From Hells Angels: A Strange and Terrible Saga by Hunter S. Thompson, 1966
But with the throttle screwed on, there is only the barest margin, and no room at all for mistakes. It has to be done right… and that's when the strange music starts, when you stretch your luck so far that fear becomes exhilaration and vibrates along your arms. You can barely see at a hundred; the tears blow back so fast that they vaporize before they get to your ears. The only sounds are the wind and a dull roar floating back from the mufflers. You watch the white line and try to lean with it… howling through a turn to the right, then to the left, and down the long hill to Pacifica… letting off now, watching for cops, but only until the next dark stretch and another few seconds on the edge… The Edge… There is no honest way to explain it because the only people who really know where it is are the ones who have gone over. The others- the living- are those who pushed their luck as far as they felt they could handle it, and then pulled back, or slowed down, or did whatever they had to when it came time to choose between Now and Later. But the edge is still Out there. Or maybe it’s In. The association of motorcycles with LSD is no accident of publicity. They are both a means to an end, to the place of definitions.