The crusade pdx portland39s airport code is named after portland39s famous cross crusade the largest participant cyclocross series in the world pdx tread is designed to roll fast on hard pack mud and to really bite and stick in the corners regardless of the weather the center tread is aligned lower than the side edge to create fast roll on hard pack and road whatever the weather outside tread offers superior edge control so your bike stays under you in the curves and the leading edge