Wow really? You spent 4 weeks in London and never saw a cyclist? Were you out in the suburbs? I spent a bunch of time in London and saw a TON of cyclists in central London. Many of them took the train out to where I was staying too (outside Brixton).

I also don't buy the "small apartments" thing. We live in a 650sq ft apartment and have 4 bikes hung up on our wall. Where there's a will, there's a way.

Not surprisingly, being London, the weather was lousy.

650 sq ft is a pretty large place by Korean standards. I expect by Tokyo or Singapore as well.

It was grey and lousy when I was there too :-) Still a lot of cyclists including my old coworkers.

I'd dare say we could fit 4 bikes in a much smaller place too. It's not the size of the place that's at debate here though.

It was so strange that I even remember one of the few riders I saw because he was using the DLR to get near the tower. I was curious if you could bring bikes on it and that answered my question.

Electric cars are a very uncommon mode of transportation too. Should we therefor not care about promoting that method of transportation? No, because then the status quo would never change.

The article discussed in this thread brings up one suggestion for overcoming practical issues. There are many, many more (proven) solutions to choose from -- when you make bicycle transportation pleasant enough, people will start using it.

If the "social issues" you talk about are because there's a group of people who thinks transportation by bicycle is uncivilized, I think it is a matter of education and tolerance. Once using bikes is common in a country, you will see that the only social issues are about people having unjustified fears (about the implications of considering bicycles as a method of transportation during city planning) and there are no real social issues other than people being dicks.

I don't have to rebuild every major piece of transport infrastructure to support electric cars.

Social issues refer to body odor my bike riding colleagues carry around with them all day because our workplace doesn't have a shower.

We tear up and rebuild roads all the time. As we do, it's not that big of a deal to give more consideration to other modes of transit.

Buildings don't move themselves.

There's plenty of width in most roads, save for some narrow places you find in the older cities in the Northeast and Atlantic coasts.

In Osaka / Tokyo / other large Japanese cities people ride bikes on the footpath instead of the road. They also ride comparatively slowly and the terrain is largely flat so in the cooler months sweating is a non-issue. Additionally folding bicycles are very popular because, as you say, the apartments are often very small. Finally, because the cities are so compact you rarely have to travel a large distance to get to where you're going.

So all and all, I agree with you, it's common in these places because the combination of these things makes riding very practical and they're noteworthy because of it.

-edit- I forgot to mention that most apartment buildings will have stacked locking bike racks. This combined with the generally low rate of theft, easily available recycled (read: cheap) bicycles makes them very affordable and low risk.