Eli5: Why do speed wobbles happen on bicycles travelling around 40mph or higher?

Question

Eli5: Why do speed wobbles happen on bicycles travelling around 40mph or higher?

In: 8

Answer 1

Also a matter of weight distribution; which usually results from poor geometry or design. There’s a video somewhere on YT that shows differences in stability at speed between a setup with weight centered and a setup with weight too far back. With the weight too far back it creates a pendulum effect from the rear that causes instability at the front.

In the case of a bike or motorcycle the rear end won’t necessarily go swinging out of control like you’ll see in a trailer setup but you’ll still get the instability on the front end.