An electric motor or generator system comprising a stator, a rotor, a first bearing, a first coupling device and a second coupling device, wherein the second coupling device includes a first coupling element arranged to be coupled to a vehicle and a second coupling element coupled to the rotor with a second bearing mounted between the first coupling element and the second coupling element to allow the rotor to rotate relative to the vehicle, wherein the first bearing is mounted between a surface of the stator and a surface of the rotor or the second coupling element to allow the rotor to rotate relative to the stator and the first coupling device is arranged to substantially preventing movement of the stator relative to the first coupling element in a first degree of freedom while allowing movement of the stator relative to the first coupling element in at least a second degree of freedom.