Bicycle wheel metal or carbon fiber rim which holds a pneumatic rubber tire. A hub is the center part of a bicycle wheel. It consists of an axle, bearings and a hub shell. The hub shell typically has two machined metal flanges to which spokes can be attached. Hub shells can be one-piece with press-in cartridge or free bearings or, in the case of older designs, the flanges may be affixed to a separate hub shell. The axle is attached to dropouts on the fork or the frame. The axle can attach using a: Modern bicycles have adopted standard axle spacing: the
Hubcap decorating one car with the wheel covers from another was common. Two very desirable wheel covers were those of the 1950 Cadillac (called the "Sombrero") and that of the 1953 to 1955 Oldsmobile, which resembled a huge, three-tined spinner. Aftermarket suppliers included the "Mooneyes" brand (named after the firm's founder Dean Moon) hubcaps and wheel covers that were some of the first independently offered for hot rods and custom cars. Another variant of the wheel cover, known also as "wheel shrouds" or "rim blanking", is that commonly associated with the German wheelmaking brand BBS since the 1970s. These are attached