I'm going to be flying into SEA in the next two weeks and will be in the area for about three months.

Can someone please confirm my understanding of the current situation in regards to buying a motorbike and traveling through different countries?

I'll be on a tourist visa.

Vietnam:

- You have to have a Vietnamese driver's license, so I could take the written and riding test: https://www.youtube.com/watch?v=UzHgdMNa-Fk
Apparently a lifetime driver's license can be had for $145 USD.

- I can buy the bike like a Honda Wave or XR 150, but because I'm a tourist there is no chance I'll be able to get my name on the Blue Card, so technically I can't prove ownership?

- From Vietnam, with a blue card not under my name, I can ride through Vietnam, Laos, and Cambodia, but have no chance going into Thailand, because the blue card is not under my name.

Loas and Cambodia:

- not recommended to buy bikes in these countries?
-

Thailand:

- To buy a bike, need to have proof of residency and address which requires a renter's agreement and then a visit a Thai Immigration Office. Has anyone found their hotel or hostel willing to provide this?

- Need to have a 90-day visa

- Getting the plates to cross into other countries takes about a month

Malaysia:

- I need a proof of residency to buy a motorbike
- I can cross into Thailand, but maybe not into Cambodia or Laos?

Summary:

Basically it seems like Thailand is the big wedge stuck in the middle of SEA that prevents easy overland passage throughout SEA.

So is it best to, say, fly into Hanoi, buy a motorbike, ride south through Laos and Cambodia, park the bike in Cambodia, go into Thailand by bus, rent a Thai motorbike for the duration of the Thai trip, then return to your bike in Cambodia and head to HCMC, and then back north along the coast to Hanoi?

And just forget about Malaysia and Myanmar?

So basically something like this:

https://imgur.com/a/iuD5aRf

Im not very well known about purchasing bikes in Vietnam but for the rest you seem to be mostly correct. But remember this is SEAsia and enforcing and interpretation of laws and rules changes as often as a normal person changes underwear.
The 90 day visa you talk about for Thailand - thats a Non Immigrant visa and I really dont think you will need that type of visa. A normal tourist visa of 60 days should do. I have even heard of several who bought motorbikes on a visa excemption 30 day stay. But again - this is about interpretation and enforcement of laws and rules. The time one have to wait for documents and new plates in Thailand can vary a lot from province to province, from a couple of weeks to several months.

Entering Laos have become more difficult the last years. From the thai side most borders demand that you are in a group and het permits, and mostly they seem to enforce the old rule that says you need at least a 250 cc bike to be able to enter Laos. Then again not all borders seem to enforce this rule.

Basically renting is so much easier in all of these countries that it must be the better option. No document requirements, no visa requirements, no insurance requirements, no bordercrossing hassles - just rent and go! Its actually a no brainer if you ask me...

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