Moyeu

Moyeu is a French term meaning the hub or central rotating assembly of a wheel. In mechanical engineering, the moyeu (hub) is the component that connects the wheel to its axle and hosts the bearings, letting the wheel rotate while transmitting load from the vehicle to the axle. The hub typically integrates an axle, bearings, and a hub shell, and may include a drum or disc brake mounting in some designs.

In bicycles, the moyeu is the central part of the wheel that houses the bearings, accepts the axle, and serves as the mounting point for the spokes via flange holes. The rear moyeu may include a freehub body or freewheel mechanism to drive the sprockets, while the front moyeu does not.

Two common bearing arrangements are found in moyeux: cup-and-cone bearings, which are user-serviceable but require maintenance, and cartridge bearings, which are sealed and replaceable. Modern hubs may use through-axle interfaces, bolt-through axles, quick-release skewers, and standardized widths (for example, 100 mm front and 135 mm rear in traditional road spacing, with newer through-axle standards). Hubs are typically made of aluminum or steel, with high-end versions using lightweight alloys or carbon components and sealed bearings for durability.

In addition to bicycles, the term moyeu is used in other wheeled applications to denote the wheel center, such as in carts, skateboards, and machinery.