Just had a case of the rattles recently. In fact , it came back after 3 years of me thinking it was fixed. coming form the front end/fairing area, only noticable in high rev range at low speeds, between 4 and 7 thou rpm.
Underneath the front black part of the fairing at the bottom (nose area) is a male plastic end that goes to a female grommet. My rubber grommet (meant to be inside) was missing when i got the bike new, fixed it with black foam tape around the (male part), the tape had shifted and was now allowing plastic to rattle against plastic. Picked up a toyota rubber grommet from the window handle section from crappy tire ($3) popped it in, fixed...check this area on your bike, you'll have to remove the mirrors as if you were about to remove the windscreen.