Easily the biggest problem in the US with biking is that the infrastructure is, nearly without exception, absolutely atrocious. Nobody would accept having only 'painted walk lanes' on busy streets to get around, much less having them appear and disappear from the road seemingly at random, and yet that's the default state of bike lanes in nearly all US cities. If biking had as much infrastructure as even walking -- me…
Bike lanes are a step in that direction. SF is starting to gain more protected bike lanes, it would definitely be nice to have more. The bike lane itself is a great initial way to measure bike interest. Though honestly, nearly every street in the city should have at least a painted bike lane.
There are also streets where biking isn't allowed. These are mostly major car arteries. It is imperative to realize there are places where cyclists don't belong. Just like it is imperative to realize that in most places in the city, cyclists do belong.