Unlike its progenitors, the Klunker proved incapable of withstanding hard off-road use, and after an unsuccessful attempt to reintroduce the model as the Spitfire 5, it was dropped from production. Another problem was Schwinn’s failure to design and market its bicycles to specific, identifiable buyers, especially the growing number of cyclists interested in road racing or touring. Instead, most Schwinn derailleur bikes were marketed to the general leisure market, equipped with heavy “old timer” accessories such as kickstands that cycling aficionados had long since abandoned. More and more cyclists, especially younger buyers, began to insist on stronger steel alloys (which allowed for lighter frames), responsive frame geometry, aluminum components, advanced derailleur shifting, and multiple gears.[8][30] When they failed to find what they wanted at Schwinn, they went elsewhere.
In reality, mass-market French manufacturers such as Peugeot were not infrequently criticized for material and assembly quality — as well as stagnant technology — in their low- and mid-level product lines. Nevertheless, Peugeot proudly advertised its victorious racing heritage at every opportunity. By 1979, even the Paramount had been passed, technologically speaking, by a new generation of American as well as foreign custom bicycle manufacturers. By the late 1970s, a new bicycle sport begun by enthusiasts in Northern California had grown into a new type of all-terrain bicycle, the mountain bike.
Mountain bikes were originally based on Schwinn balloon-tired cruiser bicycles fitted with derailleur gears and called “Klunkers”. A few participants began designing and building small numbers of mountain bikes with frames made out of modern butted chrome-molybdenum alloy steel. When the sport’s original inventors demonstrated their new frame design, Schwinn marketing personnel initially discounted the growing schwinn mountain bike popularity of the mountain bike, concluding that it would become a short-lived fad.[39] The company briefly (1978–1979) produced a bicycle styled after the California mountain bikes, the Klunker 5. Using the standard electro-forged cantilever frame, and fitted with five-speed derailleur gears and knobby tires, the Klunker 5 was never heavily marketed, and was not even listed in the Schwinn product catalog.
While the Paramount still sold in limited numbers to this market, the model’s customer base began to age, changing from primarily bike racers to older, wealthier riders looking for the ultimate bicycle. Schwinn sold an impressive 1.5 million bicycles in 1974, but would pay the price for failing to keep up with new developments in bicycle technology and buying trends. While every large bicycle manufacturer sponsored or participated in bicycle racing competition of some sort to keep up with the newest trends in technology, Schwinn had restricted its racing activities to events inside the United States, where schwinn bicycles predominated. As a result, Schwinns became increasingly dated in both styling and technology. By 1957, the Paramount series, once a premier racing bicycle, had atrophied from a lack of attention and modernization. Aside from some new frame lug designs, the designs, methods and tooling were the same as had been used in the 1930s.
W. Schwinn, grandson Frank Valentine Schwinn took over management of the company. Schwinn was soon sponsoring a bicycle racing team headed by Emil Wastyn, who designed the team bikes, and the company competed in six-day racing across the United States with riders such as Jerry Rodman and Russell Allen. Developed from experiences gained in racing, Schwinn established Paramount as their answer to high-end, professional competition bicycles. The Paramount schwinn bicycles used high-strength chrome-molybdenum steel alloy tubing and expensive brass lug-brazed construction. During the next twenty years, most of the Paramount bikes would be built in limited numbers at a small frame shop headed by Wastyn, in spite of Schwinn’s continued efforts to bring all frame production into the factory. At the close of the 1920s, the stock market crash decimated the American motorcycle industry, taking Excelsior-Henderson with it.