A hub for a bicycle wheel having a hub body rotationally mounted on a central hollow shaft by means of bearings mounted on the shaft, the hollow shaft adapted to receive a quick release axle which projects beyond both ends of the axle. The shaft has three distinct portions, two end pieces and a central portion made of a material having a lower density than the end pieces, the end pieces being fitted to each end of the central portion, the end pieces having bearing surfaces for the bearings, and at least one of the end pieces having a threaded portion, respectively, for a nut for axially tightening the bearings.