Pusher motors have been around for about 100 years and worked pretty well. One of the most famous being the Briggs and Stratton Red Bug shown in the link below. If I built one, I would try to give it some caster so when I turned it would also and push the direction of my steering. Simple enough to make with one wheel and two connecting pivot pins on the rear of the surrey to handle uneven roads. Controls could simply be a throttle lever and a safety ignition kill switch quickly clamped on for easy access by the driver. A centrifugal clutch or torque-a-verter would handle idle and acceleration. Might add a cable operated brake for more stopping power. Small motorcycle or moped rear wheels with a built-on sprocket and brake drum would be a good candidate for a pusher build. Wichever way you go, it's a real challenge and sure to be copied by some of us. I can't wait to see your project get under way. Thanks for bringing this to the forum for us to enjoy with you.
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