Prototype Nokian Tyre Demonstrates Positive Rolling Resistance Qualities

A prototype summer tyre developed by Nokian Tyres is said to have demonstrated 64 per cent superior rolling resistance against a premium ‘eco’ tyre in testing conducted by the Finnish tyre maker. In a test held on March 9, a Toyota Prius was fitted with the prototype tyres and also with Michelin Energy Saver tyres (both the same dimensions and pressure) and rolled down a ramp in neutral gear in windless conditions. As Nokian explains, the distance the car rolled corresponds directly with the tyres’ rolling resistance – the further the car rolls, the lower the rolling resistance. Nokian reports that the car managed to roll 129 metres when fitted with its prototype tyre, while it stopped after 78.9 metres when fitted with Energy Saver tyres.

“Our tyre of the future nearly reaches the best EU fuel efficiency class A and consumes considerably less than the best passenger car tyres of today, which are two classes worse and only get class C,” said Teppo Huovila, vice president of R&D with Nokian Tyres. “Nevertheless the prototype offers a normal level with all other features.”

In addition to safety features, tyre product development will, in the coming years, focus more and more on lowering the rolling resistance. “Tyre material development actively searches for new improving possibilities,” Huovila added. “Up and coming are, among others, the next generation silica compounds and steel belt structures. They emit less heat during the deformation of the tyre and consequently lower the tyre’s rolling resistance. In 2015, the best passenger car tyres will probably further decrease fuel consumption by five per cent compared to the best of today’s tyres without compromising on the current safety features.”

At the moment, states Nokian, the rolling resistance of the best passenger car tyres corresponds to grade C of the EU new grading system, but the majority of today’s tyres belong to grades G, F and E. In practice, moving from one grade to the next means a decrease in fuel consumption of approximately two to three per cent. “The product development and manufacture of such a tyre are very challenging processes. Very precise structures, smaller tolerances and the newest special materials are required. All features must be on a good level in the tyre; as a responsible manufacturer, we can never focus on improving just one feature at the expense of others,” Huovila added.