Urgent help needed! Carb leaking fuel.

[luadraman]

Hi all, I had just set off from Calabar in Nigeria today to make my way to the border and stopped for a bite to eat only to return to my bike leaking fuel from the overflow hose (not a small drip either). I decided to head back to Calabar to get it sorted but haven't found a mechanic yet - apparently bikes were banned here!? Visa running out in a few days so even a quick fix to get me to the Cameroon capital next week will do.
Two days ago I had to bring the bike to a mechanic who cleaned the carb (there had been a lot of loud popping from the exhaust and the engine then died, spark plug was also black) which worked fine after that but maybe something was damaged? I've read other threads which mention needle etc but tbh I have only basic mechanical knowledge from working on diesel vans so know nothing about carbs!
Help much appreciated but be specific and assume I know nothing! Thanks...