Perhaps I may be much too sensitive, but it does get on my nerves, when someone sitting in a stationary car does a 'burnout' until the tyres smoke or even burst. I'm sorry, but I just don't see the point. They apparently, have no respect for those who designed the tyres nor for those who actually made them. To make matters worse, the more expensive the tyres are, the more often they are senselessly burnt away.
The governing bodies in Europe are taking a better road. They are making a new tyre-labelling compulsory. From November 2012 onwards this will be mandatory for all new motor car and truck tyres, not however, for motorcycle-, oldtimers and retreads. Did the respective lobby help in getting the ordinance watered down? Whatever the case may be, the actual value of the labels, like the labelling of household appliances, is very much doubted, as far as winter-tyres are concerned it is even described as being useless.
Three aspects are indicated by various colours: The rolling friction, the grip on wet roads, particularly when braking and the noise development. The green 'A' shows top-performance, the descriptions go down in steps to 'G', which e.g., means an 18 meter longer braking distance. The added braking distance is distributed evenly among the other letters, which means, for each letter, an additional 3 meters.
As far as assessing the noise they make, the driver can't really judge, in this case it's primarily all about the sound that is emanated when they pass. An interesting point is, that the manufacturers test themselves, albeit according to legal guidelines. This is something that one should be aware of, before one places one's trust in the label of the cheapest provider.
Here, it's all about safety and the environment. This is why, apart from the noise they make, also the rolling resistance is stated. This has to do with the CO2-emission of our cars, after all, the engine has to produce the torque that the tyres partly absorb. Of course at the moment, they are working on all the sections of the drive train to minimize the friction, e.g., also on the wheel-bearings.
One can demonstrate the rolling resistance of todays cars, even under normal traffic conditions, all one has to do is let the car roll (making sure no-one is behind you). Against an oldtimer having approx. the same weight, the modern car car would win hands down. On a flat strech of road, at around 50 km/h, there is only one resistance that becomes more important, that is the wind.
Unfortunately, tyres can be compared with a table cloth that is too small. If you pull it into place on the one side, then the gap on the other side becomes bigger. Thus the above tyre, gets top marks for low rolling resistance and in the wet, which it very likely loses again as far as other aspects are concerned. This probably doesn't bother the drivers of electric cars, it will certainly bother the others. Only rarely in the development of tyres, can one or two components be improved without worsening others.
In this respect, winter-tyres are a good example. For the apparent better grip in the wet the durability will probably have to take a back seat. It's a pity that it's typical qualities at low temperatures cannot be found on the new labels. They are simply not tested under such conditions. Thereby, it would be interesting to find out something about their grip on snow covered roads, which probably has a lot to do with the type and the depth of their tread. Also interesting is the lower amount of artificial caoutchouc used in favour of the naturally harvested rubber in winter tyres.
Let's stay, for the moment, with the very important aspect of rolling resistance. If one wishes to find out more, in conversations with the engineers responsible one repeatedly comes up against a barrier called 'trade secret'. At this point e.g., the discussion with manufacturers of brake-pads, is over very quickly. With clutch-pads, those in the know hold out a little longer. So, what about tyres? Dead right, one doesn't get very far with them either. Obviously, in the tread-material, there is still potential to reduce the rolling friction.
As a matter of interest, further solutions have, for quite a while now, already been realised. Our tyres:
1. are getting wider and wider, 2. now have a slightly greater outside diameter, 3. now have a much greater inside diameter, 4. are given shorter and partly also stronger side-walls.
Apart perhaps from point 1., these are the measures, which have improved the rolling resistance of tyres. 10/12