Mirrors are the most overlooked safety device on a motorbike. Riders accept the position the last owner left them in, glance at them rarely, and then wonder where the bike beside them came from. Two minutes of setup changes how much of the road you actually know about.
The correct setup
Sit on the bike in your normal riding posture — where you sit changes what you see. Aim each mirror so that the edge of your own arm or shoulder takes up no more than a sliver of the view, with the bulk of the mirror covering the lane beside you and the road behind. Many Vietnamese bikes use convex mirrors: they show a wide area but make everything look smaller and farther than it is, so treat the mirror view as “something is there,” and your head check as “exactly where it is.”
Check them constantly, in a rhythm
Mirrors work as a habit, not an accessory: check every few seconds in the city, and always before you change position — every lane shift, every drift around a parked obstacle, every filtering move. Before the head check, the mirror tells you whether the space beside you is occupied; filtering-through-traffic-motorbike-vietnam shows how the two habits combine.
Vibration and damage
A mirror that blurs at speed is useless: check that the stem is tight and the glass is not cracked or missing its reflective backing — common on rental bikes, and exactly the kind of thing the motorbike-safety-checklist-before-riding inspection is for. Do not run with one mirror folded in; asymmetric vision is how bikes sneak up on you.
What mirrors still miss
The quarter behind and beside your shoulders stays blind on any bike. Buses and trucks have blind spots the size of your whole bike — riding-motorbike-blind-spots-vietnam maps them. The rule that survives every road: mirrors first, then a glance over the shoulder before you move. That rhythm, plus the spacing habits in defensive-riding-motorbike-vietnam, is how you stay predictable in traffic that rarely is.