Originally Posted by sacrider
While there are great roads all over the US and California in particular (yeah, my local bias!), following are some you should do your best to ride if you have the time
Agree with all of that! My first thought on looking at the google map was "wow, that's a lot of superslab."
From Vegas to LA it's going to be hot no matter where you go, so you might as well go through Death Valley or Mojave, it'll be a lot prettier than the freeway, and the routes into LA from the North are nicer.
+1 on taking the coast up to SF, and tooling around the Santa Cruz mountains on the SF peninsula.
+1 on Skaggs. Don't take 80 from Sacramento to Santa Rosa either, 128 will be a lot more fun, and there's a little tiny road from St. Helena to Santa Rosa that's very pretty.
101 at the very top of CA and in Southern OR isn't really anything special either. Might consider 299/96 or 199 over to Medford OR, then head up to Crater Lake before cutting back to the coast. Beautiful stuff up there, and you might even see bigfoot.
I've done that same route from Chicago to Flagstaff before. It'll eat up the miles, but that's about it. I don't know enough about the area to say whether any of the backroads are worthwhile.
Be prepared to wait in the heat in traffic crossing the Hoover dam on your way to Vegas. There's really no place to stop there either -- take water, it could be an hour or two of stop and go depending on the day of the week, and lane sharing isn't legal until you get to California.