The way a 2 stroke works is right behind the carbs are reed valves, if you ever take a 2 stroke apart you will notice the crank had channels cut into it, the fuel has to have a realitivly stright shot to the cylinder. The vacume of the piston pulls the fuel from the carb onto that channel in the crank, then the applied forces sling that fuel into the cylinders to atomize. That would not be possible with only 1 carb. best I can tell. As far as 1 vs. 2 cylinders it is probably marginal as far as the difference. The bigger you go on the motor the additional cylinders provide a longer lasting motor. As in you example of a 40 HP Yamaha, they make a 2 cylinder version and a 3 cylinder version. They are heavier but have to work less to provide the same HP. If you notice the 1 cylinder in these small motors have a slightly higher gear ratio. I would think you would get a pinch more torque out of the 2 cylinder since you have more rotating mass.
Originally Posted by Capt Crunch
IF IT CAN'T BE FIXED WITH A HAMMER, ITS AN ELECTRICAL PROBLEM
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