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
Wheel construction Wheel construction Wheel construction refers to the making of wheels. Construction of wire-spoked wheels is generally termed as wheelbuilding, so wheel construction refers to construction of non-wire wheels, e.g. wheels of cars and other heavier vehicles. Wheels are constructed in a wide variety of designs using different materials, but in the early 21st century, aluminum and steel are most often used, with steel-made wheels being heavier and more durable than aluminum wheels. The performance of a wheel depends on the alloy and technique used to construct it. A wheel is usually made up of a rim, which connects with the