A carbon fiber frame racing bicycle by the French company LOOKA road bicycle made by ScottLance Armstrong riding in a posture often used on a road bicycle
Racing bicycles are designed for maximum performance while remaining legal under the UCI rules. They are designed to minimise aerodynamic drag, rolling resistance, and weight, and balance the desire for stiffness for pedaling effiency with the need for some flexibility for comfort. Racing bicycles sacrifice comfort for speed compared to non-racing bicycles. The drop handlebars are positioned lower than the saddle to put the rider in a more aerodynamic posture. The front and back wheels are close together so the bicycle has quick handling, which is preferred by experienced racing cyclists. The derailleur gear ratios are closely spaced so that the rider can pedal at their optimum cadence. However, racing bicycles must retain the ability to maneuver safely within a tightly-packed peloton, and be sufficiently comfortable to ride for races of six hours or more.
Bicycles and most wheels ridden in professional competition must be type-approved by the UCI,[1] and made available for commercial sale.[2] It is common for professional road cycling teams to use prototype bicycles and equipment before they become commercially available.
Racing bicycles are generally legal for use on public roads and are widely used for non-racing fitness and utility riding.
Time trial bicycles are a subset of road bicycles that are designed for time trial events. The UCI rules for these bikes are slightly less prescriptive than those for "massed start road races" (see rules 1.3.020 to 1.3.023).
Owing to the lower air resistance and better body stance for pushing, road bicycles tend to be more efficient for use on smooth roads. Cyclo-cross bicycles, which are used for racing on off-road circuits, are closer to racing bikes than to mountain bikes. They have wider, treaded tires are less efficient than racing bikes at higher speeds on sealed roads. Gravel bicycles evolved from cyclo-cross bicycles and are drop-bar bicycles designed for riding on maintained but unsealed roads, often over very long distances.
Frame
The frame of a road bicycle must, according to the UCI regulations, be constructed using a "main triangle" with three straight tubular shapes—the top tube, down tube, and seat tube. These three tubes, and other parts of the frame, need not be cylindrical, however, and many racing bicycles feature frames that use alternative shapes. Traditionally, the top tube of a racing bicycle is close to parallel with the ground when the bicycle is in its normal upright position. Some racing bicycles, however, have a top tube that slopes down towards the rear of the bicycle; the "compact" frame geometry was popularized by Giant.[citation needed]
Frame manufacturers are free to use any material they choose in the frame. For most of the history of road racing, bicycle frames were constructed from steel tubing, and aluminium and titanium alloys were also used successfully in racing bicycles. Racing bicycles in these three materials are still commercially available and are still used by some amateur racing cyclists or in vintage racing classes. However, virtually all professional road racing cyclists now use frames constructed from various carbon fiber composite materials,[citation needed] and a typical modern carbon fiber frame weighs less than 1kg (2.2lbs).
Particularly since the introduction of carbon fiber frames, the shape of the tubes that make up the frame has increasingly diverged from the traditional cylinder, either to modify the ride characteristics of the bicycle, reduce weight, or simply achieve styling differentiation. However, a recent trend in road bicycle frame design is tubing claimed to reduce aerodynamic drag, adopting many design features from time trial bicycles, and the majority of top-level teams use bikes with aerodynamic tube shaping at least some of the time.
Unlike mountain bikes, most road bicycles do not have a dedicated suspension. The majority of damping is provided by the tires, padding in a cyclist's clothing, seat, and handlebar tape. Wheels, frames, and forks provide a limited amount of flex, and manufacturers tune the thickness and construction of frame tubing to offer the best compromise between a stiff frame (desired for pedalling efficiency, particularly when sprinting) and ride comfort. Additionally, a few manufacturers offer racing bicycles using additional flexing points or vibration-absorbing materials at key points in the frame for additional comfort.[7]
Wheels and tires
Most road bicycles use 700C bicycle wheels (622mm bead seat diameter), with matching tyres that are 23-28 mm wide. Wider tires became more common over the 2010s, as more sophisticated measurement showed that wider tires increase rider comfort, improve grip, and decrease rolling resistance without unduly affecting aerodynamics.
The wheels greatly affect the performance of a racing bike. The rim of the wheel can be shaped for greater aerodynamic efficiency making a triangular cross-section to form a teardrop with the tire.
For aerodynamics and rotating weight, it is generally better to reduce the number of spokes in the wheel. For high-end wheelsets, the spokes can be shaped to have a bladed cross-section, further reducing wind resistance.
The most common wheel material for professional racing is now molded carbon fiber rims being a popular choice for pro-level racers and enthusiasts. Aluminium rims are still widely used outside racing and by some less well-funded amateur racers. Carbon fiber rims are lighter than the same shape in aluminium, allowing riders to choose "deeper", more aerodynamic rims without an unacceptable weight penalty. Race-grade wheelsets are very expensive and often fragile. Riders who race often choose to own at least two pairs of wheels: a heavier, more durable, and cheaper wheelset for training, and a lighter, more aerodynamic wheelset for racing. Racers with sufficient resources may have multiple racing wheelsets to choose from depending on the course and weather conditions; deeper rims lose their aerodynamic advantage, and are hard to control, in high crosswinds, and on mountainous courses the lightest possible wheelset may be preferred by some riders.
To reduce both air resistance and rolling resistance on the road, tires are lightweight, narrow, and have a thin, smooth tread. Track racing tires can be inflated up to circa 200 pounds per square inch (14bar). Tires for road racing used to be inflated to pressures almost as high in the belief that this minimised rolling restistance. However, it was discovered that on real road surfaces, much lower tyre pressures or around 70 pounds per square inch (4.8bar), depending on rider weight and conditions, result in both a more comfortable ride and lower rolling resistance.[8] Until recently, most racing bikes used tubular tires which have no beads: they are sewn around the tube and glued to the rim. These tires provide an advantage in weight (lacking the relatively heavy wire bead), grip and pinch flat protection, but their greatest advantage lies in the ability to use a very lightweight simple box-section rim, rather than the U-shaped clincher rim. A U-shaped clincher rim must be made of relatively heavier gauge material to prevent the tire pressure from spreading the inherently weak U shape and allowing the tire to come off the rim. Advances in tire technology, however, have seen the far more practical (due to greater ease of changeability) clincher (beaded) tire close the gap.[9] Some teams are using tubeless tires, which are claimed to offer the resistance to pinch flats of tubular tires, as well as greater ease of fitment and lower rolling resistance than tubulars.[10]
Wheel moment of inertia is a controversial subject. In this article: wheel theory, the author does some calculations on wheel effects. Moment of inertia changes result in a decrease in watts of between .004 and .022%, while lower mass provided between .2 and .46%, and better aerodynamics provided between .6 and 1.8% decrease in power. Based on this it can be argued that wheel moment of inertia effects are neither noticeable nor important. At the same time, a product launched in 2008 to dynamically alter the rotating inertia of bicycle wheels claims to have "outperformed the standard, equivalent wheel by 5.6 seconds per mile" (or about 3.5 seconds per km).[11]
Road bike components are collectively referred to as the groupset. The quality of the groupset determines how refined the bike feels, how much maintenance it requires, and contributes to the performance of the bike. The three major groupset manufacturers of complete groupsets for racing bicycles are Shimano, SRAM, and Campagnolo. Some companies only produce specific components of the groupset, such as Full Speed Ahead (often abbreviated to FSA). The companies have different design strategies, and some cyclists have great brand loyalty for one or the other.
In the early 1990s, Shimano introduced dual-control with a system called Shimano Total Integration (STI). STI is characterized by its combined brake and shift levers, or "brifters". Previously,[when?] the shifters were mounted on the stem, handlebar ends or the down tube of the frame. Dual control addressed the problem of having to reposition a hand to change gears. STI was followed by the competing Campagnolo/Sachs Ergolever. SRAM uses a technology known as Double Tap for their integrated shifter/brake lever.
In the mid 1990s Mavic, known for their wheelsets, introduced an electronic shifting system which was pioneered in the Tour de France by American Greg LeMond and later on by Briton Chris Boardman, who liked the fact that the system allowed him to shift from his aerobars and his brake levers. The system did not catch on due to technological hurdles. In 2009, Shimano commercially released the Dura-Ace Di2 electronic shifter, and Campagnolo and SRAM followed suit in the early 2010s. As of 2022, the vast majority of top-level professional teams use electronic shifting, as do many amateur riders. Mechanical derailleurs remain popular with amateur racers and recreational riders for cost reasons.
Groupset manufacturers have gradually increased the number of gears on racing bicycles, allowing a greater range between the highest and lowest gears while maintaining relatively small gaps between each successive gear. As of 2022, most racing bicycles used in professional racing have 2 front chainrings and 11 or 12 gears on the rear cassette.
Carbon fiber has also become more popular for components. Shimano, Campagnolo and SRAM have introduced carbon fiber for their high-end shifters and brake levers, cranks, and parts of their derailleurs. Carbon fiber stems, handlebars, shoe soles, forks and seatposts are also more commonplace, including integrated stem/handlebar combinations. The advantages of carbon fiber are low weight as well as increased vibration damping leading to a more comfortable ride.
As of 2022, the majority of professional teams use hydraulic disc brakes for most or all races. A few top-level professional teams still use bikes with caliper brakes in mountain stages, as their disc-brake models are significantly heavier than the UCI's legal minimum weight of 6.8kg. Disc brakes offer better stopping performance, particularly in wet conditions. For many years, racing bicycles were required to use caliper brakes by UCI regulation, but manufacturers began producing road bikes with disc brakes for recreational use in the mid-2010s, and their use was trialled in professional racing in 2016 and 2017. Rider disquiet over the crash safety of disc brakes led to the introduction of versions with chamfered edges to reduce the risk of the rotating disc acting as a cutting blade. In 2018, the UCI concluded the trial and legalised the use of disc brakes in all road racing events.
Non-competitive uses
Road bicycles are built for casual recreational use, often labeled as "sportif" bicycles or "dropped-bar fitness bikes". These have much in common with a competitive racing bicycle, but the frame geometry is relaxed to make the bicycle more comfortable over long distances, though less effective for short bursts of speed. They usually have a wider range of gear ratios (with greater gaps between each ratio) and fewer high-tech racing features.[12]
For recreational road cycling, the road-style bicycles with drop handlebars used to be the norm in the 1980s, along with the touring bicycle (a drop-handlebar bike with a slightly longer wheelbase to provide a smoother ride and less sensitivity to steer and balance disturbances). These designs, called "road bikes" or colloquially, "roadies" or "racing bikes", have become less popular in recent years[when?]. The Mountain bike geometry, with its straight handlebars and upright sitting position (resembling the city bike), have moved into the high-performance spaces, and high production volumes have brought down costs significantly.
UCI rules
The UCI rules currently specify[13] that a road bicycle have the following characteristics:
be a vehicle with a front wheel steered by a handlebar and a rear wheel driven by a system comprising pedals and a chain by the legs moving in a circular movement
that the only points of support are the following: the feet on the pedals, the hands on the handlebars and the seat on the saddle
wheels must be of equal diameter, between 70cm and 55cm, and must have minimum 12 spokes; spokes can be round, flattened or oval, as far as no dimension of their sections exceeds 10mm
maximum length 185cm
maximum width 50cm
the peak of the saddle must be at least 5cm behind a vertical plane passing through the bottom bracket spindle
the saddle must be between 24cm and 30cm in length
the distance between the bottom bracket spindle and the ground must be between 24cm and 30cm
the distance between the vertical passing through the lower bracket spindle and the front wheel spindle must be between 54cm and 65cm
the distance between the vertical passing through the bottom bracket spindle and the rear wheel spindle must be between 35cm and 50cm
the maximum internal distance between the front fork ends is 10.5cm, and of the rear stays 13.5cm
frame must be built around a main triangle, constructed of tubular elements (that may have non-circular cross-sections) such that the form of each encloses a straight line
The maximum height of the frame elements shall be 8cm and the minimum thickness 2.5cm. The minimum thickness shall be reduced to 1cm for the chain stays and the seat stays. The minimum thickness of the elements of the front fork shall be 1cm; these may be straight or curved. The top tube may slope, provided that this element fits within a horizontal template defined by a maximum height of 16cm and a minimum thickness of 2.5cm
Note that the regulations regarding the dimensions of the bike are allowed exception, given that the rider can demonstrate a morphological need for the exception based on limb size or other factors.
These rules effectively and purposely rule out recumbent bicycles, and have done so since 1934.
A bicycle, also called a pedal cycle, bike, push-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 bicycle rider is called a cyclist, or bicyclist.
A tandem bicycle or twin is a form of bicycle designed to be ridden by more than one person. The term tandem refers to the seating arrangement, not the number of riders. Patents related to tandem bicycles date from the mid 1880s. Tandems can reach higher speeds than the same riders on single bicycles, and tandem bicycle racing exists. As with bicycles for single riders, there are many variations that have been developed over the years.
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 makes them heavier, more complex and less efficient on smooth surfaces. These typically include a suspension fork, large knobby tires, more durable wheels, more powerful brakes, straight, extra wide handlebars to improve balance and comfort over rough terrain, and wide-ratio gearing optimised for topography and application. Rear suspension is ubiquitous in heavier-duty bikes and now common even in lighter bikes. Dropper posts can be installed to allow the rider to quickly adjust the seat height.
A recumbent bicycle is a bicycle that places the rider in a laid-back reclining position. Some recumbent riders may choose this type of design for ergonomic reasons: the rider's weight is distributed comfortably over a larger area, supported by back and buttocks. On a traditional upright bicycle, the body weight rests entirely on a small portion of the sitting bones, the feet, and the hands.
A tricycle, sometimes abbreviated to trike, is a human-powered three-wheeled vehicle.
A bicycle frame is the main component of a bicycle, onto which wheels and other components are fitted. The modern and most common frame design for an upright bicycle is based on the safety bicycle, and consists of two triangles: a main triangle and a paired rear triangle. This is known as the diamond frame. Frames are required to be strong, stiff and light, which they do by combining different materials and shapes.
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels.
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 flagship components are the Super Record, Record, and Chorus groupsets with all three representing their recent shift to 12-speed drivetrains. Super Record and Record are the top groupsets, followed by Chorus, Potenza, Centaur and Veloce. Campagnolo also produces aluminum and carbon wheels, as well as other components.
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, frame materials that favor flexibility over rigidity, heavy duty wheels, and multiple mounting points.
A utility bicycle,city bicycle, urban bicycle, European city bike (ECB), Dutch bike, classic bike or simply city-bike, is a bicycle designed for frequent very short, very slow rides through very flat urban areas. It is a form of utility bicycle commonly seen around the world, built to facilitate everyday short-distance riding in normal clothes in cold-to-mild weather conditions. It is therefore a bicycle designed for very short-range practical transportation, as opposed to those primarily for recreation and competition, such as touring bicycles, racing bicycles, and mountain bicycles. Utility bicycles are the most common form globally, and comprise the vast majority found in the developing world. City bikes may be individually owned or operated as part of a public bike sharing scheme.
A cyclo-cross bike or 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.
A track bicycle or track bike is a bicycle optimized for racing at a velodrome or outdoor track. Unlike road bicycles, the track bike is a fixed-gear bicycle; thus, it has only a single gear ratio and has neither a freewheel nor brakes. Tires are narrow and inflated to high pressure to reduce rolling resistance.
The Birdy is a folding bicycle designed by Riese und Müller in Germany and produced by Pacific Cycles in Taiwan. As of 2010 over 100,000 had been sold. Three distinct models have been marketed, in addition to some specialist variations, with the third (Mk3) introduced in July 2015.
Zipp is an American company that is best known for designing, manufacturing, and marketing carbon-composite bicycle wheels for road cycling, triathlons, track racing, and mountain biking. The company's product range also includes handlebars, stems, seat posts, tires, inner tubes, handlebar tape, and bags.
Bicycle and motorcycle dynamics is the science of the motion of bicycles and motorcycles and their components, due to the forces acting on them. Dynamics falls under a branch of physics known as classical mechanics. Bike motions of interest include balancing, steering, braking, accelerating, suspension activation, and vibration. The study of these motions began in the late 19th century and continues today.
Time trials have been part of cycling for more than a hundred years. The first time trial was run in 1895 after a ban on road racing was imposed by the National Cyclists' Union. It wasn't until 1939 that the time trial made its world stage debut as an official stage of the Tour de France. It was originally used as a method of drawing more people to listen to the Grand Tour on the newly available radio broadcast of the 1939 race. The main thing that distinguished the first time-trial from the traditional form of road racing was that the riders started at intervals instead of one large group and they raced against the clock instead of each other. Unlike road racing where the a rider can hang in the peloton and draft off of other riders to conserve energy, time trial races put the rider out alone on the course. There are no breaks and no one to draft off, causing a rider to push as hard as they can the entire race. Bicycles have also evolved to accommodate this new form of racing, with most of the breakthroughs occurring in the last 40–50 years with the introduction of triathlons.
Mountain bike trials, also known as observed trials, is a discipline of mountain biking in which the rider attempts to pass through an obstacle course without setting foot to ground. Derived from motorcycle trials, it originated in Catalonia, Spain as trialsín and is said to have been invented by Pere Pi, the father of Ot Pi, a world champion motorcycle trials rider. Pi's father had wanted his son to learn motorcycle trials by practicing on an ordinary bicycle.
A gravel bicycle is a type of bicycle intended for gravel cycling, including gravel racing. They are also sometimes known as "adventure bicycles", particularly ones intended for harsher off-road terrain.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
