User:Robert Merkel/Gravel bicycle

A gravel bicycle is a type of bicycle intended for riding on gravel or dirt roads.

While bicycles have been used for riding on such roads since bicycles were invented, the "modern" gravel bicycle, as a category, evolved in the 2010s, adopting technology from road racing bicycles, cyclocross bicycles and mountain bikes.

Design characteristics
Gravel bicycles generally use drop bars, similar to racing and cyclocross bicycles, unlike mountain bikes and hybrid bicycles. Many gravel bikes are fitted with wider bars than would be typical for a road or cyclocross bike, and a few have been fitted with "flared" bars that angle outwards (need image).

Unlike cyclocross bikes, which are designed exclusively for 700c wheels and a maximum tyre width of around 33 mm (still wider than a typical racing bike tire of 28mm), gravel bikes are designed to fit much wider tires, often around 40mm but sometimes up to 45-50mm. Mountain bikes run wider tyres still. Some gravel bikes are fitted with 650b wheels, whose smaller diameter allows wider tyres to be fitted to a similarly configured frame. Like mountain bikes, the vast majority of gravel bikes use tubeless tires, as they are far less susceptible to punctures and pinch flats than clincher tires.

Gravel bikes have frame geometry that is intermediate between a road bike and a cross-country mountain bike, leading to a bike that is slower to turn but more stable, particularly in low-traction descents, than a road bike or cyclocross bike.

Gravel bikes almost universally use disc brakes, and most use hydraulic discs.

The majority of gravel bikes do not have mechanical suspension, unlike mountain bikes, though a few such bikes are being offered by major manufacturers. Even gravel bikes with suspension have far less suspension travel than a typical cross-country mountain bike.

Gravel bikes often have additional mounting points for bottle cages, as well as carriage points optimised for carrying bikepacking gear.

Groupsets
The drivetrains for mountain bikes are mostly supplied by the three major groupset manufacturers, Shimano, SRAM, and Campagnolo, and, like other aspects of gravel bikes, offer a blend of characteristics from road and mountain bicycles.