The Birth of the Modern Machine
The wheels, frame, handlebars are all made of forged steel. The pedals are “direct drive” meaning that when the pedals turn, the bike moves; if the pedals don’t turn, the bike does not move. No brakes. Nick-named “bone crushers” because of the tendency of riders to fall off.
Contrast the pennyfarthing bicycle. The wheels are still made of forged steel, as is the frame. An innovation is the large front drive wheel. Note the position of the pedals. For every turn of the pedals, the large front wheel turns a large distance. These bicycles go faster than “bone crushers” because of the mechanical advantage of the big front wheel. They are still very heavy, since they are made of solid steel, and very bumpy to ride.
Here is a catalog illustration of a British Sunbeam bicycle, available in 1899. You can see that in basic outline it looks like many bicycles available today: two same-sized wheels, a diamond-shaped frame made of steel tubing, air-filled rubber tires, a metal chain drive.
This bicycle has a derailleur and multiple gears, an invention from the 1890s. It has brighter colors, lighter materials, a more comfortable seat. The chain, freewheel, pulled tubes, and inflated tires designs are much the same as those from 1900.
Here is a Chinese Flying Pigeon bicycle, one of the most popular bicycles in the world, used widely in Asia and Africa.