Pirelli Launches the Winter Sottozero Serie II

The latest evolution of Pirelli’s performance winter tyre has been unveiled at the Swiss ski resort town of Zermatt. The Winter Sottozero Serie II, a tyre the Italian manufacturer states will meet the needs of the most demanding drivers by adapting to conditions typically encountered during the autumn and winter months, has been released in two distinct performance versions: the W210/W240 for high performance cars, and the even more extreme W270 for super sports models. Pirelli reports that Porsche, Maserati, Lamborghini, Ferrari, BMW, Bentley, Aston Martin and Alfa Romeo have already homologated the new Sottozero as original equipment.

“Despite global warming, winter is still here,” commented Pirelli Tyre CEO Francesco Gori at the Sottozero Serie II launch in Zermatt. Mr. Gori however emphasised that a change in thinking has taken place at Pirelli in response to recent climatic trends, along with changes in automotive technology and European regulations. The new tyre was thus designed not just for regions receiving significant winter snowfall; rather it is a tyre for low temperature conditions. Today’s more unpredictable weather conditions, says Pirelli, with dry spells when snow is traditionally expected, and sudden heavy rainfall in the late winter or at the beginning of autumn, means a need has arisen for the development of versatile tyres guaranteeing safety not only on snow and ice, but also on wet or slushy surfaces when temperatures fall below 7 degrees, a temperature that alters both the road surface and the behaviour of a tyre.

Both the W210-W240 and W270 versions of the Winter Sottozero Serie II feature compounds free from aromatic oils, and thus already comply with European standards coming into effect in 2010. New more eco-friendly polymers and mixing processes have also been used in the compounds of both tyre versions, Pirelli reports this has been done without altering performance and safety characteristics. The compounds used in the Winter Sottozero Serie II also utilise Pirelli’s TDC (Temperature Dynamic Compound) technology, which the tyremaker claims combines and optimises the features of compounds for wet surfaces and for ice, giving improved performance on wet roads at all the usual winter temperatures, i.e. those around zero degrees Celsius. Furthermore, the the new tyre features a tread Pirelli says has been designed to improve performance and safety in terms of aquaplaning, lateral grip on snow or dry roads, grip and braking on snow and handling on dry surfaces.

For the higher performance W270 version, Pirelli says its technicians have adopted a number of additional innovations, such as a dual compound and flexible side strips, and they have drawn upon the UHP technology used in the P Zero; this is the first time, claims Pirelli, that such technology has been incorporated into a winter tyre. The W270 features the P Zero Pirelli internal structure and band, giving similar performance in terms of driving pleasure, sensitivity and safety. The compound used is a Pirelli patended dual compound consisting of a softer compound in the outer area – which Pirelli says guarantees ‘typical tyre performance’ – and a harder compound in the inner area intended to increase safety at high speeds. In practice, the combination of the two compounds, comments Pirelli, gives excellent handling on dry surfaces and maximum performance on snow, leaving safety parameters unaltered. Tests conducted by Pirelli indicate that, compared with the previous series Sottozero, the W270 delivers the strongest improvements in the area of dry stability, with improvements also occuring in dry braking, wet handling, wet braking, slush and aquaplaning.

At present the Winter Sottozero Serie II is available in 36 sizes for 15 to 20-inch rim diameters, T to W speed ratings and 30 to 65 aspect ratios. “It covers more than 80 per cent of the top performance winter market,” stated Mr. Gori. “Furthermore, we would like to introduce the same sizes for run-flat tyres, especially for BMW.” Prices for the new Sottozero will vary from market to market, however the Pirelli Tyre CEO indicated a set would approximately cost 600 euros for cars such as the Audi A3, 900 euros for Mercedes C-Class and similar vehicles, while prices for higher performance vehicles such as the Bentley Continental GT would be in the vicinity of 2,000 euros per set.