Mine does the same thing but usually the back carb after it sits awhile. It is the needle and seat sticking. Next time if it does it, tap on the front of the carb and see if it quits. I had the gross-jet needle and seats in it awhile and did not have that problem but went back to stock units the last rebuild. I thnk it just sits awhile and sticks. If it gets run more regularly, It does not happen.
