Bicycle handlebar
A bicycle handlebar is the steering control for bicycles. It is the equivalent of a tiller for vehicles and vessels, as it is most often directly mechanically linked to a pivoting front wheel via a stem which in turn attaches it to the fork. Besides steering, handlebars also often support a portion of the rider's weight, depending on their riding position, and provide a convenient mounting place for brake levers, shift levers, cyclocomputers, bells, etc.
History
The dandy horse, or draisienne, invented by Karl Drais and the first vehicle with two wheels arranged in tandem, was controlled by a bar connected to the front steering mechanism and held by the riders' two hands. The first handlebars were solid bars of steel or wood, depending on the manufacturer. Curved, moustache-shaped, drop handlebars became popular in the 1920s. Whatton bars were developed in attempt to improve the safety of penny-farthings. Handlebars made of wood, instead of steel, were used on safety bicycles to reduce weight in the 1890s. Although aluminum had been used to make bicycles as early as 1935, it was considered unsafe for handlebars until Cinelli produced them in 1963.Types of handlebar
Handlebars come in a variety of types designed for particular types of riding.Drop
Typical drop handlebars feature a straight central section attached to the stem, with each end curving first forwards and down, and then back towards the rider at a lower position. These are a very popular type of handlebar, and their exact shape and purpose leads them to be further categorised as follows.;Standard
These classic racing handlebars, as used on road or track bicycles. The bars are designed with three basic parameters; reach, drop and width. They can be further classified into three categories: classic, typically having a long reach and a deep drop, compact, featuring shorter reach and a shallow drop, and ergo or anatomic, described below. Drop bars may have one or two longitudinal indentations so that the brake and shift cables protrude less when they are wrapped under the bar tape. They may also have a flattened top section.
;Track
Image:Track Bars.JPG|thumb|right|"Track" style bars with large-radius curve
Track drop bars are a variation of bars designed for the typical riding positions of track bicycle racers. Track drops are characterized by large, sweeping ramps, effectively precluding the top and brake hood hand positions, but promoting the rider's use of the ends, or "hooks". Track bars are designed for use without brake levers, but recently experienced a surge in popularity on use with fixed gear bikes, and as such have been adapted to fit levers and hand positions.
;Ergo or anatomic
The shape of the drop may be a simple, traditional curve, or it can have a flat spot which some riders find to be more comfortable for their hands. These bars may be described as ergo or anatomic.
Some manufacturers have relegated the term anatomic to this curvature shape, while adopting the term ergo to instead describe non-cylindrical tubing cross-sections on the upper flat portion of the bar, intended to be more comfortable when riding in the upright position.
;Randonneur
Drop bars that rise slightly from the center in a shallow U, and the drop portion of the bars is set wider than the curve at the top. Designed to be slightly more comfortable than a straight drop bar for bicycles used in Audax riding. However the popularity of these bars has plummeted over the last 20 years as more and more cycle-tourists, brought up on mountainbikes, choose to use one of the 'flat' bar variations either using bar-ends or 'butterfly' bars for their holidays. However the popularity of 'gravel' bikes has seen them make a come-back.
;Drop-in
At one time, manufactures and racers experimented with drop-in bars that had an additional extension in toward the head tube at the rear end of the drops. This was intended to offer an even more aerodynamic position, due to low and narrow placement of the hands, than just the drops, while still remaining legal for mass-start races. Their popularity has since waned.
;Dirt drop
Primarily for riding off-road or on dirt, these handlebars are flared out at the ends of the handlebar. This style was used in the 1980s during the early period of mountain biking. Initially the flared portion in these handlebars was bent by hand, but now are available from manufacturers such as Salsa Cycles and SOMA Fabrications.
Bullhorn
Bullhorn handlebars, curve up and forward. They are often paired with dedicated clip-on triathlon bars when used on the road, and are also popular by themselves on track, single-speed, and fixed-gear bicycles.This style of handlebar is named after the discipline of track racing where it was originally used, and has the common nickname of "bullhorn bars" for their appearance, especially when the rider's body position is fully extended to lean forward and maintain control of the bicycle.
Improvised bullhorn bars may be constructed simply by cutting the drops off drop bars and then mounting them upside down so that the remaining start of the drop provides a slight upward hook for resting the hands, although this does not provide as much forward extension or lowering as purpose made bullhorns. These are sometimes called "flopped and chopped" or "flipped and clipped" bars, and if this is to be done, care should be taken to properly remove the sharp edges from the cuts, and to properly tape and plug the bar ends for safety purposes.
Bullmoose
The bullmoose style was common on early mountain bikes. The stem and bars are a single unit and where the single top section of the stem would be, there are instead 2 bars joined at the quill to the rear and connected to the conventional handlebar section in the front, at two off-center locations, forming a triangle. This type of handlebar is usually very large, allowing for an easy breath intake under stress. However, being heavier than contemporary flat or riser bars and being less customizeable in height and distance from the body of the rider, they progressively disappeared.Flat
Flat bars are the standard handlebars equipped on mountain bikes, hybrids, and recently on fixed-gear bicycles and flat bar road bikes. A flat bar is a nearly-straight tube, in most cases slightly bent toward the rider. Many penny-farthings and early safety bicycles had flat handlebars. The angle between the slightly swept-back ends of the handlebar and the axis of the stem clamp is known as the sweep angle.Riser
A riser is a variation of the flat bar in which the outer sections of the bars rise from the center clamp area by about 15 to 50 mm. Both flat and riser bars may be appended with bar ends, providing more hand positions.Triathlon or aero bars
Triathlon bars or aerobars include various styles of aerodynamic handlebars for racing bicycles and particularly time trial bicycles. Included are narrow, bolt-on extensions that draw the body forward into a tucked position, [|pursuit] bars that spread the arms of the rider but drop the torso into a slightly lower position, and integrated units that combine elements of both designs.Using aero bars may allow a rider to reduce time on a 40 km time trial by 90 seconds.
Triathlon bars are commonly used in triathlons and time trial events on road and track. However, they are illegal in most mass-start road races or any other event where drafting is permitted because, while aerodynamically advantageous, they tend to draw the hands away from brakes, make the rider slightly more unstable on the bike, and can be dangerous in the event of an accident. Further, they are not useful in sprints or shorter climbs where power is of greater importance than aerodynamics.
Specialized shift levers do exist that can be installed on some triathlon bars so that they can be reached without moving the hands from the aerodynamic position. The complementary brake levers in this handlebar configuration are placed in the ends of the accompanying pursuit bars.
Aero bars are a recent addition to road racing time trials, with Greg LeMond first using them in the 1989 Tour de France. In a controversial time trial on the final day, LeMond used them to beat yellow jersey wearer Laurent Fignon by 58 seconds, changing a 50-second deficit into an 8-second lead. Fignon protested at the use of these bars but was unsuccessful.