Driving device for a two-wheeled bicycle driven by an electric motor, comprising: a first drive for providing a first driving force, an electric motor for providing a second driving force, a power takeoff configured to receive the first and/or second driving force(s) and to output same to at least one wheel that is to be driven of the bicycle, a force transmission means arrange between the first drive and the power takeoff, and a sensor arranged at the carrying side of the force transmission means and configured to generate sensor data as a function of a deflection of the force transmission means, the sensor being arranged to be in contact with the outer side of the carrying side of the force transmission means, wherein the sensor comprises a deflection device which is in contact with the carrying side of the force transmission means and cooperates with the force transmission means such that it is deflected when the carrying side of the force transmission means is tensioned, wherein the deflection device is deflectable in a swiveling manner, wherein the deflection device comprises a swiveling cantilever and an elastic element, wherein the cantilever is arranged to be rotatable at a stud disposed at the housing and, therefore, is arranged to be able to swivel at the housing at one end, and wherein the opposite end of the cantilever is in contact with the outer side of the force transmission means, wherein the elastic element is supported at a bearing provided at a housing, and wherein a force exerted on the elastic element increases as the deflection of the cantilever increases, wherein the elastic element comprises a piezo crystal, and wherein the first drive, the power takeoff, the force transmission means, and the sensor are arranged within a shared housing. a first drive for providing a first driving force, an electric motor for providing a second driving force, a power takeoff configured to receive the first and/or second driving force(s) and to output same to at least one wheel that is to be driven of the bicycle, a force transmission means arrange between the first drive and the power takeoff, and a sensor arranged at the carrying side of the force transmission means and configured to generate sensor data as a function of a deflection of the force transmission means, the sensor being arranged to be in contact with the outer side of the carrying side of the force transmission means, wherein the sensor comprises a deflection device which is in contact with the carrying side of the force transmission means and cooperates with the force transmission means such that it is deflected when the carrying side of the force transmission means is tensioned, wherein the deflection device is deflectable in a swiveling manner, wherein the deflection device comprises a swiveling cantilever and an elastic element, wherein the cantilever is arranged to be rotatable at a stud disposed at the housing and, therefore, is arranged to be able to swivel at the housing at one end, and wherein the opposite end of the cantilever is in contact with the outer side of the force transmission means, wherein the elastic element is supported at a bearing provided at a housing, and wherein a force exerted on the elastic element increases as the deflection of the cantilever increases, wherein the elastic element comprises a piezo crystal, and wherein the first drive, the power takeoff, the force transmission means, and the sensor are arranged within a shared housing.