Master cylinder for a hydraulic actuation system for a handlebar-steered vehicle

Abstract

A master cylinder assembly for a hydraulic actuation system for a handlebar-steered vehicle. The master cylinder assembly generally includes a housing mountable to a frame member of the handlebar-steered vehicle and having a chamber including a fluid cavity with first and second fluid cavity regions. The first fluid cavity region is in fluid communication with the hydraulic actuation system. The housing includes discrete first and second housing portions. The first housing portion has first and second end portions. The first end portion of the first housing portion extends axially into the second fluid cavity region creating an annular gap radially outboard of the first end portion extending into the second fluid cavity region. The second end portion of the first housing portion is connected to the hydraulic actuation system. A piston assembly includes a piston slidably disposed within the fluid cavity. An actuator is operatively connected to the housing and operatively connected to the piston to slidably displace the piston between an open fluid circuit position permitting fluid flow between the first and second fluid cavity regions and a closed fluid circuit position blocking fluid flow between the first and second fluid cavity regions.