A control device of a bicycle hydraulic brake, comprising a cylinder, a tank, a piston slidably mounted in the cylinder to move between at least one first rest position in which the cylinder and the tank are in fluid communication and at least one second position in which the piston interrupts the fluid communication between the cylinder and the tank, a stop device that acts directly or indirectly on the piston. The cylinder and the tank are filled with hydraulic fluid and the stop device can take up a storage and transportation configuration in which it arranges the piston in said at least one second position.

A hydraulic tank for a bicycle that has a compensation chamber within the tank. The tank also has a ventilation hole and a ventilation channel, which is in fluid communication with the ventilation hole, and has an inlet opening arranged on a side wall of the tank.

A piston assembly is provided for a human-powered vehicle. The piston assembly includes a main body, a primary seal and a secondary seal. The main body is configured to be movable from a rest position to an actuated position along an actuation direction in a cylinder bore. The primary seal includes a primary seal body arranged on the main body, the primary seal body being made of the first seal material. The secondary seal includes a secondary seal body arranged on the main body at upstream of the primary seal with respect to the actuation direction. The secondary seal body is made of a second seal material that is more elastic than the first seal material.

Embodiments include an off-road vehicle with a straddle seat, a plurality of ground engaging members, a prime mover and a frame having a removable frame portion overlying the prime mover, wherein at least a portion of the engine extends above at least a portion of the removable frame portion, and wherein at least a portion of the straddle seat extends over the removable frame portion and the prime mover.

A hydraulic disc braking system is disclosed. The system has a manually operated control device for a cyclist to issue a braking command. The system has a master cylinder assembly having a membrane dividing the hydraulic fluid tank into a variable volume filled chamber and a complementarily variable volume empty chamber. A membrane detector senses the presence of the membrane relative to a predetermined position in the tank and/or a meter measures the distance of the membrane from the ceiling of tank.

A diagnostic method for a bicycle hydraulic disc braking system, having a master cylinder assembly with a cylinder inside which a piston reciprocates against the action of a return spring. The master cylinder has a hydraulic tank with a bottom, a ceiling, and a membrane that divides the hydraulic tank into two chambers. The hydraulic tank is connected to the cylinder through the bottom. A metering device measures the distance between the membrane and the ceiling of the tank. The output signal of the metering device is evaluated to determine that operation is correct when the membrane temporarily approaches the ceiling by a predetermined extent range, or incorrect otherwise. A positive evaluation reflects the correct operating condition, and a negative evaluation reflects an incorrect operating condition.

A control device for a bicycle has a housing configured to be mountable to the bicycle and sized and shaped to be grasped by a user's hand and a battery receptacle positioned on the housing. The housing has a base portion and an extension portion. The base portion includes first and second ends, a downward facing side, an upward facing side, an inward facing side, an outward facing side, and a handlebar clamp disposed at the first end. A battery receptacle is positioned on a first side, which can be the downward facing side, of the base portion of the housing. An accessory port can be positioned on a second side of the base portion of the housing, different from the first side, and which can be the inward or outward facing side of the base portion of the housing.

An operating device comprises a base member and an operating member. The base member includes a base body and a mounting part. The mounting part includes a mounting contact surface contactable with a tubular part of the human-powered vehicle in a mounting state where the mounting part couples the base body to the tubular part of the human-powered vehicle. The base member includes a first contact surface and a second contact surface. The first contact surface is contactable with the tubular part of the human-powered vehicle in the mounting state. The first contact surface is spaced apart from the mounting contact surface in an axial direction. The second contact surface is contactable with the tubular part of the human-powered vehicle in the mounting state. The second contact surface is spaced apart from the mounting contact surface and the first contact surface in the axial direction.

A brake device for a vehicle with at least one wheel, wherein the wheel defines a rotational axis, with a brake body device for the transmission of a brake force to the wheel, with a concentric brake cylinder for the generation of the brake force. The brake cylinder has an inner housing part for radial support on a wheel axle of the wheel and an outer housing part for axial support on the brake body device. The two housing parts can be moved relative to one another, and a pressure chamber which runs around the rotational axis is formed between the two housing parts. The brake device has an insulation device for the thermal insulation of the brake body device in the direction of the brake cylinder. The insulation device is arranged at least axially between the outer housing part and the brake body device.

A control device comprises two brake master cylinders (13, 14), both of which may be operated simultaneously by the same single manual control lever (15), according to a combined or integral braking mode. A switching element (27), associated with the manual control lever (15), may exclude one (14) of the two brake master cylinders.