Abstract: The invention relates to a homogeniser having an inlet leading into a homogenisation chamber, an outlet leading out of the homogenisation chamber, a stator and a rotor head generating shear forces together with the stator, wherein the stator and the rotor head are arranged in the homogenisation chamber, a rotor shaft connected to the rotor head, and a motor driving the rotor shaft. The homogeniser is characterised by a sleeve having an internal thread and rotatably connected to the rotor head, which sleeve screws onto an external thread formed on the rotor shaft in order to adjust the dimension of the gap between the stator and the rotor head, and a fixing means arrangement for fixing the sleeve on the rotor shaft.