Racing bicycle
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.
The front and back wheels are close together so the bicycle has quick handling, which is preferred by experienced racing cyclists.
Bicycles and most wheels ridden in professional competition must be type-approved by the UCI,[1] and made available for commercial sale.
Racing bicycles are generally legal for use on public roads and are widely used for non-racing fitness and utility riding.
They have wider, treaded tires and are less efficient than racing bikes at higher speeds on sealed roads.
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.
The majority of damping is provided by the tires, padding in a cyclist's clothing, seat, and handlebar tape.
The rim of the wheel can be shaped for greater aerodynamic efficiency making a triangular cross-section to form a teardrop with the tire.
The most common wheel material for professional racing is now molded carbon fiber rims being a popular choice for pro-level racers and enthusiasts.
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.
Tires for road racing used to be inflated to pressures almost as high in the belief that this minimised rolling restistance.
[8] Until recently, most racing bikes used tubular tires which have no beads: they are sewn around the tube and glued to the rim.
Some companies only produce specific components of the groupset, such as Full Speed Ahead (often abbreviated to FSA).
In 2009, Shimano commercially released the Dura-Ace Di2 electronic shifter, and Campagnolo and SRAM followed suit in the early 2010s.
Mechanical derailleurs remain popular with amateur racers and recreational riders for cost reasons.
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.
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 6.8 kg.
