The continental x king racesport 650b275 folding mountain bike tyre pronounced cross king fills the gap between the race king and mountain king ii super fast yet extremely grippy the x king was developed in conjunction with the topeak ergon mtb pro team along with the basic versions in 22 and 24 widths this made in korbach racesport model come with the impressive blackchili compound with its unique combination of grip and fast rolling despite the proud tread the x king rolls