Starter to start an internal combustion engine through the intermediary of a belt

A starter (1) for initiating an internal combustion engine via a belt (5) connecting a starter and the motor comprises an electric motor (6) and an output shaft (8) connected to a drive pulley (2) via a one-way clutch (9). The output shaft is formed separately from a motor shaft (6a) so that the belt tension force is not directly transferred to the motor shaft. A diameter of the motor shaft (6a) is made smaller, for supporting a solar reduced dimensions (10) constituting a speed reduction mechanism planetary gear (7) and to improve thereby a torque rotation of the motor. The one-way clutch to which the drive pulley is connected may be attached to the output shaft by screw-coupling means.