A unitary fiber reinforced plastic aerodynamic bicycle handlebar is molded with a one piece base bar having tubes that slidably receive forward handlebar extensions, the extensions being either locked in place with binder collars, or telescopingly mounted, and either the extensions receiving arm pad brackets or the arm pad brackets being mounted to the base bar, the base bar extending outwardly and terminating in grips, the extensions permitting the rider to assume an aerodynamic position and the grips enabling control while maneuvering, an improved stem permitting a light weight, aerodynamic mounting of the bar to a bicycle.