I know this is going to sound crazy but I had the same thing. It ended up being my pants leg flapping! I couldnt believe it. I reached down and pulled it tight and it stopped.
Hope this helps.
Don't feel bad talon, I had a metal to metal noise on my FLSTC. It wasn't there when I wasn't moveing but started almost as soon as the bike was in motion. Looked and tightened for 2 days, found the problem on the 3rd day, chain from my wallet was hitting the metal rail that goes around the solo seat.:newsmile030: