One area of particular interest in the evolution of American-made bicycles is the early "modern" lightweight or light roadster. When I say "early modern", I'm referring to the generation of bicycles with 26 x 1-3/8, 26 x 1.375, 26 x 1-1/4, or 26 x 1.25 tires, built from roughly 1938 to 1953.
This covers the generation of diamond frame (and traditional ladies step over frames) bicycles that makers like Schwinn and Westfield started building to rehabilitate the adult bicycle market in America.
Background
In the later part of the 19th century, there was a "bicycle boom" in which many adults began riding bicycles for exercise and transportation. In the early 1900s, this market crashed. By the 1930s, most of the American bicycle market was aimed at children and teenagers. In the early 1930s, the children's and teenagers' bicycle market was boosted by the arrival of bicycles using 26 inch "balloon tires" that involved a tire shell and inner tube.Reviving the American Bicycle for Adults
By the late 1930s, several American bicycle makers began thinking that they could also revive the adult bicycle market in the U.S. if they modernized their offerings for adults. Earlier adult bicycles had usually involved wooden rims and single tube tires, in which the inner tube and tire were a single unit. These bicycles were selling poorly by the 1930s. This led to the creation of such bicycles as the Schwinn Paramount, Schwinn Superior, Schwinn New World, Westfield/Columbia Sports Tourist, and Westfield/Columbia Sports Roadster. Other makers soon began to produce bicycles, such as Cleveland Welding Company and Manton & Smith.
While many of these bicycles look the same, they have some subtle differences. For consideration here are a 1947 Schwinn New World and a 1940 Westfield Sports Roadster.
The differences are subtle, but still apparent. The frame on the Westfield is more relaxed, while the Schwinn is a bit closer to an English type light roadster. The Schwinn has hand brakes, while the Westfield has a New Departure coaster.
Both of these bicycles represent a unique attempt by American manufacturers to revive adult cycling in America. These builders had visions of Americans taking to the road like the English or French, touring different places on vacation or commuting to work in cities.
Their attempts were not particularly successful, and a true, new "bike boom" in America would not take place until a generation later.