Local bike shop bike shops have begun themselves to sell products online. A recent development is the introduction of brand specific stores from bicycle manufacturers such as Trek Bicycle Corporation. Other manufacturers, such as Specialized are strengthening their channels with "concept stores". According to the National Bicycle Dealers Association, in 2007 there were approximately 4,400 "specialty bicycle retailers" in the USA; down from 4,800 in 2005. Although they sold only 17% of the bikes, up from 16% in 2005, they collected 49% of the dollars, up from 47% in 2005. In 2004, the average specialty bicycle retailer had gross sales of $550,000 per
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