![Look 765 Gravel Bicycle](https://upload.wikimedia.org/wikipedia/commons/8/8c/Look_765_Gravel_Bicycle.jpg)
A gravel
bicycle
A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist.
Bic ...
is a type of bicycle intended for
gravel cycling
Gravel cycling, gravel biking or gravel grinding is a sport, or a leisure activity, in which participants ride bicycles mostly on gravel roads. Sometimes, specially designed gravel bikes are used; in other cases, any bicycle capable of cove ...
, including
gravel racing. They are also sometimes known as "adventure bicycles", particularly ones intended for harsher off-road terrain.
While bicycles have been used for riding on such roads since bicycles were invented, the "modern" gravel bicycle, as a category, evolved in the 2000s, adopting technology from
road bicycles
The term road bicycle is used to describe bicycles built for traveling at speed on paved roads. Some sources use the term to mean racing bicycle. Other sources specifically exclude racing bicycles from the definition, using the term to mean a ...
,
cyclocross bicycles and
mountain bike
A mountain bike (MTB) or mountain bicycle is a bicycle designed for off-road cycling. Mountain bikes share some similarities with other bicycles, but incorporate features designed to enhance durability and performance in rough terrain, which ...
s. They also share many characteristics of
touring bicycle
A touring bicycle is a bicycle designed or modified to handle bicycle touring. To make the bikes sufficiently robust, comfortable and capable of carrying heavy loads, special features may include a long wheelbase (for ride comfort and to avoid pe ...
s, such as relaxed geometry, wide tires and wide-range gearing.
Design characteristics
![Gravel-bike-fitted-with-aerobars-for-racing](https://upload.wikimedia.org/wikipedia/commons/8/87/Gravel-bike-fitted-with-aerobars-for-racing.jpg)
Gravel bikes have been constructed out of a wide variety of frame materials, including
aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
,
carbon fibre
Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...
,
titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ...
and
steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
. Most use
carbon fibre
Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...
forks.
Gravel bicycles generally use
drop bars, similar to racing and cyclocross bicycles, unlike mountain bikes and
hybrid bicycle
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, comf ...
s. 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. Clip-on
aerobar extensions are sometimes used, particularly in racing.
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 brake
A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc or a "rotor" to create friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hol ...
s, and most use hydraulic discs.
Gravel bikes often have additional mounting points for bottle cages, as well as carriage points optimised for carrying
bikepacking
The thumb is the first digit of the hand, next to the index finger. When a person is standing in the medical anatomical position (where the palm is facing to the front), the thumb is the outermost digit. The Medical Latin English noun for thumb ...
gear.
Suspension
The majority of gravel bikes sold to date rely on the cushioning of their wider tires, and controlled flexing in wheels, fork, and frame, to provide a cushioning effect. However, a few gravel bikes offer
mechanical suspension in some form. Where offered, the suspension travel is typically limited to about 20-30mm.
Examples of gravel bikes with suspension are the
Lauf True Grit, which has a leaf spring front fork for suspension as well as the
Cannondale
The Cannondale Bicycle Corporation is an American division of Dutch conglomerate Pon Holdings that supplies bicycles. Its headquarters are in Wilton, Connecticut with engineering offices in Freiburg, Germany. Frames are manufactured in Taiwan. ...
Topstone Carbon Lefty, which has a pivoting seat stay and flexible chainstays to provide increased suspension, and a single-sided hydraulically-suspended "lefty" front fork. Both front and rear suspension offer around 30mm of travel.
Drivetrain
![Titanium-frame-gravel-bicycle](https://upload.wikimedia.org/wikipedia/commons/7/7f/Titanium-frame-gravel-bicycle.jpg)
The drivetrains for gravel bikes are mostly supplied by the three major
groupset
A groupset or gruppo (from the Italian for "group", sometimes misspelled grouppo) is a bicycle component manufacturer's organized collection of mechanical parts. It generally refers to all of the components that make up a bicycle excluding the bicy ...
manufacturers,
Shimano
, originally and later , is a Japanese multinational manufacturing company for cycling components, fishing tackles and rowing equipment, who also produced golf supplies until 2005 and snowboarding gear until 2008. Named after founder Shozaburo ...
,
SRAM, and
Campagnolo
Campagnolo is an Italian manufacturer of high-end bicycle components with headquarters in Vicenza, Italy. The components are organised as groupsets (gruppi), and are a near-complete collection of a bicycle's mechanical parts. Campagnolo's flagsh ...
, and, like other aspects of gravel bikes, offer a blend of characteristics from road and mountain bicycles.
Unlike touring bicycles, where bar-end shifters remain quite commonly used, most gravel bicycles use integrated brake levers and shifting ("brifters") either identical to, or very similar to, modern racing bicycles.
Electronic shifting upElectronic front derailleur (Shimano Di2)
An electronic gear-shifting system is a method of changing gears on a bicycle, which enables riders to shift with electronic switches instead of using conventional control levers and mechanical cables. ...
is very common on high-end gravel bicycles.
Shimano and Campagnolo have branded families of dedicated gravel components, namely Shimano GRX and Campagnolo Ekar. SRAM does not have a dedicated gravel brand, using a mix of componentry from their mountain bike and road bike ranges.
Unlike on road bikes, where "2x" drivetrains with two front
chainring
The crankset (in the US) or chainset (in the UK), is the component of a bicycle drivetrain that converts the reciprocating motion of the rider's legs into rotational motion used to drive the chain or belt, which in turn drives the rear whee ...
s are ubiquitous, and unlike mountain bikes where "1x" drivetrains with a single front chainring are now standard on new bikes, both 1x and 2x drivetrain options are widely available for gravel bikes.
While chosen gearing depends on terrain and rider preference, it is typical for gravel bikes to offer slightly lower gearing than road bicycles.
Wheels
Gravel bike wheels are very similar to tubeless wheels used on some road and cyclocross bikes, and, indeed,
700c gravel wheelsets are often interchangeable with road and cyclocross wheelsets. 650b wheels used for gravel bikes are often derived from mountain bike wheels.
Cheaper gravel wheels usually have aluminium rims; carbon fibre is used for more expensive wheel sets. Aerodynamic shaping is used on some wheelsets to reduce drag, as on road bikes.
The main distinguishing features from tubeless road bike wheels are slightly more robust construction, and wider rim widths.
Pedals
Gravel bikes can be fitted with
clipless pedals
The pedal is the part of a bicycle that the rider pushes with their foot to propel the vehicle. It provides the connection between the cyclist's foot or shoe and the crank allowing the leg to turn the bottom bracket spindle and propel the bicyc ...
that use the
Shimano SPD or compatible cleat system, ubiquitous on mountain and cyclocross bikes.
Tires
![Schwalbe G-One gravel bicycle tire](https://upload.wikimedia.org/wikipedia/commons/2/22/Schwalbe_G-One_gravel_bicycle_tire.jpg)
Gravel bikes are able to fit a wide range of tyres, from tyres used on road racing bicycles to the narrower end of
mountain bike
A mountain bike (MTB) or mountain bicycle is a bicycle designed for off-road cycling. Mountain bikes share some similarities with other bicycles, but incorporate features designed to enhance durability and performance in rough terrain, which ...
tyres.
Unlike cyclocross bikes, which are designed exclusively for 700c wheels and a maximum tyre width of around (still wider than a typical racing bike tire of 28mm), gravel bikes are designed to fit much wider 700c tires, often around but sometimes up to . 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 tire
Tubeless tires ( also spelled as tubeless tyres in Commonwealth English) are pneumatic tires that do not require a separate inner tube.
Unlike pneumatic tires which use a separate inner tube, tubeless tires have continuous ribs molded integral ...
s, as they are less susceptible to punctures and
pinch flats than
clincher tire
A bicycle tire is a tire that fits on the wheel of a bicycle or similar vehicle. These tires may also be used on tricycles, wheelchairs, and handcycles, frequently for racing. Bicycle tires provide an important source of suspension, generate ...
s.
Tire choice is a major point of debate in
gravel racing, with riders trading off speed on sealed and high-quality dirt roads, weight, and puncture resistance and traction in dustier, sandier or muddier conditions.
References
{{reflist
Gravel cycling
Cycle types