Bikes are allowed on 101 north of Goleta (just north of SB) up until the HWY 1 turn off. I've been looking into a similar route and it looks like you have to go north to Lompoc and then east to solvang, I could be wrong aobut this though. You can also go over San Marcos path on HWY 154, but I don't reccomend doing this because HWY 154 is steep and has heavy traffice going 60mph and in most places extremely small to no shoulder. I have seen an ocassional cyclist on it though.....I guess it depends how good your nerves are.