Most road bikes use calliper brakes, though recently more sportive and endurance geometry bikes have been built with disc brakes – which are more effective in the wet and allow for a lighter rim.

In the case of calliper brakes, the rim braking surface is usually aluminium, or carbon. Aluminium rims offer smooth, quicker stopping and can be used with standard brake pads made from rubber. Though light, aluminium rims will be much heavier than carbon.

Carbon rims are generally found on road bike wheels designed for competition or competitive riders looking to achieve a quick time on a hilly sportive. These rims are much lighter, and have a gorgeous ride quality that feels smooth and fast rolling. The flaw in this seeming perfection is that the rims require the use of carbon friendly brake pads, made from a rubber and cork mix – stopping power is adequate, but not as quick, especially in the wet.

Some carbon deep section wheels to use a predominately carbon rim, with an aluminium braking surface or treatment – giving the best of both worlds, with a small weight sacrifice. Mavic’s ever popular Cosmic Carbone wheels are an example of this approach.

Carbon rims are also more fragile than their cheaper but heavier aluminium alternative, so they are best kept for summer use, and ‘special days out’ than used as a day-to-day wheel.