Right after three and before two tap the 'A' button, right after two and before one tap the 'B' button, right after one and before go tap the 'A' button
At the start of the race, between countdown from 3 to 2 rev your boat up about halfway, then let go to let it go back down. When it is all the way back right at 1 rev it up again and hold it until the race starts. If you did it you will start with a nine second boost. It may take some practice, but it works for all boats.
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