Xking our all purpose weapon its developers say it can do anything its riders say that39s my tyre super fast but nevertheless with a good grip the x king was developed with the topeak ergon mountain bike professional team despite pronounced studs the x king rolls off smoothly and very quietly no matter if you are on your own or in a team with race and mountain king the super light x king easily covers many uses ranging from cross countryrace to alpcross the x king simply l