Check for any vacuum leak, such as a boot issue as mentioned. If you find nothing, pull the carbs and clean them well. You might have dislodged some trash in a bowl and stopped up your pilot/idle circuit.
"I'd like to meet the joker who had the nerve to call this a road!"
-- Walter Sigmann
"Loud tires save lives."
Facebook Page: https://www.facebook.com/brad.horn.9