After months of stifling heat, the temperature in northern Vietnam has been a shock to the system. An absence of sunshine and distinctly cooler temperatures have led to a complete change of wardrobe: long sleeves, jeans and trainers have replaced vests, shorts and flip-flops. Despite the change in the weather, some things stay the same. City life in south-east Asia is reliably unreliable and chaotic. Hanoi is a city of six-million people, three million motorbike...