As Socobiker and Brah pointed out, Auburn, Nevada City are phenominal, and 2:10 hr drive if you plan correctly. Auburn is a weekday only for me, as Connector trail is fantastic at mach speed with nobody climbing the other direction, PLUS Mammoth bar stuff. Skyline Napa can be super fun 3.5 hour 3000 ft ride, 40 minutes from Oakland. Rockville is one of my favorites too, GPS that place with your Strava and its 3000ft day. Oat Hill mine Rd is sweet, good chunk. Dans wild Ride out and back with Angwin trails tour in the middle is about 4000 ft day and over 4 hr ride, 1.5 hr drive. I have NOT been to exchequer yet, sounds great! Also, if you want to get your XC on, Browns Ravine from Folsom to Salmon Falls is awesome 2-5hr ride and you can add Cronan Ranch (this ride is best in cool weather before Snow melts in High Sierra, Ive always wanted to do a One Way east bound, and hit it all in 5-6 hours). Browns Ravine best midweek with no hikers/horses.
. But a few cool places to explore. Rockville in Fairfield comes to mind.
