Random speed boosts

mario-kart-8

When playing with friends, we all noticed that sometimes we'd get a random boost of speed seemingly out of nowhere, usually when we're trying to pass someone. Often it would screw us up by sending us off the track or sometimes help by letting us pass the opponents, but there seemed to be no pattern for when it happens.
What are the criteria/requirements for this random boost to happen?

Best Answer

Drafting, also known as slipstreaming, is a technique that allows for a short speed boost. If a player trails behind another racer for a certain period of time, the player's vehicle receives a temporary speed boost. If the position is held for about 3-5 seconds, the player will be surrounded in a blue wind with a modest speed increase. The boost lasts for about 3 seconds, or until the player hits a wall, obstacle, racer, or item. It can last as long as a Mushroom boost.

Screenshot from Mario Kart 8 of drafting effect:
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