Electric motor in a vehicle unit

The invention relates to an electrical vehicle power unit (10) with an electronically commutated drive motor (40) which has a permanently excited motor rotor (16), a motor stator (18) and a motor housing (50), wherein during assembly of the drive motor (40) the leading shaft end (26) of the motor rotor shaft (14) is threaded into a fixed shaft opening (24). The motor rotor shaft (14) is configured such that during assembly the leading shaft end (26) of the motor rotor shaft (14) comes into engagement with the shaft opening (24) before the permanent magnetic motor rotor (16) enters the magnetic effective range of the motor stator (18).