In 1973, Gary Klein was a graduate student at the Massachusetts Institute of Technology (MIT). As an engineer and as a competitive road racer, Klein was interested in developing a bicycle frame that was stronger and more responsive than those currently available. Klein developed a prototypical oversized tube design aluminum frame as a part of an MIT independent study course, a design he took to limited production in 1975.
The Klein frame was revolutionary; Klein may not have been the first person to theorize as to how aluminum could be employed as a material in frame construction, but he was the first to advance the concept of the oversized aluminum frame. Steel had been the material of choice for most cycle manufacturers as it is a stiff material, approximately three times as stiff as aluminum. Conventional wisdom in the early 1970s world of cycling manufacturing was that an aluminum bicycle, while lightweight, would lack the stiffness to perform. Aluminum bicycles were derided as spaghetti bikes, frames that lacked the stability required by a serious athlete. Klein theorized that if the tubes used to construct the frame were of a larger circumference, an aluminum frame would possess an even greater stiffness at a lighter weight than the conventional steel frames. Klein's aluminum frames were approximately 15% lighter than the conventional models. Klein determined that a 1.5 in circumference aluminum tube (3.75 cm) was approximately five times stiffer than a 1-in (2.5 cm).
Klein developed a proprietary welding process to compliment his frame designs, creating smooth, aerodynamic welds at each join in the frame. Klein ultimately patented 18 different designs and processes in relation to his aluminum frames.
The modern Klein designs have maintained a cutting edge status among both mountain biking and road cyclists. The frames manufactured today are a variety of aluminum and carbon fiber composite constructions.
Klein parlayed his frame development into the multi-faceted Klein Bike company, producing mountain bikes and road bicycles for the international market. As modern bicycle development moves further in direction of frames made from carbon fiber composites, it is likely that the Klein oversized aluminum frame will be given its proper recognition as an important historical step in the development of faster, lighter, and more responsive bicycles.
SEE ALSO Cycling.