The route we like to take is Hwy 15 to Barstow and then Hwy 58 to Hwy 101. Avoid I-5 and Hwy 99. A good stop over place is the RV park at the glider airport at Tehachapi. Good town for fuel and food.
Hwy 101 is the most scenic route up to San Francisco and will take you straight into the city. Avoid the San Jose to SF stretch before 10 am and after 2 pm and you will be fine. An alternative route from San Jose is Hwy 280 to SF and you can take the Hwy 1 - 19th Ave. route past Golden Gate Park and to the Golden Gate bridge.
