Is it legal for me to drive a bike in Vietnam?

You need an International Driving Permit (1968 Convention) specifically endorsed for motorcycles. Without it, you are technically driving illegally, which can void your travel insurance in the event of an accident.

What is the biggest danger?

Other vehicles. Specifically, buses and trucks often ignore lane markings. If you see a heavy vehicle, get out of its way immediately.

Should I rent an automatic or semi-automatic?

If you are new to riding, a semi-automatic (like a Honda Wave) is more reliable for hills and provides better engine braking than a fully automatic scooter.

How to Safely Navigate Vietnam's Motorbike Culture

Treat every intersection like a game of frogger and never make sudden, unpredictable movements. Stay predictable, keep your speed low, and always let the larger vehicles—especially buses and trucks—take the right of way.

Master the art of the 'constant' walk. When crossing a street, walk at a slow, consistent pace. Do not run, and do not stop. Motorbike riders calculate your trajectory; if you maintain a steady speed, they will flow around you like water around a stone.
Pick your line at intersections. If you are renting, always stay in the flow of traffic. Never pull out into the middle of an intersection. Watch the locals; if they are inching forward, do the same. If they are waiting, wait.
Check your blind spots incessantly. In Vietnam, 'right of way' does not exist. People will merge from alleys without looking and pass on your right side. Check your side mirrors every 10 seconds.
Use your horn as a warning, not an insult. Honking is a functional tool here. A short tap means 'I am here, don't move into my lane.' It is not aggressive; it is necessary for communication in dense traffic.

Is it legal for me to drive a bike in Vietnam?: You need an International Driving Permit (1968 Convention) specifically endorsed for motorcycles. Without it, you are technically driving illegally, which can void your travel insurance in the event of an accident.
What is the biggest danger?: Other vehicles. Specifically, buses and trucks often ignore lane markings. If you see a heavy vehicle, get out of its way immediately.
Should I rent an automatic or semi-automatic?: If you are new to riding, a semi-automatic (like a Honda Wave) is more reliable for hills and provides better engine braking than a fully automatic scooter.