Abstract: 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.

Abstract: A hydraulic brake actuator adapted to be mounted on a vehicle handlebar and hydraulically coupled to a brake mechanism. The brake actuator includes a brake base adapted to be secured to the handlebar, and a reservoir adapted to be coupled to the brake base and containing brake fluid, the reservoir having a bottom surface. The hydraulic brake actuator further includes a piston-cylinder assembly coupled to the reservoir, a brake lever movable relative to the brake base between a released position and an actuated position, and a locking pawl positioned to limit movement between the brake lever and the piston-cylinder assembly, the locking pawl being at least partially positioned directly below the bottom surface of the reservoir.

Abstract: 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.

Abstract: 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.

Abstract: A hydraulic brake actuator adapted to be mounted on a vehicle handlebar and hydraulically coupled to a brake mechanism. The brake actuator includes a brake base adapted to be secured to the handlebar, and a reservoir adapted to be coupled to the brake base and containing brake fluid, the reservoir having a bottom surface. The hydraulic brake actuator further includes a piston-cylinder assembly coupled to the reservoir, a brake lever movable relative to the brake base between a released position and an actuated position, and a locking pawl positioned to limit movement between the brake lever and the piston-cylinder assembly, the locking pawl being at least partially positioned directly below the bottom surface of the reservoir.

Abstract: 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.

Abstract: A disc brake assembly includes an improved pad holder for holding a brake pad in the brake assembly. The pad holder takes the form of a simple spring clip, preferably a wire form, that holds the rear surface of the pad tightly against the front surface of the piston or pistons of the associated caliper to prevent brake drag and brake rattle. The clip is simple and inexpensive to manufacture and can be easily installed without removing the disc or the caliper from the brake assembly. Indeed, the pad/pad holder subassembly can be removed from the brake assembly, without using any special tools, simply by imposing sufficient upward vertical retraction forces on the pad/pad holder subassembly to deflect the spring clip and to remove the pad holder from the pistons to which it is attached.