Take the flame arrestor off the carb and look down into the carb throat (Engine not running) and have someone work the throttle lever. There should be a squirt of gasoline anytime the throttle lever is moved toward the open position. (Accelerator pump). Chances are the pump is bad, or isn't providing enough of a squirt to prevent stalling unless the throttle is moved very slowly. It sounds like it's time for a carburetor rebuild.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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