What Is the Standard Wheel Size for Racing Bikes?

Racing wheels for competitive road bikes use lightweight materials such as carbon fiber and aluminum to create a perfect marriage of strength and weight. If you're buying a new wheelset for your racing bike, it's crucial to know the size of your bike's wheels. The vast majority of racing bikes use a 700c wheel, but especially petite riders may use a frame size that can't accommodate a 700c wheel and instead use a 26-inch wheel. You can measure your wheel size before buying a new wheelset using your old wheels and a tape measure.

700c Is All Right With Me

The size of a bicycle wheel is usually measured using the tire size, which comes in several stock sizes that are universal across the world. Racing bikes use the 700c size, which has a tire bead set diameter of 622 millimeters. This wheel size is the largest available for conventional bicycles, giving a racing bike more stability at high speeds. If you're a much shorter person, your racing bike frame might not be able to comfortably accommodate 700c wheels. The smallest frame sizes offered by some manufacturers are built with 26-inch wheels, a size usually reserved for mountain bikes.

Measuring Up

Your racing wheels have other measurements that correspond to the tire size and performance. Rims used by professional cyclists for races have been getting wider, because tires in the 23- to 28-millimeter range are universally adopted over the traditional 21-millimeter racing tire. Wider tires have a reduced rolling resistance, better shock absorption and receive fewer pinch flats. This increase in rim width reduces the aerodynamic penalty for running a wider tire. Rims also have a depth measurement; carbon fiber rims will often be between 20 and 100 millimeter deep, giving the inside of the rim a wing-like shape that improves aerodynamic performance.