On the front 245/35 ZR 19 and at the back 265/35 ZR 19 tyres, why are the tyres different sizes?
With the M2 CS, as with other rear-wheel drive BMW M vehicles, we’re talking about high-performance automobiles with an extremely high performance level. To do justice to the performance, the rear tyres are wider than the front, as they have to transmit both the driving and lateral forces.
Do wider tyres automatically mean better traction?
Put simply, yes – with the same tread and the same compound compared to a narrower tyre, as they increase the contact of the rubber surface on the ground. But only going on the size, without taking the tread and the rubber into account, would be wrong. Rim width and tyre contour also influence the traction and are important parameters.
With such a dynamic high-performance vehicle with a short wheelbase like the M2 CS, how does one get comfort in everyday driving and perfect directional stability?
Thanks to the fast response from the tyres and the corresponding feedback from the axles, the driver has a constant response from the driving surface. Thus, drivers can react to the smallest disturbance. With unmatched tyres, even combined with a perfect suspension, there will be a delay in reaction, including the car’s response after a steering command driving error or a correction by the driver. This leads to a subjective feeling of bad directional stability, because it is not enough to keep hold of the steering wheel – one will also be forced to keep making corrections. Here too, the tyre plays an essential part, but this should always be seen in the context of the interplay between tyre and suspension.