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: 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 brake or clutch lever comprises a lever that pivots about an axis, a lever mounting structure from which the lever extends, and a thumbwheel having a cam thereon. The cam is disposed directly between the lever and the lever mounting structure. The thumbwheel rotates about an axis that is perpendicular to the axis of lever pivoting. Also provided is a method of adjusting a height of a brake or clutch lever. A grip portion of a brake or clutch lever is lifted away from a handlebar. A thumbwheel having a cam thereon is rotated about an axis that is perpendicular to a pivot axis of the brake or clutch lever. The brake or clutch lever is lowered toward the handlebar. A method of assembling a brake or clutch lever height adjuster is also provided.

Abstract: A disc brake rotor comprises an internally disposed splined surface defining a circular opening and including one or more axially disposed internal splines that are adapted to be received on external splines of a splined structure of a wheel hub, the surface including a non-continuity such as a cut-away portion of the surface into which independent splines are selectively actuable to align with the internal splines as a part of the surface to allow the rotor to be connected to or released from the hub without using any tools or the like. Preferably, the independent splines are finger actuable, and provide through a workpiece comprising a locking hammer of locking foot.