The Michelin-sports 4S* (PS4S*) tires will be fitted to BMW's new X3 M and X4 M models and will be the only designated accessories available worldwide. The BMW X3 M and X4 M Competition models are equipped with 21-inch light alloy wheels and will be equipped with Michelin PS4S*255/40ZR21 102Y front wheels and 265/40ZR21 105Y rear wheel ultra-high performance tires. These tires are available in a number of Michelin technologies, including a tread pattern with multiple formulations and an aramid-reinforced carcass design. The star (*) stands for the original tires certified by BMW Technology.
Michelin maintains a long-term relationship with the BMW M Series. PS4S* tires are the result of collaborative research and development in the past three years. A total of approximately 800 prototype tires and 1,400 pre-production tires were tested at the test sites in Nürburgring, Germany, Miramars and Ladu, France to ensure that the performance characteristics of the tires met the requirements of BMW engineers.
During the development period, engineers of the BMW M-Series models required Michelin to focus on the balance of dry performance, high grip, long-lasting track performance and wetland performance while retaining the sporty character of driving. The size of the front and rear wheels is similar, meaning that Michelin can only adjust its different characteristics through tread pattern and rubber formula to meet the design requirements.
Among the tires provided by Michelin, the front wheel adopts triple compound formula technology and the rear wheel adopts double compound formula technology. The compound formulation technology was originally designed for rally tires, using different rubber formulations on different parts of the tread to precisely adjust the performance of the tire. For example, the outer shoulder provides excellent grip and wear resistance when cornering; the middle rib is optimized for steering and handling; the internal shoulder is specially designed to allow the tire to break through the water film and maintain grip on the wet ground . The combination of these technologies helps the Michelin PS4S* achieve a unique balance of grip, comfort, safety and driving pleasure, meeting the stringent standards of the BMW M-series and for everyday road use. The BMW X3 M and X4 M owners enjoy the driving experience with the Michelin PS4S* tires.