Do you still have the original E3 tires that came on the bike? Mine rear tire was making a similar noise at about the same speed, particularly when in a lean doing 55 mph. I only had a few thousand miles when they started making that noise and the noise just got worse till I replaced them at 10k miles.
2011 Cross Roads Sunset Red
OEM short windshield, passenger backrest, crash bars, saddle bag bars, heated grips, vinyl closeouts, tachometer, ambient temp, LED headlight, luggage rack. WD lay down licence plate.