Portland to San Francisco
As I figure out a safe, enjoyable route I will post maps and info. Feel free to add your own ideas and experience as well.
Right now the goal is to find a safe road (s) to Leggett, Ca, which is the beginning of HWY1. According to google maps, by going down main highways it is a 500 mile journey. On side roads and lesser used highways it should be much longer. Anyways, once in Leggett hoping onto the 1 is easy and, from what I've heard, makes for an enjoyable, although hilly in some areas, ride.
Why not try 101? Although they call 101 a "highway", the majority of the drive is 55 or below, especially on the hilly parts. It is a very hilly drive, but a lot of people have done it by bicycle before in order to get up to Arcata, CA. So if it can be done solely by muscle power, then I don't see why it couldn't be done with a little engine power. I think you just have to be a little patient ^_^.