A bearing has an inner ring coaxial to and rotatable relative to an outer ring. A central bore of the inner ring accommodates a multi-sided shaft in at least two positions that are angularly offset relative to each other. Each position provides a different fit between the inner ring and the shaft. A preferred embodiment has a 12-pointed star-shaped bore defined by the superposition of two hexagons of slightly different scale, to accommodate a hexagonal shaft in either of two positions. The second position provides a tighter fit between the bearing and the shaft without requiring tighter manufacturing tolerances.
