Here in Fort Wayne, if the only thing that is visible is the "glow" any color is legal...one of the TOP cops here says that if anything except the glow(ie. bulb or tube) is visible from the front or rear, it is illegal. The best thing to do is check with your local PD.Red lights on the front of a vehicle may not be legal, In some states red is for the rear of a vehicle. And blue is for Emergency vehicles, Some of the kids that but blue lights on their cars for looks, like blue led's where the windshied washers are, have been ticketed.
But my wing has a blue ring of fire-It was on there when I bought it, but I can't see it when I'm riding.
Next time I take the rotor covers off, I'll most likely remove the ring of fire,just something to go wrong or short out, sides I don't ride at night a whole bunch at night, and it doesn't show up much in daylight.