There is described a shock absorber strut for a bicycle, comprising a piston (12), a cylinder (13) and a resilient element (20) positioned within the cylinder. The piston extends out of one end of the cylinder, and the other end of the cylinder is closed by a casing made up of two housing halves. Mounting bushings are integrally formed in the housing halves and on the piston end, respectively, for fixing the shock absorber to a bicycle frame. The piston (12) can be withdrawn from the cylinder (13) by a simple tension, without the use of tools.