I've seen posts in the past about various loose nuts and bolts that are common on the ZR-7(S) that account for various rattles and buzzes on our bikes.
Last night, I did a quick check of my bike looking for them. I found:
-4 of 8 exhaust nuts were loose with 1 barely more than hand tight.
-2 of 4 of the 6mm axel bolts were a little loose
-3 of 4 of the 4mm fairing bolts were loose in varying degrees
The bike wasn't what I would consider to be noisy before checking, but was noticably quieter riding into work this morning. When you have a few minutes, you might want to go over your bike. I admit that what I found suprised me and I'm going to make a note to add this to my periodic maintenance check list.