A new European labelling scheme for car tyres, designed to help you choose the right rubber, will become compulsory in November 2012. Manufacturers are already jostling for position ahead of its introduction, so we took a look at the scheme ahead of its full launch to give you the key lowdown on what it all means.
Why the new labels?
The label scheme is being put in place to demystify the process of choosing a suitable make of tyre. From November 2012, it will become a legal requirement for tyres to bear labels modelled on those found on white goods such as fridges and washing machines, which are considered easy to interpret. Between then and now, displaying the labels is voluntary, but there’s nothing to stop you asking to see them before making a purchase.
What do the labels show?
Each label will show the results from three standardised tests: straight-line braking performance in the wet, the fuel economy impact of rolling resistance, and an external noise rating, which will show how much of a din the tyres make as they roll along the surface of the road.
How do I read the labels?
The wet grip and economy results are displayed through both a colour-coded gradation from green to red as well as a score from A to G, where A is top of the class and G is the underachieving dunce. The external noise rating is shown as a tyre icon with one, two or three curved black lines meant to suggest sound waves. Three black lines indicates the kind of tyre that should come with free earplugs.
So tyres with two As and one sound wave are best?
Not necessarily. The grading scheme was supposed to be a tough test, designed to foster technical innovation, but some manufacturers claim the labels can be misleading.
In June Pirelli announced its new Cinturato P7 Blue, aimed at premium sports saloons and similar cars, and boasting top marks for both efficiency and grip. Rival maker Michelin, by contrast, has settled for an A for wet grip paired with a B for rolling resistance with its new generation Energy Saver+ tyre, designed for more modestly powered cars with rims up to 16 inches in diameter.
However, Michelin has vigorously attacked the idea that gaining an A in both tests would indicate a superior product.
So there are other factors to consider?
Tyres are more subtle and complex than fridges and there’s much more to a good tyre than braking in the wet, fuel consumption and noise. "The motorist doesn’t only care about those three," said Vincent Rousset-Rouviere, the man in charge of Michelin’s car and van tyres across Europe. "There is also dry road safety -- we know that 70 per cent of accidents occur on dry roads -- and there is also lateral grip, comfort and longevity." The implied criticism is that the new rating scheme will incentivise tyre makers to sacrifice a variety of desirable qualities that happen not to show on the label.
So A-rated tyres might actually be rubbish?
It is likely that something has had to give to get a double-A score, so you may find that the tyre wears out more quickly than you’d like, for example. Michelin has developed a double-A tyre but only for a niche market with unusually skewed demands. The Energy E-V, an upcoming tyre developed for electric cars and due to be fitted as standard to Renault’s Zoe ZE, scores top marks for both wet grip and economy, but Michelin’s experts don’t recommend fitting it to conventional cars. They cite a variety of concerns, prominent among them the fact that it’s not rated for use above 160km/h (about 99mph).
Why is it so complicated?
Slice a cross section through a modern tyre and the complexity of its construction becomes clear. There are precisely aligned cables and fibres, interleaved layers of rigid and more pliable rubber, and even an electrically conductive slice to carry away static electricity. Meanwhile the visible tread pattern is more complex than meets the eye. The size of the blocks governs not just grip and stability in corners but also sound -- smaller blocks generate a higher frequency noise that is easier to suppress inside the cabin.
The upcoming label will give consumers more information, but it will paint only a simplified and subjective picture of the complex engineering that goes into making a top-performing tyre.
How do I choose the best tyre for me?
Unfortunately the new label will not make it much easier to pick the best tyre because of all the qualities it doesn’t reveal. If you are shopping for high-performance rubber for a powerful sports car, for example, don’t be alarmed at a low score for economy. And because cornering is similarly ignored by the label, a suspiciously cheap tyre with a great looking label might still send you hurtling off the road at the first bend.
One of the most important considerations -- how long the tyre will last -- isn’t addressed at all and durability may vary quite a bit. German standards agency Dekra recently tested comparable tyres from Bridgestone, Continental, Goodyear, Michelin and Pirelli over more than 18,000 miles of real roads, and found substantial variations. It calculated that the Continental tyre would need replacement at 22,000 miles but that the Michelin would manage 29,000 miles, with the rest falling somewhere in the middle. This big variation in value is not reflected in the label at all.
So despite the EU’s efforts to shed more light on the business of buying rubber, an old adage may still ring true. You’ll probably get what you pay for.