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@DotDash
what is needed, rather is an added negative feedback stage to limit braking force in dry conditions to less than the amount that would result in the rider'd being brojected over the handlebars. A braking system incorporating such a combination of positive and negative feedback (fig. 7.1) was developed by calderazzo (hopgood 1979). Only the rear-wheel brake is
activated by the rider. The rear brake is mounted on a lever pivoted near the wheel axis so that it is carried forward during braking. In moving forward, it actuates (through a cable or hydraulic line) the front brake, with any reasonable desired degree of force multiplication. Accordingly, little effort need be required for strong braking to be obtained. At the point at which the rear wheel would start skidding, braking at the front is automatically limited. In hundreds of tests with this system in which testers made "panic stops" from high speeds on different surfaces, never did a rider begin to go over the handlebars. (the front forks of the test bicycle eventually failed through fatigue: testimony to braking effectiveness and to the inadequacy of the design of the fork). This promising system apparently died in Patent litigation. As mentioned earlier, it could well be used to actuate other types of brake (e.g a coaster brake) in the front wheel.