Is bike riding in the city dangerous?? Even if you ride slowly...

it's not. just obey to the traffic regulation and you'll be ok and safe.

Depends which city you're in, here in China the traffic is chaotic and mostly people do what they want, even though there are a set of road rules, they get completely ignored most of the time.Very few people wear helmets on motorcycles and nobody on bikes wears them. So yes, I reckon it's really dangerous here. Plus there's the pollution factor -- your lungs work harder on a bike coz your pedalling, so you're sucking in heaps of extra monoxide, dioxide, lead and other heavy metals --- studies have shown this to be far from good for your health. By the way are you talking bicycle or motorbike -- post not clear on this point.

I think it could be dangerous simply because car drivers often do not see bikes. The other thing is that some bike riders tend to weave in and out of traffic unfortunately which puts them and the car drivers at risk of an accident.

Yeah.. always make sure they've noticed you. Wear clothes that are easy to notice, AND A HELMET.