Motorcycle brakes are generally comprised of a system wherein the front and rear brakes are operated independently by the hand and foot respectively, and in order to stabilize the behaviour of the vehicle and bring out maximum brake performance it is necessary to skilfully balance the hand and foot input. Accordingly, in this paper we present a CBS (Combined Brake System) in which the hand and foot operated systems together apply braking to the front and rear wheels simultaneously. Braking tests were performed by varying the front and rear braking force distribution characteristics, and tests were performed to find a braking force distribution characteristic which also allows easier handling for riders who are accustomed to a conventional brake system. As a result, it was learned that brakes which can be easily operated by a rider accustomed to a conventional brake system can be obtained by means of a hand operated system CBS in which locking of the front wheel occurs before the rear wheel, and a foot operated system CBS in which, conversely, locking of the rear wheel occurs before locking of the front wheel. Using a test vehicle fitted with a CBS adjusted for a braking force distribution characteristic of this kind, measurements were taken of the dispersion of the deceleration produced by riders of varying levels of skill. Further, vehicle behaviour was measured during braking with the same characteristic, and comparisons were made with vehicle behaviour when a conventional brake system was used. As a result, when comparison was made of independent hand and foot operation, the generated deceleration was higher and the dispersion due to differences in the rider's skill was smaller with the use of the present CBS than with a conventional brake system. Further, it was learned that changes in the vehicle's behaviour were also smaller with the CBS.
Abstract