In
the days of yore the only Indian cars worth considering were the only
cars available. As an impressionable youngster who used to hang around
car enthusiasts, I used to always hear that this tyre is no good because
it could do only around 20,000km before the tread vanished. Tyre life
over all else seemed to be the mantra of the everyday car user and I remember
even our family car, which used to be a Hillman Minx then, would seemed
to go on and on forever.
Things changed dramatically in 1980s with the advent of the Marutis and
also the ushering in of the radial revolution. Suddenly we started hearing
things like grip and steering responses and ride comfort and fuel efficiency
and not just tyre life.
More than anything else, it was growing awareness levels among car users
that saw many veering towards the radial tyre. The compromise between
comfort (radial deflection), and steerability (sideways stiffness) was
not possible with the traditional (read that as cross-ply) tyre structure
as with the radial ply tyre. A radial casing alone offers no improvement
but if it also comes with a reinforced belt structure it retains the high
comfort factor of its radial-ply nature with the added virtues of steering
controllability.
 Moreover,
it allowed designers to adjust the two factors in relation to each other
as required for a particular type of car. In contrast to the radial, the
cross-ply is now comparatively limited as far further development is concerned,
even in India. I qualify this by suggesting this statement holds good
for passenger car application tyres only.
Radials may be about 25 per cent costlier than similar sized cross-ply
tyres but they may give upto 8-0 per cent more mileage and also afford
the other intangible benefits in superior ride quality and better grip
and control, factors which have become common-speak even in India today.
With the advent of radials came the stylised looks as well. Of course
this came thanks to the wide squat rubber used by racing cars but automotive
stylists were quick to pick these cues and design them into their new
automobiles. The designers wanted wheels of a certain overall diameter
but they wanted them to also accommodate the brake discs and part of the
hub carriers. This helped give us the lowered height-width ratio and even
though we have had low profile cross-ply tyres as well, the radial handles
low profiles infinitely better-just ask Ferrari or Mercedes-Benz or BMW
or Porsche.
It
was this battle for low profiles and great grip with better cornering
stability which brought the tubeless tyre to the fore. In the early days
thanks to rubber compounds and tyre constructions being at the technological
levels prevailing then, the tubeless tyres took some time perfecting.
But once the virtues of lower unsprung weight, easy repairability, better
ride quality and many more factors which only magnified the radial tyre
advantage became apparent, the tubeless radial has gone on to capture
market share in the developed lands.
The tubeless movement is now making its advent in India getting off the
ground with makers like Goodyear with its Trinuum Tyre Tech. From the
cross ply to the radial to the tubeless, tyres have surely come a long
way.
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January 2002
