Second Generation New features were added to the next model. The second generation had a new throttle worm drive and mounting arrangement. The reed valves were added to the fixed partition. The worm gear drove the throttle to vary its length.Throttles are shown on the left half, in the open position, the throttle project into the combustion chamber and reduces its volume.The G2 fixed partition was two plates screwed together. The recessed area formed a channel and the round hole was the opening into the supercharger or secondary expansion chamber.Left side with supercharger and secondary expansion chamber cylinders.Reed valves (one-way valves) are visible.The reed valves are thin stainless flaps that cover the ports in the fixed partition. They are on both side of the fixed partition. One side is the supercharger and the other is the secondary expansion chamber.