Northern Arizona, Southern Utah Route ??
 

Is there a paved road, a straight shot, from Colorado City,AZ to Mesquite, NV. without going up 389 to 59 and up to Hurricane? Maps show several roads (dirt?). Are any of them paved and suitable for heavy Road Bike?

Not sure, but Benchmark maps have some of the best maps of the western states IMO. If it shows dirt here, it will be dirt.

I used to live in Pinon, AZ, northeast of Flagstaff, on the Navajo Reservation, and we had quite a few dirt roads--not good for street bikes, though--not good for anything come to think of it! If it shows dirt on a map, you won't want to take it on a heavy street bike, although there are always those who will say otherwise, lol.

Benchmark Folded Maps

I doubt there are any paved roads that go straight to Mesquite, NV. It's only about 80 miles away, so I can't see them bothering to build a road that cuts off 30 or so miles. Roads are pretty sparse in that area.

None! all dirt and the one main dirt route has lots of rock on the Navajo Trail section of it. You'll need to stick to 59 and 9 to the Interstate.
Allen.

Thanks everyone for the info.