A street circuit with cult character Bumpy and narrow street circuit a challenge for drivers and brakesHankook slick tyre supports precise handling at selective circuitFor many motorsport fans, the Norisring in Nuremberg is cult, and this weekend, the circuit has a reason to celebrate: with the DTM event, the legendary street circuit is hosting an extraordinary racing event for the 70th time. Back in 1947 already, motorcycles were racing at the 2.3 kilometres long track. Ever since, the public roads around the concrete grandstand at the Dutzenteich are being turned into a circuit every year with additional grandstands being installed for the occasion. In any case, the fifth season round of the most popular international touring car series guarantees thrilling racing action at the hot asphalt in Nuremberg. The organising Motorsport Club Nuremberg is expecting 140,000 spectators in the “German DTM Monaco”.The DTM drivers are also enjoying the unique atmosphere at the Norisring, but they have to adapt to surprises time and again. After all, normal traffic is usually using the streets in the heart of Nuremberg, with all its wearing effects. The road surface changes all the time, new bumps are coming up every year, just like patches where the asphalt had to be repaired.With officially eight corners, the track lay-out not seems very demanding at first sight. But reality is different. No other DTM circuit is so hard on the brakes as Norisring. For instance, before the first hairpin after the start, drivers have to slow down from 245 km/h to approximately 40 km/h. Here, the right balance in the car is an important factor for victory. The wall along the back stretch at the exit of the Schöller-S has caught out numerous drivers already, with a substantial number of rear-view mirrors traditionally being torn off. At the very narrow DTM circuit, the shortest in Germany, thousandths of a second are decisive, a slight error can already terminate the race.
For instance, drivers have to stick to the racing line throughout the race. “Anyone who comes off only a few inches comes into the dirt which was produced by the road traffic and will hit trouble”, says Manfred Sandbichler, Hankook’s Motorsport Director Europe. The many bumps are making the cars unstable, which could affect the handling under braking. “Here, the teams can work with low tyre pressure to make the cars stick to the track. Moreover, an asymmetric set-up is required, because the direction of the circuit is almost totally anti-clockwise and there is more load on the right-hand side of the cars because of the centrifugal forces”, says Sandbichler.Neither the changing road surfaces nor the forecast high temperatures are a problem for the Hankook competition tyres. Manfred Sandbichler: “With its high consistency, the Ventus Race allows for very long and fast stints. Its precise handling helps the drivers finding the right line at this narrow and selective track.”And as the Hankook competition tyres are being produced entirely without carcinogenic high PAH oils, there has been no harmful tyre abrasion anymore since Hankook entered the DTM.
Competition tyres know-howThe competition tyres look very much similar to their road-legal counterparts, but their construction and compound is significantly different. Which are the particularly important components and their difference compared to road-legal tyres with respect to the particular requirements of the tracks during the 2012 DTM season?Norisring: Tyre contourThe tyre contour is the outside shape of the tyre. It has its effect on the handling in every condition (wet/dry). For competition tyres, comfort is irrelevant. The focus is on performance and handling. These are being achieved, among others, by a rigid side wall construction with an edgy shoulder and a very flat surface. Road-legal tyres have a more round surface contour with a bulbous side wall in order to achieve a more comfortable ride and smooth handling.
