52 BMWcar
TECH TALK
TYRES
They might be round, black and sticky, but there’s a lot more
to tyres than you might think, as Elizabeth de Latour explains
Photos: Nankang and Toyo
T
yres are just tyres, right? Wrong, so very wrong. Tyres are incredibly complex and the ratio of the various
materials used during construction results in very diff erent compounds with diff erent properties. We
see a lot of people scrimping on tyres where they’ve otherwise spent £1000s on other areas of their
car, which is very strange, as your tyres are the only things keeping you attached to the road.
You might think those budget tyres are fi ne, until you hit that standing water, encounter that slippery
corner or that out-of-the-blue emergency braking situation.
Only then, when the chips are down, will
you fi nd that, actually, they’re not.TREAD MATTERS,
RIGHT?PART
ONE
Understanding
There’s a common misconception
with tyres that all that matters is the
tread pattern. But that’s like saying that
the £10 trainers from the market are
the same as a pair of Nikes, because
they look the same. Amazingly I’ve
have heard people saying that surely
budget tyres will perform the same as
high-quality ones because the tread
pattern looks exactly the same.
However, simply copying the tread
pattern from premium brand rubber
doesn’t make a good tyre that will
perform equally as well as its much
more expensive relation. There’s a lot
of subtlety and expertise that goes
into modern tread design and the
good ones are diffi cult to replicate
eff ectively. Then there’s the rubber
itself. The compound mix used has
an incredibly infl uential eff ect on
how well a tyre performs, and a poor
choice will result in a poor tyre.
Generally speaking, the contact
patch on a set of four tyres – that’s
the actual arear of rubber touching
the road surface at any one time,
is about the size of an A4 sheet of
paper. That’s all there is giving you
your front-end grip and your rear-end
traction; it’s what’s enabling you to put
the power down and helping to stop
you when you jump on the brakes.
That’s it, that’s all you’ve got and that’s
why it’s always so important to fi t the
best tyres you possibly can.