So I installed a LED light on the bike to replace the stock incandescent one, which by the way is a big improvement in light output but it was $30. While I was in there mucking around I was going to add on a flasher unit too, but lo and behold there are 3 freaking wires and not the two that I was expecting. The black is obviously the ground/return but which one is the actual brake light wire, red or blue? Any one have any ideas?

Check with a multimeter. The running light wire will put voltage across the multimeter when the key is on but no brake lever. The brake light wire will put voltage across the multimeter when the brake lever is pulled.

I had a feeling that was gonna be the answer, I just don't want to go buy one.

Ping CThunder-blue, he figured it out to put a flasher on my 300.

The brake light is the blue wire and the red light is the running wire.

Sweet, thanks. I'll get it installed this weekend and maybe try to upload a video of it. Got it pretty cheap from superbrightleds.com.