Hybrid bike

Hybrid bicycles blend characteristics from more specialized road bikes, touring bikes and mountain bikes. The resulting "hybrid" is a general-purpose bike that can tolerate a wide range of riding conditions and applications. Their stability, comfort and ease of use make them popular with novice cyclists, casual riders, commuters, and children.

Hybrids typically borrow the flat, straight handlebars and upright seating posture of a mountain bike, which many bicyclists find comfortable and intuitive. Hybrids also employ the lighter weight, thinner wheels and smooth tires of road bikes, allowing for greater speed and less exertion when riding on the road. Hybrid bikes often have places to mount racks and bags for transporting belongings, much like a touring bike.

Hybrid bikes have spawned numerous sub-categories satisfying diverse ridership. They are classified by their design priorities, such as those optimized for comfort or fitness — and those offered as city, cross or commuter bikes.

From the early 20th century until after World War II, the utility roadster constituted most adult bicycles sold in the United Kingdom and in many parts of the British Empire. In Britain, the roadster declined noticeably in popularity during the early 1970s, as a boom in recreational cycling caused manufacturers to concentrate on lightweight (23-30 lb.), affordable derailleur sport bikes, actually slightly-modified versions of the racing bicycle of the era. In the 1980s, U.K. cyclists began to shift from road-only bicycles to all-terrain models such as the mountain bike. The mountain bike's sturdy frame and load-carrying ability gave it additional versatility as a utility bike, usurping the role previously filled by the roadster. By 1990, the roadster was almost dead; while annual U.K. bicycle sales reached an all-time record of 2.8 million, almost all of them were mountain and road/sport models. A different situation, however, was occurring in most Asian countries: roadsters are still widely made and used in countries such as China, India, Thailand, Vietnam and others as well in parts of north-western Europe.

A trekking bike is a hybrid with all the accessories necessary for bicycle touring – mudguards, pannier rack, lights etc.

Cross bikes utilize a road bicycle frame similar to a racing or sport/touring bicycle, and are 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 racing bicycle purposely designed to compete in the sport of cyclo-cross competition. Cross bikes are fitted with 700c (ISO 622) wheels wheels using somewhat wider semi-treaded tires (1.125–1.25 in or 28.6–31.8 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.

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Wikipedia