Of Airhead engines of course...well the music/words are OK, too. There was a link to a video put together as part of a recent Georgia Airheads rally. This was an entry into the Airheads Beemer Club anthem contest. Look close, you might see a bike that you recognize!!
https://www.youtube.com/watch?app=desktop&v=Y-FDB-ecrRk
https://www.youtube.com/watch?app=desktop&v=Y-FDB-ecrRk