Cyclo-cross bicycle

Frame design

Frame materials are selected with an aim to produce a lightweight, stiff 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.

[edit] Components

Surly Crosscheck cyclo-cross bicycle with Campagnolo groupset and a single chainring

Cantilever brake bosses are mounted with the traditional design of brake preferred to V-brakes, again to prevent clogging with mud. Wheels are of the normal road racing type fitted with knobbie tires (a variety of tread designs in both tubular and clincher types are available), and gearing is a little lower. There are also slight geometry differences between the two; cyclo-cross bikes tend to have slightly higher handlebars for a more upright position as aerodynamics have little importance in a cross race. A second set of brake levers on the tops, called top mount brake levers, are favored by some competitors. In general, with a change of tires and gearing a cyclo-cross bike can double as a perfectly adequate road racing machine. However, most cyclo-cross racers prefer clipless mountain bike pedals for their easy dual-sided entry and mud-shedding abilities. Also, the mountain bike shoes used with them provide better traction whilst running than a typical road style shoe thanks to grip and flexibility in the sole. Gearing is typically lower, with most common setups using a 46-38 chainring combination with a 12-27 cassette cluster.

Choices of equipment tend more towards the idiosyncratic than in road racing; for example single-speed bicycles also have some popularity due to the advantage of mechanical simplicity in the often very muddy conditions and the fringe nature of the sport. Some riders opt to use a single chainring in the front (typically a 40-42 tooth chainring) while retaining gears in the rear cassette. This has some of the advantages of the single-speed: the weight of the front derailleur and the front shift lever are lost, fewer mechanical problems arise (there is less danger of the chain falling off), and racing is psychologically simpler.