Friction ring-type transmission for a vehicle operable using motor power and/or pedal power, having a crankshaft for pedal cranks (102, 103), in particular for an electric bicycle, wherein - the friction ring-type transmission has an inner friction ring and an outer friction ring and at least one rotatable double-cone roller which is arranged on a roller carrier and which, during a transmission of torque via the friction ring-type transmission, is in frictional engagement with the inner friction wheel and the outer friction ring in each case under the action of a contact-pressure force, - wherein, in a force flow path from the inner friction ring to the outer friction ring, there is arranged a force return device for transmitting contact-pressure force from one friction ring (20, 26) to the other friction ring (20, 26), wherein one of the friction rings (20, 26) is arranged rotationally conjointly in relation to the force return device and the other friction ring (26, 20) is arranged rotatably in relation to the force return device, and - the friction ring-type transmission has an adjusting device for the transmission ratio, and said adjusting device is movable along an adjustment travel which runs in the direction of a central axis of the friction rings (20, 26), and - the roller carrier and the adjusting device and at least one portion of a housing of the friction ring-type transmission are arranged so as not to rotate, characterized in that - the adjusting device simultaneously runs around a central axis of the roller carrier over less than 360 degrees, - the adjusting device runs through the portion of the housing, and - the adjusting device is fixedly connected to the roller carrier, such that an actuation of the adjusting device directly displaces the roller carrier in an axial direction, wherein the adjusting device has no adjusting thread. - the friction ring-type transmission has an inner friction ring and an outer friction ring and at least one rotatable double-cone roller which is arranged on a roller carrier and which, during a transmission of torque via the friction ring-type transmission, is in frictional engagement with the inner friction wheel and the outer friction ring in each case under the action of a contact-pressure force, - wherein, in a force flow path from the inner friction ring to the outer friction ring, there is arranged a force return device for transmitting contact-pressure force from one friction ring (20, 26) to the other friction ring (20, 26), wherein one of the friction rings (20, 26) is arranged rotationally conjointly in relation to the force return device and the other friction ring (26, 20) is arranged rotatably in relation to the force return device, and - the friction ring-type transmission has an adjusting device for the transmission ratio, and said adjusting device is movable along an adjustment travel which runs in the direction of a central axis of the friction rings (20, 26), and - the roller carrier and the adjusting device and at least one portion of a housing of the friction ring-type transmission are arranged so as not to rotate, characterized in that - the adjusting device simultaneously runs around a central axis of the roller carrier over less than 360 degrees, - the adjusting device runs through the portion of the housing, and - the adjusting device is fixedly connected to the roller carrier, such that an actuation of the adjusting device directly displaces the roller carrier in an axial direction, wherein the adjusting device has no adjusting thread.