I've done medium length trips (= within Europe) on a 50cc bike (Honda C50) and on a number of 100 -125cc bikes. The larger bikes were ok - even on the autobahns, although having huge trucks a few inches off your back wheel for miles on end can be a bit intimidating.

Once, on a 100cc Suzuki, I got boxed in by 4 trucks - front, back, left and right on the autobahn near Frankfurt. It was dark and wet and I'm not sure three of the truckers knew I was there. The (two stroke) bike was flat out for about 2 miles before the formation broke up.

The C50 was just too slow - more akin to cycling (that's on my bone shaker bike, not Tour de France stuff). Even with the right "mind set" it was too slow. Speed I'd accept as ok on a pedal bike (at least I'd be getting fit!) was just frustrating on the Honda.

I suppose it might have been different if I'd had an open ended schedule and could live with just covering a few miles each day but I didn't. The second time I used it in Europe I left it in Germany and got a pillion ride back on another bike.

That's what I'm afraid of, to be honest. It might be different outside of Europe though but then again it might not be powerful enough for going offroad - one might get stuck somewhere.

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"Life is not a journey to the grave with the intention of arriving safely in one pretty and well preserved piece, but to skid across the line broadside, thoroughly used up, worn out, leaking oil, shouting GERONIMO!"

Certainly two up the C50 ground to a halt when my wife and I tried off-roading one in Crete (and no, we're not hugely overweight!).

At least it was light enough to push fairly easily but if you have to do that you might as well walk.

Pic taken just before we got to the off road section:

We get ocasional travel reports on Italian Vespa forums, of people doing long journeys on 50cc Vespas, it must certainly be nice to be able to admire the scenery at just slightly more than bicycle speed.

A blog which I found particularly inspiring is this one:

African Moped Ouagadougou - Paris en mob!

I must say I like the idea of being easily able to hitch rides with your bike when the going gets tough, or just plain boring.

I've just bought a second 50cc scooter (2003 Peugeot Elyseo 50 for 300 bucks off eBay) for my wife so we can actually start with taking shorter trips first and see how she likes it.

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"Life is not a journey to the grave with the intention of arriving safely in one pretty and well preserved piece, but to skid across the line broadside, thoroughly used up, worn out, leaking oil, shouting GERONIMO!"

This is a great way to introduce her to bikes and travel. Maybe it will click and she'll get hooked?

If I was inclined to travel on 50cc bikes I think I'd never bother shipping them anywhere. Just buy them locally where you end up, sell off when you move on, or leave there for a return trip or rent to a friend or whatever.

I'm thinking most of Asia this would be possible and also parts of Latin America? Lots of Chinese 50's both two and four stroke sold now in many places in the world for pretty cheap prices. I prefer four stroke for the torque and better fuel economy but two strokes have more HP per CC.

I owned several 50's when I was a kid. I had two Honda 50 four strokes, and later in college a 50cc Honda step through. Also had a 90cc Honda and a bunch of other stuff.

These Hondas were completely bullet proof. I rode them all over Los Angeles, even carrying my Surfboard in one arm and riding with the other. No helmets then. Could not go on Freeway (250cc or more) but top speed was about 50 mph. Not bad and I rarely got in other drivers way except on faster two lane highways. (Stay over to the side! and watch your mirrors.)

We also rode them in dirt and this was my introduction to dirt riding. I raced in later years on bigger bikes but the little Hondas were the real inspiration. Those little bikes would go about anywhere and would NOT DIE.

We even took our 50's to Baja on Surf Trips and used them to explore to find new Surf spots. Baja was deserted in those years. (this in about 1964) We rode our 50's on the beach, through salt water (DEEP!) and they just kept on going. Only problem was flats from the stickers and thorns of the Desert. Lots of flats.

Later we mounted Knobbies and that helped with sand and flats. Like all kids we all wanted more power and a bigger bike. Now, looking back, I realize just how adequate the 50's really were. If you're patient I think you could go anywhere.

Back in the 70's I rode 50cc Hondas all over the place. Top speed was about 45 but they were road worthy then. Today, the highway speeds are much faster. But if I were to stick to little back roads, I think it might be quite enjoyable.