I'll be doing a summer internship in SF this summer for about 2 months and wanted to continue biking while I'm there. Should I rent a road bike or try to find a used bike? I won't have a car so I'm thinking about getting a bike anyways to commute around but I'd like to have a nicer bike to go far and tackle some hills. If I should rent, what shops do you recommend?

Also, what are some friendly cycling groups or partner programs for casual riders like me who can only go 15 mph avg for now? New to SF and no data on my phone so would be nice to have another person to ride with.

Feel free to provide any other advice for biking in SF if you think of anything. Thanks!