I think Pirelli are to blame as they changed the tyre construction for 2013. Tyres have been failing all season but nothing has been done.
The reasons Force India, Ferrari and Lotus didn't want the tyres changed was to do with compounds. Mercedes and RedBull wanted hard compounds, which suit their cars, but the others felt they would loose their advantage as their car designed used to tyres more efficiently.
Pirelli have tried all season to play down the problem, and have carried out tests with a 2011 Ferrari and the 2013 Mercedes to try and find a solution.
A tyre with a Kevlar belt was taken to Canada, but due to the wet conditions not enough could be learnt about the tyre for all the teams to agree on its use. The tyres were also used in Friday practice at Silverstone and these maybe the tyres that are used in Germany.
http://www.bbc.co.uk...rmula1/23122185
The delaminations, it seems clear now, were a consequence of Pirelli's decision to change the construction for this season, to go for a radial tyre, with a softer sidewall and steel belt (the material that runs around the circumference if the tyre, beneath the layer of rubber), rather than the hybrid crossply/radial of last season, which was stiffer, and had a Kevlar belt. The join between the sidewalls and tread was not as tough and was failing under stress.
On the other was the fact that the tyre compounds - the durability of the rubber - had been changed to make them softer. The teams who were struggling with this - notably Red Bull and Mercedes - were campaigning for harder tyres. The teams who had good tyre durability - Ferrari, Lotus and Force India - rejected that argument.
Pirelli took a tyre with a different construction, which it intended to introduce at Silverstone, to Canada three weeks ago, for the teams to try in practice. But it rained, so not enough running was done to reassure the teams that this would not change the behaviour of the tyre, in the way Ferrari, Force India and Lotus were concerned it would.
Edited by surfblue63, 03 July 2013 - 02:39 AM.