Some pictures of hard working mopeds in Vietnam.
All sorts of mopeds are used like this, but these are all Babetta model 210s.  There is some information about these bikes at the bottom of the page, from a Vietnam resident.

The following is an edited version of some correspondence that I have had with Karl Gorczynski who currently lives in Vietnam, giving an interesting view of the position of Babettas in the country.

I'm an American who's been in Vietnam for 3 years. I've bought a Peugeot and a Vespa from the 60's and have been eyeing the Babettas that are on the bottom of the respect totem pole here.
I was planning on buying a cyclo to drive my wife and 2-year old around in.  Yesterday, when in another city, I saw two transport vehicles that were cyclo in the front, matched with a Babetta (meaning a Babetta minus the front wheel). I want one!
Cyclos are three wheeled mopeds or, more usually, bicycles with two wheels at the front with a seat between, for carrying goods or people, usually tourists.  Cyclos, known elsewhere as the cycle rickshaw, have long been a popular form of public transportation in Vietnam as it  is safe and inexpensive.  In Vietnam, it has also been indispensable for carrying all kinds of goods, especially in and out of narrow alleys where bigger vehicles cannot enter. The capital city, Hanoi, is about to ban their use claiming cyclos are no longer suitable for the city's crowded streets, as they can cause congestion or slow down the flow of daily traffic.
The cyclos have remained unchanged.  In Hanoi maybe half have been made pretty and padded and they are owned by companies who get hired to take tourists sightseeing around the center of the city.  Itís a thousand times safer than walking because drivers are both lawless and insane. The other half here - and most throughout Vietnam - are looking rough and are used to carry kids to school, pregnant women (itís better than a bicycle or motorbike, and cheaper than a car taxi) and all manner of things, furniture, iron bar, etc.  Cyclo drivers are way down on the social / economic ladder.
For some reason, problems with the police most likely, not one motorized cyclo plies the streets of Hanoi. The two I found are 60 miles away, and places that far away from a big city are 50 years behind in many ways.
In Hanoi there were a ton of Babettas. Now there are quite a few but they're used for the most dirty and menial of transport duties.  Metal stuff, mostly. You'll find them parked in front of small, welding shops on the dirtiest of streets. A metal junk yard here is getting a lot of them and they melt them down. When the police snag one for law violation, it gets abandoned to the police. They're worth less than US$10 at that point.
I've been trying to get my Vietnamese wife to get the better ones from the scrap guy and police (she's talked to both) and it is possible but itís quite a hassle, time-wise (as it everything here) and she can't feel that its worth even 10 minutes of her time to do so.  We've now moved to an apartment where I have room to tinker and I am pushing her starting today.
Dealing with the locals is more difficult for foreigners so my wife does all business dealings because itís universally thought that itís only right that foreigners should pay more.  But itís very tiring for her also to try not to be cheated.  Be that as it may, I'm not Vietnamese, and here I have to be very on my guard in any dealings with  the locals.
Mostly I hate to see old things abandoned or destroyed just because they're out of fashion.  Old Vespas are now getting interesting to 'hipsters' here in the north of Vietnam, getting shipped-up from the south, while the general population still scorns them. Mobilettes and Peugeots are still uninteresting to people. Babettas are totally ignored.  A young man with a Babetta could never  have a girlfriend in the city. No way!  Old things don't give a person 'face'.
I'll start acquiring Babettas when I learn what parts I should try to get. I hope to buy the Babetta cyclo that I saw, next weekend. We live on the outskirts of Hanoi and I expect no trouble from the local cops with it.
Karl Gorczynski,   Hanoi, Vietnam.