Bob: My car doesn't have a speedometer.　　Rob: Then how do you know how fast you're going?

　　Bob: Well, when I'm driving at 15 miles an hour, the fenders rattle; at 25 miles an hour, the windows rattle; and at 30, the motor starts knocking-and that's as fast as it'll go.

Obviously he can drive without a speedometer.

By the way, I like the English jokes you offered.