Well if it is anything like a UK Honda MB50 then I would look to the carb, airbox throat and a restricted exhaust. Sprockets might be an issue too. Upchange all that and the bike would come alive for you. As with the carb I have no idea what and where to start with jetting. Maybe contact EACC over there and give a shout out to Mark Daniels. Good luck, nice wee bike by the way.
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