Black art of tyre testing!

There is a lot involved in tyres and the art of tyre making but as Adil Jal Darukhanawala discovered, after an exciting tow-day test session with Michelin at the Sepang F1 circuit in Malaysia, tyre testing also comes close to being a voodoo subject best unravelled with experts.

The relentless pace of competition in the automobile industry pervades all facets and none more so than the most critical four black round rubber shoes which help deliver the ultimate in dynamic ability, performance, fuel efficiency and of course safety along with good ride and handling characteristics. No wonder tyre makers today are pushing the design and resultant performance envelope like never before. So when Michelin asked us whether we could hotfoot it to the Sepang F1 circuit on the outskirts of Kuala Lumpur for two days of tyre testing, I thought it would be fun to learn what one of the world's most accomplished tyre makers had lined up for us, by way of contact patch, lateral grip, water dispersion, heat build-up, rolling resistance, etc. Terms and technologies which as one went deeper and deeper into them seemed like an enlightened course both in physics as well as in geometry coupled to psychology (read that as common sense).

The obvious idea behind Michelin's invitation was not just to expound about their new tyres but also to help journos, normally not the most excitable of homo sapiens, experience the latest advances in tyre technology. This learning process used assorted tools which sounded familiar to yours truly, names like BMW, Mercedes­Benz, Porsches, Protons, Volvos and even the humble Toyota Qualis (nee Unser as the MUV is known in Malaysia). And the highly acclaimed state-of-the-art F1 Grand Prix circuit of Sepang formed the canvas on which we were to wield these tools.

On one's own volition, a tyre would just seem to suggest an amalgam of rubber, both of the natural and synthetic kind mixed with carbon black to bond it together along with the addition of silica to give it some magic while nylon and iron cords help in structural strength and so on and so forth. All this is sure to drive any sane person crazy but then designing and manufacturing a car tyre is the blackest art known to the automotive world - pun very definitely intended, and Sepang was where we had to experience and sometimes make our own magic with Michelin's newest.

Speaking of which we had the latest Pilot Sport high performance rubber for sporty applications while on the other hand we had the equally interesting new Energy XMl tyre which holds more of a relevance to the sort of cars you and me and a majority of our countrymen drive. But knowing us, you should have guessed that it would be the wide fat low profile tyres we would be taking to the limit first off. Seems Michelin had read our minds and laid out a test session absolutely spot-on on this count.

Ever since its advent (about a decade ago) Michelin's Pilot Sport has been the preferred footwear for many of the advanced high performance automobiles in the world. The latest generation Pilot Sport builds up on this rep but is a totally new design, insists Michelin. We were asked to try and feel the differences between it and a competitor tyre (which in this case was the Bridgestone Potenza S03 of the type also seen in India – F1 warfare repeated on the streets!) over a series of tests which took in a series of small tests which showed off braking grip and directional ability; a slalom run on dry tarmac and wet weather grip diving down into Sepang's famous right hander first turn followed immediately by the track dropping down going into turns two and three. We used Mercedes-Benz C-class cars and BMW 3-series machines fitted out with both makes of tyres and went through these tests which were interspersed with technical sessions.

Over the course of these tests and instant tutorials, we learnt that not only is the latest Pilot Sport no carryover from the original but is also engineered and built differently for usage in Europe and Asia.

The new sporty rubber encapsulates fresh thought, new compounds and also new construction. Most apparent aspect of the tyre is that its tread design dispenses with the traditional V-shaped rain pattern because as Michelin says, the less the tread pattern is grooved, the more capable it is of resisting deformations when cornering. There was mention of the fact that the tread design was inspired by the quad-groove patterns on Michelin's dry F1 tyres and while it boggled the mind there was quite a different logic which seemed to work.

Michelin has managed to incorporate an assymetrical tread design, putting thicker bands on the outside and deeper, wider grooves on the inside. Michelin's tyre techies explored the natural tendency of a car to lean more heavily on its outer tread going into turns and came up with three solutions to optimise handling. It stiffened the carcass and tread belting to help put a more stable footprint on the road; allowed the gradual deformation of the contact patch (Michelin terms it VCP, short for Variable Contact Patch) to be squeezed over to the outer edge and lastly, it put a dry weather tread compound on the outer bands with a wet weather compound on the inner treads. This juxtaposition of materials took in a high carbon black filler content in the outer tread compound while the inner made do with a 100 per cent silica-filled 'green' compound.

It is easy to dream and design such a tyre but making it is just as exacting a chore but Michelin's tyre manufacturing expertise has state-of-the-art technologies which can handle laying different kinds and grades of rubber in different parts of the tyre in a precise and controlled manner.

Not only has the new Pilot Sport been quick around a race track with very high levels of control and performance, it is also a more silent performer while uniform wear pattern rates have been inbuilt by inherent design itself. Our drives in the Beemers and also in the Porsche Carrera and GT3 went by in a blur that day at Sepang but surely we knew who would get the blame had we spun off or such. But the Pilot Sports really flattered us all and it was only later on the flight back home that I marvelled on the efficacy of this tyre.

After the highs of performance cars and tyres it was on to the regular everyday stuff and I thought it might be boring. But the tests for the Energy XMl along with the twin tutorials were anything but. In fact hustling a Proton Wira and a Toyota Unser (latest generation of the Qualis as sold in Malaysia) so shod was an eye-opener.

The Energy XMl has been designed as a touring tyre for entry level everyday automobiles and also LCVs employing Michelin's green tyre technology and advances in other spheres of tyre design. The ebullient Alain Waha, General Manager, Michelin Asia-Pacific, said that the Energy XMl was targeted at most of the C-and D-segment cars plus MUVs and certain high end B-segment automobiles and well suited to the rigours of Indian motoring as well. Sounds good considering that Michelin begins a new partnership with Apollo Tyres in India and if nothing else, there will be far greater awareness of tyres in the Indian context.