Abstract: A tooth of a pinion has a first flank extending across a face width of the tooth in an axial direction substantially parallel to a central axis of the pinion from a first axial end of the tooth to a second axial end of the tooth. The first flank has a first, convex crown profile shaped as an arc of a first circle with a first radius, and a first center of arc radius of the first flank is a point on the first flank located on a line perpendicular to the central axis of the pinion and passing through the center of the first circle. A second opposite and opposing flank of the tooth has a second, convex crown profile shaped as an arc of a second circle with a second radius, wherein a second center of arc radius of the second flank is a point on the second flank located on a line perpendicular to the central axis of the pinion and passing through the center of the second circle.