The changing of the seasons, despite the fact that some people insist it no longer exists, represents those short, delicate parts of the year when big changes is the temperature signal the end of one season and the beginning of another, often causing issues for tyre performance due the variations in conditions met. If you use all season tyres, also known as all weather tyres, this problem will seem relative, but the process of changing from summer to winter tyres and back again is crucial in terms of safety for the majority of drivers, as well as for conforming to driving regulations.
How do all season tyres work
All season tyres can be seen as a compromise between summer and winter tyres, given their versatility. And in areas where the temperature is milder for most of the year, all season tyres can be a good choice for a variety of reasons. However, even though all season tyres can be used in both summer and winter, as their average resistance means good road control in various weather conditions and good grip even on blanket snow, if you take, for example, the Cinturato All Season marked with the 3MPSF logo (the symbol of three mountain peaks with a snowflake, given for compounds which produce excellent performance at low temperatures under specific conditions), their performance can never compare with summer or winter tyres in their respective ideal conditions. During either warmer or colder weather, summer or winter compounds provide an extremely high level of grip. So if you want the highest possible performance throughout the year, the best tyres are the ones which have been developed to deal specifically with warmer or colder weather.
Characteristics of summer tyres
Summer tyres are immediately recognisable from the compounds used to make them. Their structure is more rigid and compact, because of the need to resist higher temperatures during hot weather. The range of products include tyres with flat profiles and typically squared shoulders, designed to accommodate fast speeds and when gripping at high speeds when cornering, while there are other types of tyres with carved treads which are either symmetrical, directional or asymmetrical, depending on the design and water expulsion speed.
At temperatures of 7°C or above, this tyre type can provide full performance without being affected by high levels of heat resistance and frontal and lateral stress. On both dry and wet roads its grip is always excellent at the given temperatures, and on damp surfaces good hold is ensured by the tread design. This area is vital and needs to be checked regularly, given that if the grooves have a depth of only 4mm, they cannot provide an adequate water outflow, meaning grip can become increasingly compromised, with potentially serious consequences for safety.
When temperatures drop below 7°C, because of the more rigid structure of the tyre its behaviour radically changes. A colder climate means the summer compound cannot perform at an optimal level and, at the same time, controlling the car may be more difficult, making skidding more likely. A feeling similar to, for example, driving on a wet road with a worn down tyre. If the tyre treads are modified by excessive wear, they will not be able to expel water, preventing adequate contact with the road surface. This can lead to the risk of aquaplaning, causing a serious risk of loss of control of the vehicle. It is in any case good practice to make sure that your tyres are always in good condition, in order to avoid troublesome issues or potential danger.
…and winter tyres
For winter tyres, you can expect to find a much softer structure, even at low temperatures. This property enables these kinds of tyres to [provide consistently high performance on different types of surface, even if slippery or icy.
The fact that it is the softest tyre type available enables these tyres to quickly arrive at the ideal temperature, while at the same time remaining versatile and elastic. Below 7°C, braking distances are reduced on average by 10% on wet roads and 20% on snow, and it is with these weather conditions taken into consideration that the tread features lines, or inlays divided by deep grooves. The well-defined and carved shape comes from the lines which pass through snow and slush, ensuring the tyre can grip the terrain. And the grooves between the inlays pass out water. A winning formula that avoids the use of snow chains.
In this case two the structural conditions of the tyres are important for both their performance and their longevity, both of which are related to the vehicle and the temperature. Tyres which are too worn down and not in perfect condition will not provide effective performance. In contrast to summer tyres, winter tyres can run into trouble in temperatures above 7°C, precisely because softer compounds tend to slide or skid under the stress placed on them when exposed to high temperatures.