The UCSD Bike Shop is a full service bike shop with reasonable prices. It also has valuable information on biking in San Diego. The UCSD bike shop is located in the old Student Center. Use tools for free (on the premises) with your student ID. The mechanics are competent and willing to explain how to do your own repairs. In purchasing situations where a variety of options are available, they are willing to explain all options at length. Prices are generally comparable with community bike shops; although certain things are much cheaper: helmets go for $25 at the bike shop, $50+ at University City Cyclery. The convenience and tool use policy are a plus. You can also get a discount here with Pedal Club.