My dog used to chase people on a bike a lot. It got so bad I had to take his bike away.
Why this joke works
Who Is Riding the Bike?
The first sentence encourages listeners to picture a dog chasing cyclists, because “people on a bike” seems to describe the people. Taking away “his bike” reveals that the dog was the rider all along. Deliver the setup as a familiar complaint about an energetic pet and do not stress “on a bike.” Pause briefly after “so bad,” then keep the solution matter-of-fact. The punchline works by assigning the bike to an unexpected owner, so extra explanation would only slow down the revised picture.
A closer look
The Possessive Pronoun Reassigns the Whole Scene
The first sentence places “on a bike” immediately after “people,” so normal reading attaches the bicycle to those being chased. The solution introduces “his” and makes the dog the rider instead. That one pronoun retrospectively changes posture, speed, and ownership without rewriting the setup. The matter-of-fact punishment treats canine cycling as established household behavior, completing the absurd image.
Fact behind the joke
A Loose Dog Is a Real Cycling Hazard
NHTSA bicycle-safety material advises riders approached by a threatening dog to keep control, use a firm verbal command, and, if necessary, dismount and place the bicycle between themselves and the animal while backing away. Riders should not try to outrun or hit the dog. In reality, the bike can serve as protection—the reverse of the dog owning it.