You can try running the motor with slightly higher fuel pressure, but you're getting into iffy territory. If the electric fuel pump is over running the stock needles and seats, you have three solutions.
1) Open your fuel pump, and play with the internal regulator. This may be a trial and error kind of thing, which will waste lots of time and effort, and may solve nothing. Also, may void your warranty.
2) Get a pressure regulator, and place it in line somewhere. Get quality stuff, don't waste your money on a cheap regulators, as they act more like volume restrictors.
3) Replace the original needles and seats with after market \"ball type\" needles and seats. I prefer this idea, as it leaves the pressure on the high side. Also gives you a reason to open the carbs and inspect the floats.
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