The Incredibly Counterintuitive Physics of Bicycle Turns

Derek Muller of Veritasium worked with Rick Cavallaro of the Blackbird Wind Powered Vehicle to create a very difficult bicycle with steering that can be remotely locked to show how in order to turn in a certain direction, a person must first turn in the opposite direction.

If you could ride this bicycle, you would find it’s impossible to turn left without first steering right and it’s impossible to turn right without first steering left. This seems wrong. …

This incredibly counterintuitive concept is performed intuitively on a daily basis. This particular bike locked the steering on the right side and then asked participants to try to make a left turn. The results, while amusing, prove their point. Unlike a car, which requires no counter-steering to make a turn, a bicycle requires balance as well as direction.

But the difference with a bicycle is steering doesn’t just affect the direction you’re headed; it also affects your balance. Imagine you want to make a right turn so you steer the handlebars to  he right. What you’ve done is effectively steered the bike out from under you. So now you’re leaning to the left and the ground puts a force on the bike to the left so the only way not to fall is to steer the bike to the left. You have made a left turn.

Mueller was inspired by a video by Minute Physics which explains how bicycles work.