My novice opinion is dirt in the needle and seat. Pull the top off and blow it /clean it out. Easy to do without carb removal, instructions online. Takes about 30min including checking float levels. Just remember 1/4" to the GASKET when checking floats. Had to do this two weeks ago and it was super simple. Only takes a few particles to cause an issue.
BTW. .The bolts on top are Torx.