I have ridden the
ACA Western Express Trail from San Francisco past Folsom to Carson City (and back).
I took the ferry from San Francisco to Vallejo and started riding from there. I had friends in Davis, where I stopped for the night.
There is a bike lane from Davis to Sacramento that is right next to the freeway. From Sacramento, you can take the American River trail (as mentioned above) that takes you to Folsom. Note that the trail has thorn bushes all along it and flat tires are common, so take a patch kit and/or extra tube.
I wrote a journal of that ride. Here is a link to the journal's
first day from SF to Davis.