From Wikipedia, the free encyclopedia
A cyclo-cross bicycle is a bicycle specifically designed for the rigors of a cyclo-cross race. Cyclo-cross bicycles roughly resemble the racing bicycles used in road-racing. The major differences between the two are the frame geometry and the wider clearances that cyclo-cross bikes have for their larger tires and mud and other debris that they accumulate.

Frame design

Frame materials are selected with an aim to produce a lightweight, yet stiff and responsive frame. Lightness is prized for ease of carrying while running. A cyclo-cross racer may have lifted or carried his bike as many as 30 times in one 60 minute race, increasing the need for a lightweight bicycle. Aluminum frames were popular long before they became commonplace on the road. Today the most popular material is aluminum with carbon fibre being popular at a professional level and steel and titanium being favorites amongst those searching for a smoother ride and a longer lasting frame.

Cyclo-cross frames require clearance for slightly fatter (generally 30-34 mm) tires and the debris and mud that is picked up by them. They are typically very simple, often eschewing bridges between the rear stays. Other features that combat build-up of mud are top tube (rather than bottom bracket) routed derailleur cables. Some specialist cyclo-cross bikes also have a higher bottom bracket to aid clearance over rough ground; extra clearance could prevent toe clips from dragging while re-mounting after an obstacle. This is less and less common as clipless pedals have become the norm for cyclo-cross.