Tyre tests

Tyre tests: which tests can you trust, and how far?

Some motorists, when choosing tyres, take various tests published online and in print media as gospel. And it happens that they are later surprised at how a little-known tyre they used to run performed far better in real life on the road than the current celebrated (and not cheap) winner of authoritative tests.

You need to understand that any test, and a car tyre test especially, is a very subjective exercise. So you can and should read test results, but it is still better to make the final decision with your own head, rather than blindly trusting the tests.

Have you ever wondered why a tyre that has earned millions of glowing reviews from motorists and is a clear sales leader in a given region or even a whole country does not appear in the top five in its segment in various authoritative tests in its first year, but only shows up there once it has already proven itself, in its second or third year on the market? Why that way round, and not the other?

He who pays the piper calls the tune?

Why are test results always subjective? There are many reasons, and the main one is the very thing any test starts with: choosing which tyres to compare. If out of the couple of hundred different tyre models sold on the market, only 18 or 20 are tested (compared against each other), you can work out for yourself how representative that sample is.

What is more, tyres are tested against a whole range of parameters, each of which is given a certain weight to arrive at the final score. The range of parameters, and even the testing methodology itself, can also be adjusted in any direction by the test’s author or client.

So, even assuming the results are entirely reliable and transparent, it has to be said that the subjective preferences of the test’s author or client still have a very serious effect on the outcome. That is why the value and objectivity of tests commissioned or funded by this or that tyre maker is extremely doubtful, and the real client or sponsor is far from always disclosed. And any tyre test involves quite a lot of trials and costs a considerable sum. Just ask yourself who is paying for all these tests, and why.

And it is worth noting that this is not only, or even mainly, about plain old “paid-for coverage”, meaning rigging the results in favour of a particular tyre - it is more that the organisers and people who run every test are living people, with their own tastes and preferences, and their own personal driving conditions - and it is far from certain that all of that is fully relevant to you.

How independent are “independent” tyre tests?

The best-known and most popular independent tests are run by the German motoring club ADAC. The results this organisation publishes can, with a small stretch, be considered fairly objective, but they are mainly relevant for European countries.

You need to understand that road quality in Europe is substantially different from what a motorist in Ukraine is used to, and the generally accepted style of driving and road behaviour there is very different from ours. So the criteria used for comparison, and the weight each of those criteria carries in the overall score, do not always match the real needs of the average motorist in Ukraine.

Here is a telling example: ADAC tested eighteen winter tyres, and not one of them was a studded tyre or a tyre with a Nordic tread pattern. All 18 were high-speed winter tyres (the so-called “European winter”). And the criterion for how tyres behave on snow (stability, starting and braking) accounted for only 25% of the overall score put together. How much can the results of a test like that really tell a driver whose winter morning often starts with digging a channel through the snow with a shovel to get out of the yard or the garage?

Tests carried out or commissioned by Ukrainian motoring publications, sadly, cannot be treated as the final word either, because all too often they fall prey to subjectivity and a bias towards particular manufacturers.

How do you read a tyre test?

Start reading any test not at the podium but at the list of entrants. Sometimes a piece is titled “winter tyres”, but only studded models with one type of tread are compared in it - even though studless tyres, and tyres with an asymmetric or classic tread, would have had different characteristics. In that case it is worth asking yourself: who was this test actually made for, the tyre makers or the consumer? Look, too, at who is missing from the table: if the direct competitors of the entrants sell quite happily alongside them but for some reason were not included in the trials, what you have in front of you is not a market ranking but the editors’ own list of preferences, nothing more.

You can only compare like with like. The places won in one tyre size do not carry over to another: it is far from certain that the same tyres in a different size would finish in the same order. And remember that with bad roads, for winter it is actually better to fit a narrower tyre with a higher profile, if the car manufacturer allows that size, whatever anyone says about how respectable a low profile looks.

Find the table of weighting coefficients and recalculate it for your own winter. It is that table, not the text of the article, that decides who won. In a big city in winter, what is usually under your wheels is dry, and even more often wet, tarmac generously doused in de-icing chemicals, and braking on tarmac is exactly the weak point of studded tyres; whereas on ice and snow a driver’s attention and caution rise involuntarily, by instinct. Notice, too, that fuel consumption often gets a noticeable share of the score for a negligible difference in the measurements, while wear resistance, meaning how many miles you get from one set, is not tested at all. The noise of studded wheels is also scored, even though they are all noisy.

Check what the report leaves out. Which car was the testing done on, and which electronic systems - ABS, traction control, stability control - were switched on, and which were switched off? Different tyres behave differently with these systems and without them, so the places in the ranking may turn out different from what you would find on your own road. It would not hurt to state which instruments were used, and under what conditions, to measure speed during the lane-change manoeuvre, the time round the ice circuit under power, and directional stability.

The name of a famous proving ground tells you about the precision of the measurements, but not about the objectivity of the exercise as a whole. Testing centres, as a rule, do not run trials on their own initiative or out of charity, because the trials themselves are the whole point of their business. It is the client who decides the line-up of entrants, the set of disciplines and the weight each discipline carries in the final score, while the proving ground supplies the conditions and the equipment. Objectivity depends on the client, and on the client alone.

Of course, it is easier to criticise than to do. I have great respect for the journalists who put together material like this: among them there are very often genuinely professional and useful pieces of work. But there cannot be such a thing as a perfect test in nature, because every motorist has their own conditions, their own preferences and their own driving style. So judge any test above all by how closely its authors’ conditions match your own.

In any case, tyre tests should be treated as additional information, not as the final word, because to one degree or another these tests are an element of marketing.