A fixed-gear bicycle is a bicycle that has a drivetrain with no freewheel mechanism
such that the pedals always will spin together with the rear wheel. The freewheel was developed early in the history of bicycle design but the fixed-gear bicycle remained the standard track racing design. More recently the "fixie" has become a popular alternative among mainly urban cyclists, offering the advantage of simplicity compared with the standard multi-geared bicycle.
A fixed-gear bicycle
An 18-tooth sprocket that attaches to the rear hub of fixed-gear bike
Track sprockets are typically attached and removed from the hub by screwing them with a chain whip. This tool incorporates a lockring spanner for securing a reverse threaded lockring against the sprocket.
Cyclist riding a fixed gear bicycle without brakes
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 bicycle of a similar style but built more for endurance and less the fast bursts of speed desired in a racing bicycle; as such, they usually have more gear combinations and fewer hi-tech racing features. Certain of these bicycles have been referred to as 'sportive' bicycles to distinguish them from racing bicycles.
An aluminum road bicycle made by Raleigh and built using Shimano components. It uses wheels with a low spoke count for reduced air drag.
The steel frame racing bicycle by the Italian company Bianchi used by Fausto Coppi to win the 1949 Milan–San Remo race