Over 60mph most of a bike’s power is being used to push the air out of the way, so when you roll off the throttle the giant airbrake that is the rider quickly slows the bike. Unless you've a full streamliner fairing
The air around us is easy to forget, even when it lifts you and 150 tonnes of Jumbo up, up and away on your hols. Whatever you're doing now, there's a tonne or two of air weighing down on you, its molecules pulled down by gravity.
This is of great interest to F1 car-bores, because you can pinch this weight as ground effect to make Jenson and Hammy look like passengers in a giant Scalextric set. No good for bikes though, because the direction of the downforce changes when you lean over. Didn't stop MV trying in the 70s, mind..
