Why do Motorcycles drivers do this?
 

Why do Motorcycle drivers need to "REV" their engines for thirty minutes in their driveway at 7 am in the moring and not go anywhere? Are you people trying to be jerks or is it something mechanically neccesarry to do with the bike?

You should always warm the bike up before you ride it. But I doubt he does it for 30 min. I bet your exaggerating and just don't like bikes. I warm mine up in the summer for 2 or 3 min. and in the winter for 4 or 5 min. to get the oil flowing and the fuel system to work properly. Most bike are louder than cars and I know it can be annoying to neighbors so I always try to keep my warm to a minimum, especially in the morning or at night.

This is pretty much one of those DUHH...questions, however, I think you pretty much hit the nail on the head with the JERKS answer.

It's morning sometimes, there is no gas in the line, it's cold so the motorcycle stalls. I rev it to get it going once idle i don't rev it again.

I don't,as it wastes fuel and takes longer to warm up.Pointless and not good for the motor either.