This torque transmission mechanism (A) for an internal combustion engine, adapted to transmit a starting torque from a starter motor to a crankshaft (4) of the internal combustion engine, comprises a ring gear (2) that transmits the starting torque, a one-way clutch (8) disposed between the ring gear (2) and the crankshaft (4), a bearing (6) including a first ring (7) coupled in rotation with the gear ring (2) and a second ring (62) coupled in rotation with the crankshaft (4) and a front plate (10) for coupling in rotation the crankshaft (4) with the one-way clutch (8). The front plate (10) is coupled in rotation with the crankshaft (4) via the second ring (62) of the bearing (6), by welding along a direction (F1) parallel to a central axis (X-X') of the second ring (62) of the bearing (6).