Drawing by Keithonearth
The classic “men’s” bicycle frame design is often called a “diamond frame.” This basic configuration hasn’t changed since 1885 when the first “safeties” appeared.
The illustration above shows the names of the specific components.
Not labeled are the attachment points for the wheels, called the dropouts. Sometimes the front dropouts are called fork ends.
The two sides of the fork between the frent wheel are “fork blades,” and the fork tube inside the head tube is the “steering tube.”
The large diameter short tube that houses the bottom bracket (crank) bearings is the “bottom bracket” or more specifically “bottom bracket shell.”
Sometimes people will call the area where the top of the seat stays join the seat tube the “seat cluster.”
Diamond frames are most often made from steel alloys. An alloy of steel means trace amounts of other materials are mixed in to give the steel desired characteriscs. A good bike frame should be durable, lightweight, yet just a touch springy.
Aluminum alloy frames are also common. They weigh considerably less, but are a bit less springy, wasting a fraction of the rider’s energy by turning flex into heat, rather than springing back with nearly full energy.
Bike frames have been made from other materials, such as carbon fiber, also known as “graphite,” fiberglas, wood, and even plastic. No one has tried making a frame from ketchup, yet.