My First mini bike was a Flexo Big Bear Scrambler and it had a MAC 6 engine and it had three carbs twin carbs on a Gem reed manifold and a single carb in the stuffer. I did not keep it that way for long and went for a single flat back carb.
With the two strokes feed the fuel to a balanced and ported engine and all they will do is make more RPM . But at that point it is also up to the proper exhaust to extract that burned fuel and that is where most designs fail. That engine should be worth a fair amount of change on E-Bay I'll Start the bidding @ $10.00 LOL Steve