Abstract: A breathable protective filtering boot structure for a telescoping bicycle fork suspension comprises a generally cylindrical bellows-like rubber-like boot for each of a pair of fork legs which telescope along parallel vertical axes. Each boot is secured at its upper end to a male leg member and depends to form a variable volume boot chamber around the telescoping junction of the male and female leg members. The lower end of the boot has a flat annular shoulder spaced axially from and facing the top end of the female member with a cylindrical skirt depending from the boot shoulder for securing the boot to the upper end of the female leg member. A short portion of the skirt, with vent apertures between the shoulder and the female member facing away from the wheel space of the fork, encircles a small filter confining cavity at the lower end of the boot chamber.