dramatic during pre-season than in 2013.

"As you've seen some people have had a huge spin, locked up all four and basically ground their way through the whole tyre! There's not a lot you can do there. It's so extreme at the moment that it would stop you anyway, but it's degrees of flat spot as well. So while we may not get the bigger flat spots that we've seen in the initial days of testing, if we get something in between then it can still become a significant issue if you decide to keep running and you don't make a tyre change. So it's an area that we're always monitoring.

"In general we've seen on a classical type of flat spot and a lock-up in braking then the cars are able to continue. There's less of an impact compared to last year and they're able to brush it off. So that's a positive, but it's the extreme lock-ups which we've seen that we're keeping a watching brief on."