A derailleur-based electronic transmission system for an electric bicycle, the system comprising: a wheel; a driven sprocket set coupled to the wheel via at least a first one-way clutch, the driven sprocket set comprising two or more concentric sprockets of different effective diameters; a drive chain configured to engage the driven sprocket set; an electronically controllable derailleur configured to move the drive chain among the two or more sprockets; a pedal crank configured to cause rotation of the driven sprocket set by providing a user pedal force to the driven sprocket set through at least a second one-way clutch and the drive chain; a motor configured to cause rotation of the driven sprocket set by providing an electromechanical force to the driven sprocket set through at least the drive chain; and an electronic controller configured to, responsive to a determination that a shift should occur at a time when neither the pedal crank nor the motor is causing rotation of the driven sprocket: operate the motor to rotate the driven sprocket at a rotational speed less than or equal to a current rotational speed of the wheel; and operate the derailleur to cause the shift to occur while the driven sprocket is being rotated by the motor, the electronic controller further configured to determine that the shift should occur by determining that a stop event is occurring, wherein determining that the stop event is occurring comprises monitoring, directly and/or indirectly, one or more of the following: a rotational speed of the wheel, a rotational speed of the pedal crank, a rate of deceleration of the rotational speed of the wheel, a braking force, a rate of translational deceleration, a pedal cadence, characterized in that the electronic controller is further configured to: estimate a remaining amount of revolutions of the wheel before the stop event completes; and operate the motor to rotate the driven sprocket at a rotational speed less than or equal to the current rotational speed of the wheel, but sufficiently fast to complete the shift within the estimated remaining amount of revolutions of the wheel. a wheel; a driven sprocket set coupled to the wheel via at least a first one-way clutch, the driven sprocket set comprising two or more concentric sprockets of different effective diameters; a drive chain configured to engage the driven sprocket set; an electronically controllable derailleur configured to move the drive chain among the two or more sprockets; a pedal crank configured to cause rotation of the driven sprocket set by providing a user pedal force to the driven sprocket set through at least a second one-way clutch and the drive chain; a motor configured to cause rotation of the driven sprocket set by providing an electromechanical force to the driven sprocket set through at least the drive chain; and an electronic controller configured to, responsive to a determination that a shift should occur at a time when neither the pedal crank nor the motor is causing rotation of the driven sprocket: operate the motor to rotate the driven sprocket at a rotational speed less than or equal to a current rotational speed of the wheel; and operate the derailleur to cause the shift to occur while the driven sprocket is being rotated by the motor, operate the motor to rotate the driven sprocket at a rotational speed less than or equal to a current rotational speed of the wheel; and operate the derailleur to cause the shift to occur while the driven sprocket is being rotated by the motor, the electronic controller further configured to determine that the shift should occur by determining that a stop event is occurring, wherein determining that the stop event is occurring comprises monitoring, directly and/or indirectly, one or more of the following: a rotational speed of the wheel, a rotational speed of the pedal crank, a rate of deceleration of the rotational speed of the wheel, a braking force, a rate of translational deceleration, a pedal cadence, characterized in that the electronic controller is further configured to: estimate a remaining amount of revolutions of the wheel before the stop event completes; and operate the motor to rotate the driven sprocket at a rotational speed less than or equal to the current rotational speed of the wheel, but sufficiently fast to complete the shift within the estimated remaining amount of revolutions of the wheel. estimate a remaining amount of revolutions of the wheel before the stop event completes; and operate the motor to rotate the driven sprocket at a rotational speed less than or equal to the current rotational speed of the wheel, but sufficiently fast to complete the shift within the estimated remaining amount of revolutions of the wheel.