Abstract: A drive assembly for a two-wheeled vehicle, wherein a closed chain is guided around a drive pinion and a sprocket for output. The chain is formed by pins, on each a bush rotatable about the center longitudinal axis of the pin, a roller provided on each bushing, for rotation around the bushing and has play, and the pins being connected to each other at two opposite ends by means of plates. The outer surface of the bushings and the rollers is coated with pure ta-C, having no further chemical elements except for unavoidable trace elements resulting from production in a PVD method. An Ra roughness between 0.03 ?m and 0.2 ?m and/or an Rz roughness between 0.3 ?m and 2 ?m is adhered to the surface of the coatings. The surfaces of the pinion and the sprocket in contact with the rollers do not have a coating of diamond-like carbon.

Abstract: A drive assembly for a two-wheeled vehicle, wherein a closed chain is guided around a drive pinion and a sprocket for output. The chain is formed by pins, on each a bush rotatable about the center longitudinal axis of the pin, a roller provided on each bushing, for rotation around the bushing and has play, and the pins being connected to each other at two opposite ends by means of plates. The outer surface of the bushings and the rollers is coated with pure ta-C, having no further chemical elements except for unavoidable trace elements resulting from production in a PVD method. An Ra roughness between 0.03 ?m and 0.2 ?m and/or an Rz roughness between 0.3 ?m and 2 ?m is adhered to the surface of the coatings. The surfaces of the pinion and the sprocket in contact with the rollers do not have a coating of diamond-like carbon.

Abstract: A method for a defined surface treatment of a first carbon coating applied to a surface of a component The first carbon coating is brought into touching contact with at least one second carbon coating that is formed on a surface of a tool or second component and the two carbon coatings are moved relatively with one another so that the first carbon coating is smoothed by the second carbon coating. The first carbon coating and/or the second carbon coating are formed from a-C (amorphous carbon) or ta-C (tetrahedrally bonded amorphous carbon).

Abstract: The present invention relates to a method for a defined surface treatment of a first carbon coating (1) applied to a surface of a component (2). In this process, the first carbon coating (1) is brought into touching contact with at least one second carbon coating (3) that is formed on a surface of a tool (4) and the two carbon coatings (1, 3) are moved relatively in parallel with one another so that the first carbon coating (1) is smoothed by the second carbon coating (3). The first carbon coating (1) and/or the second carbon coating (2) are formed from a-C or ta-C.

Abstract: A method and system for coating the functional surfaces of symmetrically serrated components, in particular the tooth flanks of gears, includes a coating source emitting coating material in the form of electrically charged particles in the direction of a revolving component. A high-quality functional surface coating of the component is achieved in that a shield is arranged in the beam path between the component and the coating source transversely to the irradiation direction, which shields the component from the coating beam in a contour area with a functional surface orientation inclined flatly with respect to the irradiation direction.

Abstract: The invention relates to methods of working surfaces of a coating made of hard carbon such as —C or ta-C. In accordance with the object set, a smoothing of the surface of such a coating should be achieved with a low effort and low costs and a working of contoured surfaces should be achieved. In accordance with the invention, bristle-like or plate-like elements made of a metal and connected to a rotating element are brought into point-like or linear contact with the surface of the coating. These bristle-like or plate-like elements are moved along the surface and the surface is thus smoothed.