Achieving nearly 30% weight reduction using aluminum frame. Carbon fiber is also drawing the attention in the field of bicycle applications.
Bicycling constitutes a fast growing application field among other sports applications. Full-scale bicycle road races are major events in Europe, but in Japan, too, we are seeing more road bikes dashing on special paths and mountain bikes conquering mountain courses and other offroad terrains in the past several years, where bicycles using carbon fiber are featured as "carbon bikes" in domestic cycle magazines. A bicycle consists of "framework structures" such as the frame and fork handle bars, and "components" transmitting/controlling drive force such a the wheels, cranks, gears, transmission break and brake lever. TORAYCA® textile and prepreg products found its way into front forks developed by a Taiwanese bicycle manufacturer in the mid 1980s, and wheel disks, advanced carbon monocock frames, etc., began emerging. Thereafter, application of carbon fiber in monocock bodies itself stalled due to the need for large-scale facility to accommodate frame-size mold and issues relating to control technology, etc., but frames connecting carbon pipes (eight pipes, or also called tubes, constituting the front triangle and rear triangle) with lugs (joints) were subsequently developed by utilizing the pipe forming technology such as golf shaft, rod, and racket involving unidirectional prepreg and textile prepreg that were developed for golf shafts, fishing rods, rackets, etc., and use of carbon fiber to mountain bikes and road bikes progressed in Taiwan, Italy, etc. Application of carbon fiber to wheel rims, cranks and other components also accelerated through use of prepreg, contributing to improvement of the frame requiring weight reduction and rigidity improvement. Currently a complete production bike using carbon frame can weigh 7 kg or less, compared to one using aluminum frame weighing 9.5 kg, which is a weight reduction of nearly 30%. As the progress and actual application of frame production technology and progress of design/evaluation technology drive weight reduction and improve mass producibility, further application efforts are made to utilize the characteristic light weight/high rigidity of carbon fiber TORAYCA®.