This happened last Summer and it wasn't an Airhead but I think inspiring. I was passing by a neighborhood, lots of stop signs, going down this hill and coming the other way was a loud obnoxious motorcycle of some sort. Older. Being ridden by a kid, youngster, but they are all younger than me. He killed it at the 4 way stop in front of me and was trying to push the monster off to the side to get out of traffic. I pulled over and offered out the window to help. He said,"It's nothing. Does this all the time when it's cold. Norton's are a Bitch when cold.". "Gotta hit the tickler a bunch of times." And he proceeded to punch down on the tickler 10 times or so. Jumping around. The bike now on the side stand. He jumps on the kick starter, a couple of times, and it roared to life. Some more adjustment. Put the helmet back on. And off he thundered.
Rat bike Norton. I sometimes think they have all the fun. But I think we get to do more miles and I can even get to get on the freeway on a good day.
Bill is right about the gaskets. They get sucked it or blown out or something. Blue Loctight on the screws helps.