Pirelli switch to kevlar belts in tyres after drivers' threat to boycott German Grand Prix The statement added: "In the meantime, the FIA has asked Pirelli for an assurance that there will be no repetition of the tyre problems at this weekend's German Grand Prix or at subsequent grand prix." Pirelli will give those assurances at the meeting of Formula One's Sporting Working Committee on Wednesday, but is not expected to encounter any resistance. Ferrari, Lotus and Force India - the three teams who opposed the switch in Canada - all agreed to put safety before their own interests in the wake of Sunday's fiasco. Adrian Newey, Red Bull's chief technical officer, had hit out at the "short-sightedness" of those three teams. "It's a sad state of affairs but such is the nature of Formula One, really," Newey said after Sunday's race. Pirelli came up with a solution [but] two or three teams vetoed that because they were worried it would suit some other teams more than it would suit them. As a result of that short-sightedness, Formula One ended up putting up the worrying performance it did [at Silverstone]. Pirelli believes that what occurred at Silverstone was in fact a completely separate issue from the delamination which prompted the tyre manufacturer to propose the belt switch in Canada. Kevlar belts might have made a difference on Sunday but it is unclear whether they would have prevented the blow-outs altogether. After extensive analysis, Pirelli believes the tyres "fatigued" under the heavy loads put through them at the high-speed Silverstone circuit. This year's cars are much faster than last year's - up to two seconds per lap - which means far heavier loads go through the tyres. And since Pirelli was unable to test with current race cars due to the ban on in-season testing, it found it difficult to replicate the sorts of loads experienced on Sunday. The stress on the tyres at Silverstone was aggravated by the high kerbs at Turn Four, which cut into them. This led to the blow-outs, either afterwards on the Wellington Straight or later in the lap. Pirelli is not thought to be attaching any blame to the Silverstone track, so much as saying the kerbs exacerbated an underlying issue. Derek Warwick, president of Silverstone's owner the British Racing Drivers Club, dismissed as "absolute rubbish" any suggestion the circuit's kerbs were to blame. "These kerbs have been in since 2009 and we have had thousands and thousands of cars go over them and they weer absolutely fine," Warwick told Sky Sports News. We have had them checked by the FIA and they conform fully. For me, Bernie, the FIA and Pirelli are bringing the sport into disrepute and they need to have a serious look at themselves. The Sporting Working Committee will also discuss having a tyre test in Brazil after the final race of the season at Wednesday's meeting.