I ride the lower part often... Hwy 93 through Brown Crossing... Have not been all the way to Interstate 40.
There are some rough spots North of Alamo Lake, may be difficult for big-bikes.
Some guys from Tucson were wanting to know about Brown Crossing a few weeks ago. I sent some pix.
Perhaps you can search my old threads for pix's.
Send a report if you make the trip...
Mark, a Misplaced Farm Boy....