Tyre manufacturer Goodyear’s Eagle F1 Asymmetric 2 235/40 R18 956 XL is the only tyre approved for use on automotive manufacturer Ford’s Focus ST automobile, owing to its ultrahigh- performance (UHP) qualities.

“The Eagle F1 Asymmetric 2 tyre has earned a string of awards, positive reviews and top competitor test results globally since its international launch in Europe in 2011,” Goodyear group public relations manager Lize Hayward tells Engineering News.

She adds that this tyre has been sold in South Africa since mid-2012 and has had positive sales figures to date.

Hayward says the company is proud that the tyre has been chosen by some of the most admired car marques worldwide, including automotive manufacturers Porsche’s Carrera 911 and Ford’s Focus ST.

The Eagle F1 Asymmetric 2 tyre features active braking technology, which uses a three-dimensional block design in the tread to increase the tyre’s contact with the road when braking.

Hayward highlights the active braking tech-nology in the Eagle F1 Asymmetric 2 tyre, whereby the blocks in the tread expand under the higher load caused by braking.

“This increases the tyre-to-surface contact area, while conventional tyre blocks will not exhibit transformation during braking. This increased surface patch also offers increased grip, which, in turn, leads to shorter stopping distances being achieved by the Eagle F1 Asymmetric 2 tyre,” she highlights.

“The control and breaking performance of the Eagle F1 Asymmetric 2 tyre, which has been demonstrated repeatedly in independent benchmarking tests, is a critical factor for demanding drivers of sports cars,” Hayward asserts.

Further, she adds that the tyre was designed to meet low carbon dioxide emission requirements.

“Goodyear’s fuel-saving technology, which is integrated into the Eagle F1 Asymmetric 2 tyre, assists with lower rolling resistance and vehicular emission reductions, as the technology is driven by reduced tyre weight and the use of a new ‘high surface’ silica grade, which contribute to reduced heat generation,” Hayward points out.

Challenges

There are key differences between a UHP tyre and a standard tyre, notes Hayward.

“During the development of a standard tyre, Goodyear focuses on developing a tyre that delivers value for money and offers a comfortable journey, with high levels of wet grip for smaller vehicles,” she states.

Hayward explains that when the company develops a UHP tyre, however, it aims to develop a tyre for powerful cars that delivers high performance in safety-relevant areas at higher speeds and in various conditions.

She says UHP tyres differ from standard tyres in numerous ways, as the compound used to manufacture the UHP tyre, its structure and often its size differ from standard tyres.

“The compound used in a UHP tyre, such as the Eagle F1 Asymmetric 2 tyre, often derives many characteristics from racing compounds. It may contain a higher grade of silica and traction resins, which are not found in the compound of standard tyres,” explains Hayward.

Moreover, she highlights that the Eagle F1 Asymmetric 2 was developed with a new, more rigid crossed-piled carcass structure, while standard tyres usually use a 90º ply angle. The Eagle F1 Asymmetric 2 has a lower ply angle, which contributes to increased torsion stiffness and delivers improved steering precision, handling and braking on dry road surfaces.

Other Benefits

Hayward believes there are many benefits of using UHP tyres, especially for drivers who require efficient handling capabilities for their powerful vehicles on dry and wet roads.

“These drivers require maximum grip; therefore, they require top-performing tyres for a sporty drive,” she emphasises.

Additionally, UHP tyres will serve drivers of heavy and powerful family and business vehicles who want to be prepared when they are required to manoeuvre particularly well at high speed.

“These drivers think about safety first and demand tyres with the highest levels of safety in all driving and road conditions,” she says, adding that Goodyear’s Eagle F1 Asymmetric 2 tyre has been specifically developed to deliver improved performance on safety parameters such as shorter braking distances in wet and dry conditions.

Testing Procedures

Hayward states that all Goodyear tyres are put through a series of tests, which include brak-ing and handling on dry and wet surfaces.

The testing of heavy-circuit handling on multiple circuits, each designed with its own set of challenges, enables Goodyear to test the tyre under extreme driving conditions.

Goodyear tested the Eagle F1 Asymmetric 2 tyre to ascertain the tyre’s heavy-handling capacities at its test tracks in France and in Luxembourg. The tyre was also tested for its high-speed durability at a high-speed test track, the Nardò ring, north-west of the town of Nardò, in Italy.

“The Eagle F1 Asymmetric 2 was also tested in Spain and in North America, as well as at the Nürburgring Nordschleife racetrack, in Germany, which comprises 73 corners, an 18% ascending gradient and an altitude difference of 290 m, along with 20.8 km of mountain and valley driving, including different types of asphalt,” explains Hayward.