In mountain bike sports the tyres play a central role. The quality of the tyres is decisive, particularly in demanding terrain and on difficult trails, and whether the rider has good control over the bike or not. The innovative Schwalbe Procore dual chamber system ensures maximum performance of and control over tyre pressure. The well-conceived idea of the dual chamber system implies differentiated distribution of air into the tyres according to preference and terrain condition. This is achieved by the core chamber of the tyre being fillable with high pressure of around four to six bars for extremely high shock absorption and excellent emergency running properties, and the outer chamber allowing the pressure to be reduced to only one bar. In combination, this means that the outer chamber can be driven with extremely low pressure for enormously improved tyre performance. A central role in this system of optimised pressure is played by a patented dual valve that distributes the air into both chambers. The upper part of the valve is a selector which is simply screwed in or out to individually fill the desired chamber. An additional “air-guide” integrated over the valve then allows air to enter into the outer chamber. The result of this new tyre concept is that it allows mountain bikers to ride much lighter tyres even in hard use conditions, thanks to a sophisticated design and user-friendly functionality.