Thoughts for Northern California:
Cambria is a great place to stay. Look to visit Nitt Witt Ridge and maybe stay at this B&B, Victoria's Last Resort.
From Cambria, come up the PCH and stay in Carmel or Monterey for the evening. It's less that 100 miles from Cambria to Monterey but you will most likely want to take all day as the views a breathtaking, lots of photo stops, and look for the waterfall at Julia Pfeiffer State Park, just south of Big Sur. Lunch at the Big Sur River Inn, sit out back in the big Adirondack chairs and dip your feet in the running stream out back. They also have a hotel there too - pricey but very nice.
In the Bay Area, there are a tone of fun roads in the mountains - 9, 35, 84, Alice's, Stage Rd., Pescadero Rd., and tons more!
Immediately north of SF, just as soon as you cross the Golden Gate Bridge, take 2nd exit which comes up very quickly, just past the vista point. Turn left and cross under the roadway, then go up the hill on Conzelman Road. Very shortly you will see a number of turnouts on your left which give you great photo ops.
NOTE: Conzelman Rd. is closed for construction. You can still take the same exit but go RT at the offramp down the hill toward Sausalito and turn right onto East Rd. for a different view of the bridge. There is also the south side of the bridge at Fort Point (do a search here as several have photos of both vantage points - also check WheatonFJR's thread on his and Airboss' trip out this way last May).
From there you can backtrack to Highway 101, or you can fart around the area called the Marin Headlands. Nice riding, a lighthouse, old battery, beaches, a marine mammal rescue place.
You can still get out to the Headlands but you'll have to take the tunnel off of Alexander Ave (the exit already mentioned) directly out to the beach... it is really beautiful out there.
Decision time: Muir Woods or not? Muir woods is a redwood forest national park kinda place. Busy, but magical if you haven't been in a redwood grove. Follow your maps/gps to get there. I personally would skip the woods and enjoy the totally awesome twisty and ocean-view highway.
Also, consider riding to the top of Mt. Tamalpais - great road and awesome view (as long as it's not foggy!).
Next place of note is Point Reyes Station. There's a cafe, a bakery, a market, and if you time it right, motorcyclists to visit with. Also the option to visit Pt. Reyes National Seashore. Miles of secluded roads, forests, a gigantic empty beach, and a lighthouse. Fun place to visit, but it will impede your forward motion as the only way back out is through Pt. Reyes Station.
My personal 2cents is to forego the lighthouse. It's a crapshoot if you will even be able to see the lighthouse because of the fog and the road out is fraught with high winds, rough road, and cow pies all over the place... very treacherous.
Bodega Bay has a good restaurant right on the water. I can't remember the name of it but you can't miss it. Recommended.
The Bodega Coast Inn is where we stayed for the Rolling Illinois Cluster Feck in May. Very nice place, ocean view rooms, etc.
Next motorcycle spot of note is the store at Stewarts Point. There is a road coming in from the right called Skaggs Springs Road. This is a well known local motorcycle road - loads of fun. It will take you all the way to Hwy 101, though, so don't take it unless that's where you want to go. You can just pay homage as you pass.
Or you can take Stewarts Point/Skaggs Spring inland, and then hit 128 out of Cloverdale back out to the coast.
On a normal person pace, you're probably ready to sleep by the time you get to Mendocino. It's a cool hippie/yuppie/new age town, but mucho spendy. If you are on a budget you can head just a bit further north and sleep in Fort Bragg.
As you go further north, you may be interested in exploring the Lost Coast. The roads are lonely and bumpy, but the reward is that you'll get to ride where few ever do, and see the westernmost spot in California. Look for Mattole Road, Honeydew, Petrolia, and Ferndale.
And don't forget Avenue of the Giants! Once up in Fortuna, must do roads include 299, 36, 3, and 96.
And that's the Norcal coast according to me. Have fun! Let me know when you're in SF, maybe we can get together and I'll sign your Iron Butt witness forms!