While cyclists have the right to ride in the street, that right is conditional because cyclists usually travel at a speed that is slower than motorized traffic. Vehicle Code Section 21202 says that a cyclist must ride as far to the right as “practicable.” The word “practicable” is used intentionally and is quite important. A cyclist must ride as far to right as he/she can, but only to the point that he/she can do it safely. And riding to the right is also conditional. A cyclist can ride farther to the left in certain situations such as avoiding dangerous or bad road conditions, when passing another cyclist or vehicle moving in the same direction, when turning left, when approaching a right-turn-only lane (and the cyclist is going straight), or if the lane is too narrow to share with a motor vehicle. This last condition is widely unknown among motorists and even many cyclists.
Lately I've done a fair amount of riding on the street with (terrified) newbies and one of the things I stress is that maintaining a consistent position towards the right side of a lane - but outside of the door zone! - is key to safety. No weaving in and out of parked cars, no squeezing so far to the right that you end up in the gutter. You need to be visible, predictable, considerate, and assertive.
I'd like to add that on Saturday's Glendale history ride the motorists our (law-abiding) group encountered were for the most part very considerate in sharing the road and giving us space.