AT MICHELIN, WE ARE REALLY SHARP! Certain Michelin tyre fitters, called 'dissectors', have a special art and manner to handling a knife while they cut or strip tyres. Re-cutting... for extra water clearance In...
AT MICHELIN, WE ARE REALLY SHARP!
Certain Michelin tyre fitters, called 'dissectors', have a special art and manner to handling a knife while they cut or strip tyres.
Re-cutting... for extra water clearance
In very heavy rain, Michelin's technicians may be called upon to cut extra grooves in the pattern of rain tyres to transform them into 'maxi' rain tyres by enhancing their water clearance capacity.
"This technique is only rarely used at Le Mans," points out Matthieu Bonardel. "You don't get the phenomenon of standing water because of the good drainage of the portion of track that is generally open to everyday traffic. Also, the drivers want to cover as many stints as possible with the same tyres, and the more you re-cut a tyre the less durable it becomes. We only re-cut if we haven't got the ideal rain tyre for a given situation, as we did yesterday.
"Extra circumferential grooves can be added for enhanced lateral grip, while extra grooves to the shoulders improve traction."
Dissection and analysis
After their long, demanding workout on the track, the tyres' ordeal is not entirely over since a proportion of them is consequently dissected and analysed, a job that calls for an extremely trained eye...
As soon as tyres that have raced are returned to the Michelin compound from the pits, they are removed from the rim and a proportion of them is set aside for dissection. During the Le Mans 24 Hours, two 'dissectors' are on permanent standby for at least the first eight to ten hours of the race. At other events, the technicians who look after the prototype and GT teams dissect the tyres themselves.
The aim is to analyse how the tyre has functioned on the track with a view to passing on information that could serve for the stints to come. The tyres are cut and their cross-section is inspected to make sure their structure hasn't become deformed in any way and ensure that the tyre has performed in accordance with expectations. Information for the teams
"If all is OK, we can authorise those teams that so wish to double or triple stint," observes Michelin engineer Alain Charnier "We inform them that the wear of their tyres is perfect and that they can cover more stints if they want to, but we never force them. That said, we may occasionally warn against triple stinting."
The other reason for dissecting the tyres is to ascertain why a punctured has occurred, essentially for the benefit of the media. It is possible to see whether a puncture was caused by an impact or by perforation of the tread. Tyres occasionally come off the car and are left on the track, in which case it can take some time for the technicians and team personnel to recover them. At other times, the cover is so damaged that it is impossible to analyse it. In the vast majority of cases, however, the dissection process reveals the true story.