Abstract: A hydraulic brake mechanism is mountable to a bicycle handlebar. The hydraulic brake mechanism includes a housing having a base portion and an extension portion, the base portion including first and second ends, the base portion including a handlebar clamp at the first end, the base portion extending generally horizontally and the extension portion extending forwardly of the base portion at the second end and angled generally upwardly from the base portion when the hydraulic brake mechanism is mounted to the bicycle handlebar, the housing sized and shaped to be grasped by a user's hand, the housing having a fluid outlet port in the extension portion. The hydraulic brake mechanism may include a fluid line attached to the fluid outlet port and disposed in a groove formed along a length of the extension portion and the base portion of the housing.

Abstract: A hydraulic brake mechanism is mountable to a bicycle handlebar. The hydraulic brake mechanism includes a housing having a base portion and an extension portion, the base portion including first and second ends, the base portion including a handlebar clamp at the first end, the base portion extending generally horizontally and the extension portion extending forwardly of the base portion at the second end and angled generally upwardly from the base portion when the hydraulic brake mechanism is mounted to the bicycle handlebar, the housing sized and shaped to be grasped by a user's hand, the housing having a fluid outlet port in the extension portion. The hydraulic brake mechanism may include a fluid line attached to the fluid outlet port and disposed in a groove formed along a length of the extension portion and the base portion of the housing.

Abstract: A hydraulic brake mechanism is described including a housing. A master cylinder assembly is disposed within the housing, and the master cylinder assembly includes a fluid chamber. The fluid chamber includes a first chamber portion having a first diameter and a second chamber portion having a second diameter, with the first diameter greater than the second diameter. The fluid chamber includes a transition region between the first and second chamber portions. The mechanism includes a piston assembly having a piston disposed within the fluid chamber. A first seal is configured to sealingly engage between the first chamber portion and the piston, and a second seal is configured to sealingly engage between the second chamber portion and the piston. The mechanism includes an outlet port extending from the fluid chamber from or adjacent the transition region.

Abstract: A hydraulic brake mechanism is described including a housing. A master cylinder assembly is disposed within the housing, and the master cylinder assembly includes a fluid chamber. The fluid chamber includes a first chamber portion having a first diameter and a second chamber portion having a second diameter, with the first diameter greater than the second diameter. The fluid chamber includes a transition region between the first and second chamber portions. The mechanism includes a piston assembly having a piston disposed within the fluid chamber. A first seal is configured to sealingly engage between the first chamber portion and the piston, and a second seal is configured to sealingly engage between the second chamber portion and the piston. The mechanism includes an outlet port extending from the fluid chamber from or adjacent the transition region.

Abstract: A hydraulic brake mechanism is described including a housing. A master cylinder assembly is disposed within the housing, and the master cylinder assembly includes a fluid chamber. The fluid chamber includes a first chamber portion having a first diameter and a second chamber portion having a second diameter, with the first diameter greater than the second diameter. The fluid chamber includes a transition region between the first and second chamber portions. The mechanism includes a piston assembly having a piston disposed within the fluid chamber. A first seal is configured to sealingly engage between the first chamber portion and the piston, and a second seal is configured to sealingly engage between the second chamber portion and the piston. The mechanism includes an outlet port extending from the fluid chamber from or adjacent the transition region.

Abstract: A hydraulic brake mechanism is described including a housing. A master cylinder assembly is disposed within the housing, and the master cylinder assembly includes a fluid chamber. The fluid chamber includes a first chamber portion having a first diameter and a second chamber portion having a second diameter, with the first diameter greater than the second diameter. The fluid chamber includes a transition region between the first and second chamber portions. The mechanism includes a piston assembly having a piston disposed within the fluid chamber. A first seal is configured to sealingly engage between the first chamber portion and the piston, and a second seal is configured to sealingly engage between the second chamber portion and the piston. The mechanism includes an outlet port extending from the fluid chamber from or adjacent the transition region.

Abstract: A hydraulic brake mechanism is described including a housing. A master cylinder assembly is disposed within the housing, and the master cylinder assembly includes a fluid chamber. The fluid chamber includes a first chamber portion having a first diameter and a second chamber portion having a second diameter, with the first diameter greater than the second diameter. The fluid chamber includes a transition region between the first and second chamber portions. The mechanism includes a piston assembly having a piston disposed within the fluid chamber. A first seal is configured to sealingly engage between the first chamber portion and the piston, and a second seal is configured to sealingly engage between the second chamber portion and the piston. The mechanism includes an outlet port extending from the fluid chamber from or adjacent the transition region.

Abstract: A hydraulic brake mechanism is described including a housing. A master cylinder assembly is disposed within the housing, and the master cylinder assembly includes a fluid chamber. The fluid chamber includes a first chamber portion having a first diameter and a second chamber portion having a second diameter, with the first diameter greater than the second diameter. The fluid chamber includes a transition region between the first and second chamber portions. The mechanism includes a piston assembly having a piston disposed within the fluid chamber. A first seal is configured to sealingly engage between the first chamber portion and the piston, and a second seal is configured to sealingly engage between the second chamber portion and the piston. The mechanism includes an outlet port extending from the fluid chamber from or adjacent the transition region.

Abstract: A brake actuation assembly for a hydraulic brake system of a handlebar-steered vehicle, the brake actuation assembly including a housing mountable to a handlebar of the vehicle and having a chamber formed therein. A piston assembly is received and axially guided within the chamber. A linkage is pivotally attached to the housing and the piston assembly and a lever blade is connected to the linkage to effect movement of the linkage, wherein movement of the linkage produces a variable rate of travel of the piston assembly relative to the travel of the lever blade.