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How a Bicycle Works: Not Like We Thought

 by Keith Goetzman


Tags: bicycles, biking, research, physics, science and technology, Keith Goetzman,

Bike wheel shadow

What makes a bike stay upright? Many of us can repeat the conventional grade-school wisdom that the gyroscopic effect is the magical stabilizer of the spinning bike wheel—but scientists are finding that the physics of biking are much more complex than this, reports Science News. They are learning this in part by trying to knock over moving bikes.

A bicycle in motion, even riderless, can coast for long distances without falling. The bike-abusing researchers are learning that neither the gyroscopic effect nor another long-accepted explanation, the “trail effect,” entirely explains the bike’s stability. Writes Science News:

Bicycles, the team suggests, are more complicated than previously thought. While gyro and trail effects can contribute to stability, other factors such as the distribution of mass and the bike’s moment of inertia can play a role as well. Computer simulations that take all of these factors into account could lead to improved designs for folding bikes with small wheels or bikes that carry cargo, [scientist Andy] Ruina says.

So remember, bikers, whether you’re keeping it pure on a fixed-gear or geeking out on a slow-rolling “comfort” bike, many of the same physical forces apply. And as for the oft-maligned weird cousins of the bicycle world, recumbent bike riders? They are no less than the fearless test pilots of the future.

Source: Science News 

Image by Looking Glass, licensed under Creative Commons.