The connection of the fuel line to a Tillotson carb is notorious for air leaks try wrapping it again with 2 separate wire wraps also check the plastic cap for cracks under the nipple. Sometimes when fuel sits in a tank it can form goop in the bottom that will clog almost anything. Same thing if old fuel was sitting in the carb for long.
Another way out possibility, maybe a crank seal popped out or a reed is broke?
FAA certified jet engine and aircraft technician,
Nicholson Speedway class champion 2001,
Yamaha KT100 Service Center,
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