Tyre chiefs to question rules

Just one week after Toyota technical director Mike Gascoyne called for a more thorough clarification from the FIA about possible loopholes in the regulations, especially when it came to when teams were allowed to change tyres if they hit problems, now the tyre manufacturers admit there are grey areas.

Bridgestone's technical manager Hisao Suganuma has said that it is almost certain that the teams cannot head into the season with the current level of doubts they have about what is and what is not allowed.

"Eventually, we as well as Michelin have to get clarification from the FIA before the season," he told autosport.com. "Or maybe we have to go via the teams to get a clear understanding of the rules."

One of Suganuma's chief concerns is that under his current interpretation of the rules drivers are only allowed to change tyres if they actually have a puncture - and not on safety grounds if there is excessive wear that could lead to a potential blow-out.

"A serious flat spot can cause so much vibration that it can endanger the driver and if that is the case then can we not change it?" said Suganuma. "If there is no deflation but the surface has broken up, revealing the casing itself, then it is very dangerous. However, at that stage it cannot be treated as a puncture.

"Reading the regulations, you cannot change the tyre until the air has escaped - but if you carry on driving with the broken surface then there may be a puncture. I think it is then dangerous, but how does one judge it?"

The problem of damaged tyres is further complicated by the fact that drivers will be allowed to change tyres if they have run over 'unavoidable debris' - although proving such a matter may become incredibly complicated.

"'Unavoidable debris' is one the clauses I am not quite sure about," added Suganuma. "If a driver insists that he has run over a piece of debris, is he allowed to change the tyre?

"The rule allows that, but how do you prove he has actually run over some debris? Do you need testimony from marshals? Or do you need video footage to prove it? I do not know how to police this..."

The FIA has always maintained that it is willing to clarify any doubts about its regulations if it is approached by competitors.