The Wheel Disc when referring to a wheel that accepts a disk brake, is common on cars, trucks, motorcycles, and bicycles. A disk wheel that refers to a wheel with no spokes or openings that air can pass through is common on certain race cars as well as on racing bicycles. Wheel Disc may refer to a type of wheel that accepts a disk brake, or it may refer to a wheel built as a disk which has no spokes or openings that air can pass through.