How to promote better bicyclist behavior

American urban cyclists are often a rude lot. I say this as one myself. Without allowing (valid) excuses like lack of safe bike infrastructure, or responding to aggressive car drivers, us riders are responsible to behave safely around others. I notice this most when people on bikes mix with pedestrians in narrow spaces. In those cases I routinely challenge other riders to dismount. They don’t often respond well, even when I frame it as helping give all bicyclists a better reputation. If you were trying to get a peer from the same group to behave better, how would you apply positive peer pressure?