The motorcycle mechanic and the heart surgeon
A mechanic was removing a cylinder head from the engine of a motorcycle when he spotted a well-known heart surgeon in his shop. “Hey, Doc, can I ask you a question?”
The surgeon, a bit surprised, walked over to the mechanic working on the motorcycle.
The mechanic straightened up, wiped his hands on a rag and asked, “So Doc, look at this engine. I open its heart, take the valves out, fix ’em, put ’em back in, and when I finish, it works just like new. So how come I get such a small salary and you get the really big bucks when you and I are doing basically the same work?”
The surgeon paused, smiled, leaned over and whispered to the mechanic…
“Try doing it with the engine running.”
The image, via Wikipedia, is of Bela Lugosi as Dr. Paul Carruthers, the mad scientist protagonist in the 1940 horror film The Devil Bat. Nothing to do with motorcycles but, hey, that expression fits the story.