Disclosed herein is a hydraulic master cylinder body having a bore defined at least in part by a bore wall, wherein the bore wall includes an opening for hydraulic fluid to be passed into the bore, and a piston assembly situated at least substantially in the bore, the assembly having a piston with a piston body and at least one cup seal situated substantially around the piston body, the cup seal situated adjacent to the bore wall so as to be in sealing engagement therewith, and a back-up ring that is situated about the piston body, wherein the back-up ring is positioned to at least partially cover a portion of the cup seal that is adjacent to the bore wall and to prevent at least a portion of the cup seal from contacting the bore wall and the opening for hydraulic fluid during piston actuation.

Disclosed herein is a hydraulic master cylinder body having a bore defined at least in part by a bore wall, wherein the bore wall includes an opening for hydraulic fluid to be passed into the bore, and a piston assembly situated at least substantially in the bore, the assembly having a piston with a piston body and at least one cup seal situated substantially around the piston body, the cup seal situated adjacent to the bore wall so as to be in sealing engagement therewith, and a back-up ring that is situated about the piston body, wherein the back-up ring is positioned to at least partially cover a portion of the cup seal that is adjacent to the bore wall and to prevent at least a portion of the cup seal from contacting the bore wall and the opening for hydraulic fluid during piston actuation.

A master cylinder for a hydraulic brake system or clutch system, in particular of a vehicle steered by handlebars, in particular of a bicycle, includes a housing containing a piston chamber. The housing accommodates a piston slidable therein and a pressure chamber. A compensating chamber communicates with the pressure chamber through at least one compensating bore. The housing has an attachment portion for attachment to a handlebar tube and the compensating chamber extends to the attachment portion and has a separating member for separating the hydraulic fluid from a compensating volume. The attachment portion has a clamping part made and arranged to attach the separating member to the attachment portion.

A master cylinder for a hydraulic brake system or clutch system, in particular of a vehicle steered by handlebars, in particular of a bicycle, includes a housing containing a piston chamber. The housing accommodates a piston slidable therein and a pressure chamber. A compensating chamber communicates with the pressure chamber through at least one compensating bore. The housing has an attachment portion for attachment to a handlebar tube and the compensating chamber extends to the attachment portion and has a separating member for separating the hydraulic fluid from a compensating volume. The attachment portion has a clamping part made and arranged to attach the separating member to the attachment portion.

A brake system comprises a reservoir; a brake pedal; a master cylinder including a first master chamber, a second master chamber, a first master piston, and a second master piston; a first hydraulic circuit including at least one first hydraulic wheel brake; a second hydraulic circuit including at least one second hydraulic wheel brake; and a hydraulic pressure supplier including an actuator for pressurizing the first hydraulic circuit and the second hydraulic circuit depending on an operation of the brake pedal in a normal operating mode. The master cylinder further comprises a locking chamber and an elastic pedal feel element arranged in the first master chamber to be in contact with the first master piston and the second master piston for generating a pedal force when the brake pedal is operated while the second master piston is locked in the normal operating mode.

A bicycle control device includes a housing member, a shift-operating mechanism, a hydraulic fluid pressure generator and a control lever member. The housing member has an attachment part for attachment to a handlebar, and a grip part extending longitudinally between first and second ends of the grip part. The shift-operating mechanism is coupled to a shifting device by a control cable. The hydraulic fluid pressure generator has a cylinder, a piston movably disposed within the cylinder to generate fluid pressure for controlling a braking device, and a rod part coupled to the piston. The control lever member has a cam member arranged to actuate the rod part, and a first operating lever coupled to the cam member. The first operating lever is pivotal around a first axis relative to the housing member and actuates the cam member by pivoting around the first axis.

A bicycle control device includes a housing member, a shift-operating mechanism, a hydraulic fluid pressure generator and a control lever member. The housing member has an attachment part for attachment to a handlebar, and a grip part extending longitudinally between first and second ends of the grip part. The shift-operating mechanism is coupled to a shifting device by a control cable. The hydraulic fluid pressure generator has a cylinder, a piston movably disposed within the cylinder to generate fluid pressure for controlling a braking device, and a rod part coupled to the piston. The control lever member has a cam member arranged to actuate the rod part, and a first operating lever coupled to the cam member. The first operating lever is pivotal around a first axis relative to the housing member and actuates the cam member by pivoting around the first axis.

A brake unit (1) includes: a master cylinder (2) unit which is fixed to a vehicle body, and which includes a master cylinder (2b) that is received within a first housing (20), and that is arranged to be interlocked with a brake pedal; and a pump unit (3) which is arranged to be driven by a motor (3), and which includes a second housing (30) within which a pump arranged to increase a wheel cylinder pressure is received, the master cylinder unit (2) and the pump unit (3) being integrally fixed through a mount (6) which is an elastic member.

A brake unit (1) includes: a master cylinder (2) unit which is fixed to a vehicle body, and which includes a master cylinder (2b) that is received within a first housing (20), and that is arranged to be interlocked with a brake pedal; and a pump unit (3) which is arranged to be driven by a motor (3), and which includes a second housing (30) within which a pump arranged to increase a wheel cylinder pressure is received, the master cylinder unit (2) and the pump unit (3) being integrally fixed through a mount (6) which is an elastic member.

A snow vehicle having a combined brake and clutch handle is herein disclosed. Further, the snow vehicle can include a controller for managing operation of the snow vehicle, including shifting and engine management regiments, which can be selected by the operator depending upon operator preferences. Additionally, the snow vehicle can include an engine cooling heat exchanger for cooling liquid which is circulated through the engine.