From a song-by-song interview with the AV Club:
That’s the song that starts with an object. I was trying to come up with—you know, American songwriters have it so easy. You just mention a Cadillac, and you’ve got half a song title. Do you know what I mean? Mention a town—well, obviously not Scranton, New Jersey, but if you mention Abilene or something, that’s half a song title. And “Abilene Cadillac,” that’s a whole song title. I can hear the song right now! [Laughs.] But if you come from Britain, it’s harder, because the place names aren’t as romantic. They don’t have the association with popular song that American place names do. And objects aren’t as romantic, because they haven’t been used in songs over the years and don’t have that kind of reverberation in people’s minds. So I was trying to come up with kind of an object that would have some romance to it. And the Black Lightning motorcycle was that object.