Currently running a 247cc, 84#, 15HP Nissan, carbureted, 2-stroke with a 1.85:1 gearcase, 8.5 pitch prop, at 5500 rpm's and 22 mph. Speed isn't my primary concern but I'd like to get into a lightweight, fuel injected, 4-stroke. Twin cylinders would be nice to keep the weight down but would go to...