The invention relates to a hand-held chiselling machine tool 1 comprising a motor 5 and a pneumatic percussive mechanism 6 that is driven by the motor 5. The user can select between at least two idling rotational speeds by means of a selector switch 24. In the chiselling mode, a motor control unit 20 regulates a rotational speed of the motor 5 to a nominal rotational speed. This nominal rotational speed cannot be set by the user, but is predetermined with regard to an optimal efficiency for said percussive mechanism 6. The motor control unit 20 sets the rotational speed of the motor 5 to the selected idling rotational speed when the percussive mechanism 6 is idling. At least one of the selectable idling rotational speeds is greater than the nominal rotational speed.