When the Japanese majors began to build large motorcycles, British bikes were the obvious model. Those bikes tended to have big wheels. The 1981 Honda CB900F, which seemed pretty sporty to those of us accustomed to Yamaha RD350s, had a 19-inch front wheel.
With its 11-inch brake discs plus the axle, a CB900F front wheel weighs 30 pounds, and the height from the top of the tire to the pavement is 27 inches. As a result of Superbike racing, wheels became smaller and lighter while brake discs got bigger.
All the manufacturers who participated in early Superbike races had problems with brakes and handling. Those new evolutionary forces benefited all riders because resistance of the front wheel to being steered is proportional to the square of the diameter of the wheel.
When the CB900F was converted into a Superbike, it was given a much smaller front wheel. A smaller front wheel is much easier to steer at high speeds than a taller wheel when the wheel is functioning as a powerful gyroscope.
The manufacturers quickly found out there was going to be a big difference between a motorcycle that could win Superbike races and a motorcycle that conformed to the visual standard of the late 1970s.
Kevin Cameron has been writing about motorcycles for nearly 50 years, first for Cycle magazine and, since 1992, for Cycle World. Kevin’s unparalleled experience and knowledge of the sport were—and continue to be—prompted by a lifetime of curiosity. His willingness to share that information with anyone who is willing to listen is likewise unique.
Kevin’s greatest strength lies in his ability to present complex subjects in simple terms with clarity and, often, humor. In this video series, shot in his home shop, Kevin draws upon his vast historical references to address modern-day questions. As Kevin has written, “Emotions bring us to engineering, but engineering then becomes a special way of confronting reality.”