In my commutes I often see cyclists ride quite fast between car lanes (for example when stopped at traffic lights, they get to the front to the lights before it gets green so they don't have to wait till all the cars start moving).
When there is 1m-1.5m, it is quite easy, but how does one master the width of the bike? Every time, I am on the brakes feeling I am that close to the cars' mirrors but on the same time I see cyclists ride by without even slowing down, even motorbikes...
If even motorbikes get in that space, I must be doing something wrong, so how does one get conscious of the actual width of the bike?