My brand new (399 miles
The Yamaha vino is absolutely new, so this rare , but yes this sudden quit problems occurs , due to few possibilities.-------
1) the fuel has dirt contaminants in it and when it passes from fuel filter, that dirt contaminant clog/ block the flow of fuel foe few seconds and engine surges for it and at last quit.--------
2) Another problem is fuel loosing its connection to battery.Some connections related to fuel pump gets very little loose, but not disconnected.--------
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But as you mentioned in your question that " when this problem occurred,I could still hear the motor and It didn't respond when I gave it gas , this indicates that some dirt caused the fuel filter to get clogged or fuel pump nozzle to get clogged, and due to this it was not responding to the gas, and you were able to hear motor running.--------
But once this dirt got cleared, the problem is now not noticed.----------
So if again in few days if you notice same problem, then get your filter and fuel pump cleaned.----
then check, this will help.Thanks.Helpmech.