Vibration in Rear when lightly breaking

I just changed my rear tire and put in new break pads. While driving this morning and breaking at speeds above 20 mph, I get a vibrating noise, sounds like a 2 stroke weed trimmer motor going. When I apply more pressure it goes away. I am guessing it is NOT a warped rotor because I do not feel any pulsating noise. I know the pads are not sticking because my average miles per hour went up on the ride here. I am guessing the rotor has some issues with its face and the new pads are not seating correctly when lightly applied. I do not so much mind changing the rotor, it's more about taking everything apart again. My questions is do I do nothing for about 200 miles and see if the pads seat themselves to the rotor? Do I try sanding the rotor, as other threads have suggested or do I stop whining and buy a new rotor?

PS just reviewed threads on break bleeding. In all the sites I have ever used this is by far the greatest site for information.

I would first make sure you have the pads installed correctly and seated in the caliper itself correctly, sometimes folks will not get the forward part of the pads seated into the retaining clip.

In this article, you can see a little how the pad fits into the forward clip.
https://www.st-owners.com/forums/showthread.php?101206-ST1300-Rear-Brake-Piston-Cleaning

If that's okay, then I'd give it a few miles as it does sound like new pads getting used to the rotor surface.

I know without a doubt the pads are seated correctly because I had issues with the clip in the past. I even found a thread I started on the clip issue. I am so paranoid about this clip now I used a flashlight to ensure it is in place and the pad is seated in it before I put the retaining screw all the way in.

Sounds like the pads are not bedded yet ( if all other is correct )

I know its referring to cars, but I do my bikes brakes the same way for break-in..... read the below:
http://www.powerstop.com/brake-pad-break-in-procedure/
http://www.tirerack.com/brakes/tech/techpage.jsp?techid=85

I think you're good then, some folks will use a spray... forgot the name of it, on the back of the pad that will keep it from vibrating until it's seated and I think that little white pad thing that comes with the pads - assuming it still does - is supposed to help with that also. When I had my wings I would actually file the edge of the rear-side of the pad to keep them from vibrating, I noticed that on my wings more then the ST.