Old Man and his Moped

A very self-important young man goes out and buys what he believes is the best car available: a Porsche 911 Turbo. It is one of the fastest and most expensive cars in the world.
That night, he takes it out for a spin and, while doing so, stops at a red light. An old man on a moped (both looking about 90 years old) pulls up next to him. The old man looks over the sleek, shiny Porsche and asks, “What kind of car ya’ got there, sonny?”
The young man replies, “A Porsche 911 Turbo. It cost me $120,000.”
“That’s a lot of money,” replies the old man. “Why do they cost so much?”
“Because this car can do up to 180 miles an hour!” states the young man proudly.
The moped driver asks, “Can I take a look inside?”
“Sure,” replies the owner.
So the old man pokes his head in the window and looks around. Leaning back on his moped, the he says, “That’s a pretty nice car, all right!”
Just then the light changes, so the young guy decides to show the old man what his car can do. He floors it, and within 10 seconds the speedometer reads 120 MPH.
Suddenly, he notices a dot in his rear view mirror that seems to be getting closer! He slows down to see what it could be and suddenly, whhhoooossshhh! Something whips by him, going much faster!
“What on earth could be going faster than my Porsche 911 Turbo?” he wonders.
Then, ahead of him, he sees a dot coming toward him. Whoooooosh! It goes by again, heading the opposite direction! And, it almost looked like the old man on the moped!
“Couldn’t be,” thinks the guy. “How could a moped outrun a Porsche 911 Turbo?”
Again, he sees a dot in his rear view mirror! Whooooosh-BLAMMM! It slams into the back of his car.
The young man jumps out and finds the old man lying behind his car!
He leans over him and says, “You’re hurt bad! Is there anything I can do for you?”
The old man groans and replies, “Yes. Unhook my suspenders from your side mirror, please.”