On the left side the rotor mounts so it protrudes outside roughly 1/8" from the hub. On the right side the rotor mounts so it's recessed about 1/8" in from the outermost part of the hub. The wheels are directional and this makes it obvious.
Just wondering why they're designed this way?
I never noticed until I mounted the right side and saw there was some exposed hub. Like the groove the rotor sits on is deeper than necessary. I made sure the powdercoater didn't coat this area but didn't realize there would be some stock fimish showing after mounting the rotor. I just applied some paint to blend it in.
I don't know if it has something to do with anti-lock braking or something my US '07 doesn't have? Some models rear wheel have a sensor plate that mine doesn't. Maybe this wheel is used on other bikes?

Some models rear wheel have a sensor plate that mine doesn't. Maybe this wheel is used on other bikes?

I think you answered your own question. Same wheel for both non-ABS and add that tone wheel pickup for that difference in clearance and there you go... No tone wheel is that gap you see on the right side.

You did use new or reused the paper gaskets that came in between the disc and wheel hub, right?

Yes, I re-used the paper plates. The difference is much more than their thickness too.
In the factory manual I noticed the rear wheel having the optional sensor plate but didn't see anything about the front. Didn't really look at the front regarding anti-lock braking. Does the front also have it optional on some models?

Front wheel ABS is all about stopping, so yes, fronts especially. The front wheel has a few directional arrows located on the left side wheel webbing you sitting on the bike for proper directional reading. Look in the triangles of the disc. stand in front of the bike and look down in each large and small triangle shaped disc cutout. Look for the DOT castings. The arrows will be on the left side of the cast spokes you have the wheel placed in it's correct travel direction.

Another faster way is to see the snout on the left axle bearing seal housing has the taper on the left. Look on the right bearing housing axle side, you see the square shoulder for the ABS tone wheel to sit center on. Now we are talking a measurement of taking a quarter and lay George's head on the boss. We should still feel the edge of the bearing housing with the quarter in place.

If that quarter cannot be placed there; is on the edge and is about to fall off? You have the paper over the powder coating are you saying? Then that brake piston sits that much closer in the caliper, the piston on the other side moves equally farther out as the brake pads wear. Might not be that big a deal if that is what you mean. However, if you feel the disc off the edge where the quarter should be? No, I would not ride the bike till that disc is moved back in farther.

Did they coat where the paper gasket goes? That is machined flat so the disc rides square. The gasket tones the harmonics down or you'll squeal like a pig like wet finger over and around a wine glass rim hold your ears.

No PC on the area where the rotors mount. Made sure of that.