Thanks for invite. I'll be on a cruise in late May. Next time. Keep in touch when you head this way.
Five ways to get to AZ Strip from Mesquite:
1) Gold Butte Road via Whitney Pockets and Whitney Pass.
2) Lime Kiln Canyon - direct from Mesquite.
3) Elbow Canyon - steep and loose.
4) Black Rock Road Exit (1-15), Gypsum Mine, Maple Canyon -- this is your photo
5) River Road and south on BLM #1069 or County Highway 5. This is the main route south from St. George to Mt. Trumbull Schoolhouse.
If coming from So Cal and staying in Mesquite, I would opt for Gold Butte or Lime Kiln.
Both are scenic and completely doable on loaded bikes. Elbow Canyon is tough as you know.
Choice 4) Maple Canyon is nice, but the problem is you have to ride I-15 up through the Gorge. Not bad as interstate goes, but certainly not dirt. Same for choice 5). Ride I-15 to new Airport Road exit on south edge of St. George. Both 4) and 5) require about 30 miles of I-15 through the Virgin River Gorge. You can avoid some of it by using frontage roads and a bit of dirt, but there is no work-around for the section of I-15 from Cedar Pockets north to the Black Rock Road exit. About 10 miles of I-15 that can't be avoided.
Check out Post #279 on Page 19 for good detail and maps of Choice 4) Maple Canyon.
Post #391 on top of Page 27 shows Lime Kiln Canyon and Rt. #101 past Mud Mountain. Map also shows dirt on north side of I-15 to Cedar Pockets.
I rode #101 from Wolf Hole over Whitney Pass and exited via Whitney Pocket onto Gold Butte Road earlier today. I'll post up pics shortly.
If you haven't done Whitney Pockets / Whitney Pass (this is Gold Butte Road), I'd opt for this route. Road is in good repair the entire way. Some sandy patches near Mud Mountain. Plan on taking some time, perhaps 4-5 hours from Gold Butte to Wolf Hole via Whitney Pass and #101.