Abstract: In a brake control method for a motorcycle which includes a front master cylinder, front wheel cylinders hydraulically connected to the front master cylinder, a rear master cylinder, a rear wheel cylinder hydraulically connected to the rear master cylinder and a hydraulic pressure pump. When only the front master cylinder is operated, brake pressure fluid is supplied to the front wheel cylinders and the fluid pressure pump is driven to supply discharging pressure fluid to the rear wheel cylinder, and when only the rear master cylinder is operated, brake pressure fluid is supplied only to the rear wheel cylinder.

Abstract: When a method for operating a reference speed judges that an ABS control is being executed, the method judges whether the ABS control is being executed to a front wheel or not. When the method judges that the ABS control is not executed to the front wheel, the method considers that the lifting of a rear wheel does not occur, and makes the reference speed follow the fastest wheel speed VRH. When the method judges that the ABS control is being executed to the front wheel, and further judges that a reference body deceleration is a predetermined value or more, the method considers that the lifting of the rear wheel has occurred, and makes the reference speed follow a speed VRM. The speed VRM is a wheel speed calculated in accordance with the following formula: VRM=&agr;VRL+(1−&agr;)VRH (0<&agr;<1), where &agr; character VRL indicates the slowest wheel speed, and a character &agr; indicates a default.

Abstract: To provide a technique capable of detecting lifting of a rear wheel of a two-wheeled vehicle correctly and rapidly. An estimated vehicle speed is generated by selecting the larger one of wheel speed Vf, Vr of a rear wheel and a front wheel, and attention is paid to an estimated vehicle deceleration which is computed based on the estimated vehicle speed and it is judged that lifting of the rear wheel has occurred when a degree of lowering of the estimated vehicle deceleration is a predetermined value or larger.

Abstract: When a method for operating a reference speed judges that an ABS control is being executed, the method judges whether the ABS control is being executed to a front wheel or not. When the method judges that the ABS control is not executed to the front wheel, the method considers that the lifting of a rear wheel does not occur, and makes the reference speed follow the fastest wheel speed VRH. When the method judges that the ABS control is being executed to the front wheel, and further judges that a reference body deceleration is a predetermined value or more, the method considers that the lifting of the rear wheel has occurred, and makes the reference speed follow a speed VRM. The speed VRM is a wheel speed calculated in accordance with the following formula: VRM=&agr;VRL+(1−&agr;)VRH (0<&agr;<1), where a character VRL indicates the slowest wheel speed, and a character &agr; indicates a default.

Abstract: To provide a technique capable of detecting lifting of a rear wheel of a two-wheeled vehicle correctly and rapidly. An estimated vehicle speed is generated by selecting the larger one of wheel speed Vf, Vr of a rear wheel and a front wheel, and attention is paid to an estimated vehicle deceleration which is computed based on the estimated vehicle speed and it is judged that lifting of the rear wheel has occurred when a degree of lowering of the estimated vehicle deceleration is a predetermined value or larger.

Abstract: An electric control apparatus of a brake is provided with a second reservoir, in which a brake fluid is stored in advance, separately from a control device of a brake hydraulic pressure. The second reservoir communicates with a pump, which is an original component of the control device, on the side of a suction opening of the pump through a second liquid passage equipped with a first on-off valve. A first liquid passage is equipped with a second on-off valve. The pump is operated with the first on-off valve being opened to supply a brake hydraulic pressure corresponding to the quantity of an operation of a brake pedal in a sate in which the second on-off valve is closed to a wheel cylinder as an electric control mode of a brake hydraulic pressure of an electronic control unit.

Abstract: In a brake control method for a motorcycle which includes a front master cylinder, front wheel cylinders hydraulically connectable to the front master cylinder, a rear master cylinder, a rear wheel cylinder means hydraulically connectable to the rear master cylinder and a hydraulic pressure pump, when only the front master cylinder is operated, brake pressure fluid is supplied to the front wheel cylinders, the fluid pressure pump is driven to supply discharging pressure fluid to the rear wheel cylinder and, when only the rear master cylinder is operated, brake pressure fluid is supplied only to the rear wheel cylinder.

Abstract: An electric control apparatus of a brake is provided with a second reservoir, in which a brake fluid is stored in advance, separately from a control device of a brake hydraulic pressure. The second reservoir communicates with a pump, which is an original component of the control device, on the side of a suction opening of the pump through a second liquid passage equipped with a first on-off valve. A first liquid passage is equipped with a second on-off valve. The pump is operated with the first on-off valve being opened to supply a brake hydraulic pressure corresponding to the quantity of an operation of a brake pedal in a sate in which the second on-off valve is closed to a wheel cylinder as an electric control mode of a brake hydraulic pressure of an electronic control unit.