The early to mid-nineties were a time of experimentation in the mountain bike world, a time when garage-based operations were trying to make their mark by manufacturing everything from anodized purple cranks to elastomer-sprung stems. Front suspension was beginning to catch on, and the first full suspension designs were emerging, but widespread acceptance was still a few years off. That left the door open for companies like Slingshot and their unique looking frame design, which used a steel cable and a spring for a downtube, to try and snag a piece of the mountain bike pie.
The design's origins date back to the early 1970s, when, according to the Museum of Mountain Bike Art and Technology, inventor Mark Groendal was riding a mini-motorcycle and noticed that it suddenly started feeling better when going over bumps. He examined the frame and discovered a crack in the downtube, sparking the idea that it might not be entirely necessary for that part of the frame to be completely solid.
The first iteration of the concept came in the form of a BMX bike that was released in the early 1980s, and in 1987 Groendal was awarded a patent for a 'flexible bicycle,' one where “the front frame portion can flex with respect to the rear frame portion by flexing the fiberglass spring plate and tensioning the cable against the bias of compression springs holding the cable in tensioned condition.”
As mountain biking's popularity grew, Groendal and his brother began making 26” wheeled versions using the same concept. The 1992 Team Edition shown here was the first year that the spring was attached to the head tube, rather than the bottom bracket as it had been in earlier versions. There were several different springs available, allowing riders to customize the amount of flex depending on their weight and personal preference.
Reviews of the bike were relatively positive, and while this was far from the cushy full-suspension bikes we take for granted today, there was enough flex that it did provide a more compliant ride than a traditional hardtail frame. Don't forget, this was still an era where fully rigid hardtails were still the norm - even a small amount of rudimentary shock absorption was a welcome change.The biggest hurdle that faced the company was based largely on aesthetics – the idea of a frame held together by a taut cable proved to be a stumbling block that many riders couldn't overcome. That, and the fact that some of the frame's compliance came in the form of lateral flex, giving the bike some 'interesting' handling when ridden aggressively.
The company changed owners in 1994, and faded from the spotlight as more refined full suspension bikes began to be released. However, unlike many of the smaller mountain bike companies that popped up in the 1990s, Slingshot Bikes didn't disappear completely, and even after all these years they still produce bikes that rely on that same distinctive downtube design.
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Special thanks to The Pro's Closet for once again allowing us access to their treasure trove of historic bikes. Bike photos courtesy of The Pro's Closet