The ski runners (6) are formed on a disc-shaped molded component (5) covering the wheel (4) rim. The runner overlaps the wheel tangentially and has a curvature (6') conforming to the wheel curvature on both sides to the front and rear. When in use the ski runner acts as a skid, and when rotated by 180 degrees into the not-in-use position acts as a mudguard and wheel protector.
