found this joke kinda funny A dirt bike mechanic was taking a cylinder off a bike, when he was introduced to a world-famous heart surgeon. The mechanic said, "Hey Doc can I ask you a question?"
The famous surgeon said “Sure!” The mechanic, wiping his hands on a rag, asked, "So Doc… I open this engine up, take valves out, fix 'em, put in new parts, and when I’m done it’ll work just like a new one. So how come you get so much more money than me, when you and I are doing basically the same work?"
The surgeon looked the mechanic in the eye, smiled, and said, "Try doing it with the engine running!