Definition
A bicycle wheel is a circular component of a bicycle that consists of a rim, spokes, hub, and tire, and is designed to rotate around an axle to support the bicycle’s load and facilitate motion.
Overview
Bicycle wheels are integral to the function of bicycles, converting rider input into forward motion while providing stability, shock absorption, and steering control. Modern bicycles typically employ two wheels—front and rear—each mounted on a fork or frame via a hub axle. Wheel sizes vary according to bicycle type, ranging from 12 inches for children's models to 29 inches for mountain bikes, with the most common adult road and hybrid sizes being 700 C (approximately 28 inches) and 26 inches.
Etymology/Origin
The term combines “bicycle,” derived from the French bicyclette (itself from bi- meaning “two” and cycle meaning “circle”), and “wheel,” from Old English hwēol meaning “circular object that turns.” The compound “bicycle wheel” first appears in English-language publications in the late 19th century concurrent with the popularization of the safety bicycle.
Characteristics
| Feature | Description |
|---|---|
| Rim | The outer hoop, usually made of aluminum alloy, carbon fiber, or steel, to which the tire is mounted. Rims may be clincher, tubular, or tubeless-ready. |
| Hub | Central rotating assembly containing bearings, axle, and flanges for spoke attachment. Hubs can be front (steering) or rear (driving) and may incorporate gear cassette bodies, disc brake mounts, or motor units for e‑bikes. |
| Spokes | Thin rods, commonly made of stainless steel or galvanized steel, connecting the hub to the rim. Lacing patterns (e.g., 3-cross, 2-cross) affect wheel strength and tension distribution. |
| Tire | Rubber component mounted on the rim, either with an inner tube (clincher or tubular) or tubeless. Tire width, tread pattern, and pressure rating influence ride characteristics. |
| Diameter and Width | Measured by ISO/ETRTO sizing (e.g., 622 mm bead seat diameter for 700 C). Width varies from narrow road tires (≈23 mm) to wide mountain tires (≈2.5 in). |
| Weight | Influenced by material selection and design; high-performance wheels can weigh under 1 kg, while robust mountain bike wheels may exceed 2 kg. |
| Aerodynamics | Rim profiles (deep section, aerodynamic shapes) reduce drag, particularly important for road and time‑trial bicycles. |
| Durability and Maintenance | Regular inspection of spoke tension, hub bearings, and rim integrity is required. Wheels may be trued (aligned) using a tensioning spoke wrench. |
Related Topics
- Hub – The central component of a wheel that houses bearings and interfaces with the axle.
- Rim (bicycle) – The outer edge of the wheel that holds the tire.
- Spoke – Rods that transmit tension from the hub to the rim.
- Tire (bicycle) – The rubber outer covering that contacts the ground.
- Bicycle Frame – The structure to which wheels are attached, providing overall geometry and stiffness.
- Disc Brake – A braking system that may mount to the hub or rotor, affecting wheel design.
- E‑bike Motor Integration – Systems where the motor is incorporated into the hub, influencing wheel specifications.
- Wheelbuilding – The craft and engineering practice of assembling and truing bicycle wheels.