A few things to add:
Highway 101 is the only coastal option until you reach Leggett. If possible, take Avenue of the Giants some miles north of Leggett which runs parallel to Highway 101. I've rode in flat bed tow truck that managed well enough with our SUV strapped in...you're probably not going to make every corner, so monitor on-coming traffic, pull out when needed, etc. It's worth it if you can "fit." He just drove it like we're playing Grand Theft Auto and figured if a flat bed tow truck is barreling down on YOU, you will move...they did.
From the turn off at Leggett to the coast is one of the best stretches of Highway 1 when it comes to motorcycling. RV'ing...ummmmmm...yah, challenging. I've seen a few firetrucks (30ft) go through there. It's also not well traveled, so again just monitor and manage accordingly. Alternatively you can always link up to Highway 1 through any of the roads that run perpendicular; however, they, too, are curvy. Honestly unless you took 20, I'd avoid the other roads that link Highway 101 to Highway 1.
Once you get to the coast from the Leggett turn off, it's fine. You won't have another issue with exceptionally curvy roads until you reach Big Sur with some minor exceptions. There are only a handful of switchbacks along the way.
(Yes, San Fran. is a mess, and others have addressed what you could do there.)
Big Sur - the section here isn't that long, but there are some windy areas and some curvy areas. With that said, I have seen dozens and dozens of all sorts of RV's through there. The only thing I'll say here - monitor traffic behind you, and use pull outs as needed. Don't be "that guy."
Past Ragged Point, Highway 1 is fine the rest of the way south.
Highway 101 thoughts - While beautiful up North, you lose the beauty soon thereafter. You'll be driving alongside large cities if you take Highway 101 the entire way. If you are just trying to get from Point A to Point B, Highway 101 is fine. If you want to enjoy looking out the window, work out a route that keeps you along Highway 1 the majority of the way.
Anyways, as a "local" I thought I would provide another perspective. #introductorypost : )
