They ride pretty slow, and don't lavishly maintain their bikes in general. You see people smoking while riding a bike in the city. This applies to the typical bike on the street. I understand there is a road bike culture in China now but that's a whole other thing.

I didn't get much chance to talk to people on the street in China since I only know a few words of Mandarin. Most of the software developers I was interacting with had better means of getting around. But I did walk past some working class housing, which is where you see these really large bike sheds. I suppose it's a hassle to carry oil and a tire pump down from one's apartment and back up.