East Rim Drive of Grand Canyon South Rim. From North 89 at Cameron, runs West to the park, then along the rim for 25 miles. My favorite view is from Navajo Point. Unless you wanna hike, you can leave your bike unlocked, most of the points are just a few parking places along the rim. Just East of Grandview Point is a Forest road running South. If you can make it 400 yards you're legal to camp. The climb from Cameron up out of the Painted Desert is great.
South Rim Village sucks, I think, no where to park a Moto safely. From the Village, you can run South to Williams, or down 180 to Flagstaff. 180 is pretty, with a few nice corners. If you are looping North from Flagstaff to get to the Canyon, go through Sunset Crater and Wupatki National Monuments. Best pavement we have around here, nice views, and really interesting Native ruins.
Both of these in a day might be rushed. About 180 miles round trip from Flag just to do the South Rim (worked up there, never want to do that commute again).
Enjoy, and don't shop and Flag Motorsports unless you are totally without other options.....
ATGATT: When you fall off your motorcycle, you will be wearing what you were when you got on your motorcycle. Dress accordingly.