Cruiser bicycle Sears, Roebuck and Company, the Elgin Motor Bike was advertised, and the term motor-bike was explained as follows, "The term "Moto-Bike" has reference only to the type of frame, meaning that it is built on the order of a motorcycle". Schwinn was one of many manufacturers who contributed to the development of the cruiser at a time when U.S. bicycle sales had declined sharply due to the Great Depression; adults purchased few bicycles, which were seen as luxury products intended largely for sport or recreation. In response to other manufacturers' innovations, Schwinn conceived their own sturdy, affordable bicycle designed for
Racing bicycle using a "main triangle" with three straight tubular shapes—the top tube, down tube, and seat tube. These three tubes, and other parts of the frame, need not be cylindrical, however, and many racing bicycles feature frames that use alternative shapes. Traditionally, the top tube of a racing bicycle is close to parallel with the ground when the bicycle is in its normal upright position. Some racing bicycles, however, have a top tube that slopes down towards the rear of the bicycle; the "compact" frame geometry was popularized by Giant. Frame manufacturers are free to use any material they choose in