Not to be confused with Roadster (bicycle)
A road bicycle is a synonym for the term racing bicycle. It is also used less formally for any bicycle designed for use primarily on paved roads, as opposed to off-road terrain. In general road bicycles have drop handlebars and multiple gears, although there are single and fixed gear varieties.
A racing bicycle is a bicycle designed for road cycling according to the rules of the Union Cycliste Internationale (UCI). The UCI rules were altered in 1934 to exclude recumbent bicycles. Racing bicycles are also commonly known as road bicycles.
The most important things about a racing bicycle are its light weight and the aerodynamic efficiency and ergonomics of the rider’s position. To this effect racing bicycles may sacrifice comfort for speed. The drop handlebars are positioned lower than the saddle in order to put the rider in a more aerodynamic posture. The front and back wheels are close together so the bicycle has quick handling. The derailleur gear ratios are closely-spaced so that the rider can pedal at his or her optimum cadence.
A hybrid bicycle is a bicycle designed for general-purpose utility or commuter cycling on paved and unpaved roads, paths, and trails. Also known under such names as City bike, Cross bike, or Commuter, the hybrid takes design features from both the road bike and mountain bike, with the goal of making a bike for general commuting and transportation.
In general, hybrids use the mountain bike’s triple crank, together with the latter’s handlebars giving a more upright posture than road bicycles. They also usually use one of the kinds of brakes used on mountain bikes, namely linear pull, or disc. From the road bicycle they take the 700C (larger) wheel diameter for higher speeds, but use a wider rim and tire for increased strength.
Different variations of the hybrid bicycle exist. As a category more defined by what it is not than what it is the lines between the variations are ambiguous, but they can be classified by the design goals. There are hybrid bicycles optimized for commuting, for use in urban environments, or for use on a variety of paved and unpaved road surfaces. For some bicycle manufacturers, differences in hybrid type or nomenclature have more to do with marketing focus rather than design and specification, though specific features of certain hybrid bikes may suit one need better than another.
The so-called cross bike utilizes a road bicycle frame similar to a racing or sport/touring bicycle, and is normally equipped with nearly flat handlebars to provide a more upright riding position than a racing or sport/touring bike. As a hybrid bike intended for general recreational and utility use, the cross bike differs from the cyclo-cross bicycle, which is a high-end racing bicycle purposely designed to compete in the sport of cyclo-cross competition. Cross bikes are fitted with 700C wheels using somewhat wider semi-treaded tires (1.125 – 1.25 inches, or 28-32 mm) than those fitted to most racing or sport/touring models. The additional tire width and tread is intended to give the cross bike hybrid some ability to deal with rough or littered surfaces that might be encountered on paved or unpaved bike trails, such as gravel, leaves, hard-packed sand, and shallow mud. Most cross bikes are biased towards moderate off-pavement use and light weight, and as such are not normally fitted with fenders, lights, or carrier racks. The larger 700C wheels are a little faster on paved surfaces and can give an advantage for longer trips or for touring purposes.
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 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.
The commuter bike is a hybrid designed specifically for commuting over short or long distances. It typically features derailleur gearing, 700C wheels with fairly light 1.125-inch (28 mm) tires, a carrier rack, full fenders, and a frame with suitable mounting points for attachment of various load-carrying baskets or panniers. It sometimes, though not always has an enclosed chain guard to allow a rider to pedal the bike in long pants without entangling them in the chain. A well-equipped commuter bike typically features front and rear lights for use in the early morning or late evening hours encountered at the start or end of a business day.
Hybrid City Bike
Similar to the commuter bike, the city bike is optimized for the rough-and-tumble of urban commuting. The city bike differs from the familiar European city bike in its mountain bike heritage, gearing, and strong yet lightweight frame construction. It usually features mountain bike-sized (26-inch) wheels, a more upright seating position, and fairly wide 1.5 – 1.95-inch (38 – 50 mm) heavy belted tires designed to shrug off road hazards commonly found in the city, such as broken glass. Using a sturdy welded chromoly or aluminum frame derived from the mountain bike, the city bike is more capable at handling urban hazards such as deep potholes, drainage grates, and jumps off city curbs. City bikes are designed to have reasonably quick, yet solid and predictable handling, and are normally fitted with full fenders for use in all weather conditions. A few city bikes may have enclosed chain guards, while others may be equipped with suspension forks, similar to mountain bikes. City bikes may also come with front and rear lighting systems for use at night or in bad weather.
Another subclass of the hybrid category is the comfort bike. Comfort bikes are essentially modern versions of the old roadster and sports roadster bicycle, though modern comfort bikes are often equipped with derailleur rather than hub gearing. They typically have a modified mountain bike frame with a tall head tube to provide an upright riding position, 26-inch wheels, and 1.75 or 1.95-inch (45 – 50 mm) smooth or semi-slick tires. Comfort bikes typically incorporate such features as front suspension forks, seat post suspension with wide plush saddles, and drop-center, angled North Road style handlebars designed for easy reach while riding in an upright position. Some comfort bikes are fitted with Hub gears instead of derailleur gears.