My son has this totally awesome “exhaust” pipe on his bike that I covet. It’s really a resonator for the classic baseball-card-in-the-spokes trick. It makes a terrific racket, and gets people to move out of the way without necessitating a honk on your horn. I decided to build my own, using a recycled beverage bottle. Armed with a Dremel Rotary Tool, a bottle of energy drink, and a depleted gift card, I set out to make my own soda bottle bike exhaust.