what is a racing bicycle

Racing bicycle

     A racing bicycle, also known as a road bike is a designed for competitive road cycling, a sport governed by according to the rules of the union cyclist internationale. The UCL rules were altered in 1934 to exclude recumben bicyle.

     The most important characteristics about a racing bicycle are its weight and stiffness which determine the efficiency at which the power from a rider's pedal strokes can be transferred to the drive-train and subsequently to its wheels.  To this effect racing bicycles may sacrifice comfort for sped.  The drop handlebars are positioned lower than the saddle in order to put the rider in a more aerodynamic posture.  The front and back wheels are close together so the bicycle has quick handling.  The deraileur gear ratios are closely spaced so that the rider can pedal at their optimum cadence.  Other racing bicycles, especially those used in time trialling, prioritize aerodynamics over comfort.

 Distinction between racing bicycles and others

     Bicycles for racing on velodromes are track bicycles. bicycles for racing off road are mountain bicycles, cyclo-cross bicycles or cycle speedway bicycles, bicycles that race according to the rules of the international human powered vehicle association include faired recumben cycles which, on flat ground, are the fastest bicycles in the world.  Recumbents were excluded from the uci definition of a bicycles on 1 april 1934.

      Time trial bicycles are a subset of racing bicycles that are desingmend for time trial events.  The uci rules for these bikes are slightly less prescriptive than those for massed start road races.

     Tiathlon bicycles are governed by international tiathlon union rules, which allow more recent technological developments than do the uci rules.

frame

     The frame of a racing 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, that use alternative shapes.  Traditionally, the top tube ofer 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.

     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 successfullyu 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 materialsm and a typical modern carbon fiber frame wighs less than 1 kg.

     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 differetiation.  However a recent trend in road racing bicycle frame desing is tubing claimed to reduce aerodynamic drage, adopting many desing features from time trial bicycles.  While many professional riders use such bicycles, as of 2012 they have not been universally adopted in the professional peloton.  Such frames are typically slightly heavier than comparably priced frames without aerodynamic shaping and reviews of such bicycles have indicated that ride and handling characteristifs of many have been inferior to more conventional bicycles.

Racing wheels and tires

    Most road racing bicycles use 700c bicycle wheels with matching 20-25mm wide tires.  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 hill climbs, however enery losses due to the higher wamic rims are greater than the aerodynamic drag reductio eight of most aerodynamic offer so a traditional lighter box sectioned rim is oftern used to make it go easier.