Bicycle with assist engine

DETAILED DESCRIPTION This invention is adapted to be embodied in an engine assisted, manually powered vehicle.
The vehicle comprises a body assembly that is adapted to accommodate at least one rider.
A propulsion device is provided for propelling the vehicle.
A manual operator receives manual force inputted from the rider for driving the propulsion device.
The manual operator is configured such that the force applied by the rider varies cyclically during a force application mode by the operator from a minimum value to a maximum value and back to a minimum value.
An internal combustion engine is also provided for the vehicle.
The internal combustion engine is coupled to the propulsion device for driving the propulsion device.
The engine has a control for varying the output of the engine.
A force sensor senses the force applied by the rider to the manual operator and outputs a control signal.
A drive coupling couples the output from the force sensor to the engine control for providing an engine assist to the manual operator of the propulsion device in response to the degree of manual force applied.
Means are provided for selectively modifying the connection between the force sensor output and the engine control for effecting changes in the amount of engine assist applied to the propulsion device.
In accordance with one feature of the invention, the modification of the connection between the force sensor output and the engine control reduces the change in rate of engine control in response to a rapid change in the force output from the sensor.
In accordance with another feature of the invention, the vehicle is also provided with a manually operated brake.
The coupling between the force sensor output and the engine control is disconnected when the brake is actuated for precluding engine assist when the brake is applied.