The maxxis crossmark 650b 275 folding xc mountain bike tyre represents dramatic evolution of the cross country racing tire the maxxis crossmark features an almost continuous centre ridge that flies on hardpack however it still possesses enough spacing to get purchase on wet roots and rocks the exception series of tires is a combination of maxxis 62a compound and their 120 tpi casing this not only makes for a lighter model tire but it also enhances cornering braking and acceleration t