Bicycle frames are constructed from materials which place emphasis on being strong, lightweight and stiff to aid power transfer. Aluminum, titanium, steel and carbon are widely used in all levels of frame production.
Bootleg is a unique bicycle. You cannot buy it only with money; you must be also well aware of what you are buying. Bootleg is the top race bicycle. It is not everyman's bicycle; it cannot be mass-produced and sold in large quantities.
Bootleg is a ghost bicycle, just like certain airplanes, which are invisible to radars. It is a pirate bicycle, like certain ships, recordings or flags.
The black bicycle. The black sheep of the cycle market, a bête noire for competitors, something to be found on the black market at an unknown, yet steadily increasing price. Bootleg bikes are distributed on a limited scale.