Carrying lots of stuff on bicycles

[Michele]

It would be worth trying to rebuild in GURPS mechanics a bicycle with the old GURPS Vehicles. Two wheels, musclepower propulsion, light open frame - you could end up knowing the theoretical maximum payload.

For using a bike as a two-wheeled cart, you can simply use the rule on p. B353. On a good road, you'd divide effective weight by 20! (by 10 for a two-wheeled cart, and halved for the road). The upper limit would probably kick in, which is 15 x BL.

[Bruno]

The big reason why you see enormous loads balanced on a bike instead of in a bike trailer is heavy traffic: A bike trailer makes your bike that much bigger and harder to maneuver in a press of people.

In an ATE situation, you shouldn't have that kind of population density, making a trailer (or sidecar, or what-have you) much more viable. That said, given a trailer, some people will overload the trailer, and then overload the bike.

[ericthered]

Originally Posted by Bruno

The big reason why you see enormous loads balanced on a bike instead of in a bike trailer is heavy traffic: A bike trailer makes your bike that much bigger and harder to maneuver in a press of people.

In an ATE situation, you shouldn't have that kind of population density, making a trailer (or sidecar, or what-have you) much more viable. That said, given a trailer, some people will overload the trailer, and then overload the bike.

Actually, I can see a bicycles remodeled or cannibalized a lot. Bicycle wheels are just the right size and weight for a lot of applications, but you often want a larger vehicle than a bike.

[khorboth]

Originally Posted by ericthered

Actually, I can see a bicycles remodeled or cannibalized a lot. Bicycle wheels are just the right size and weight for a lot of applications, but you often want a larger vehicle than a bike.

When I was young, bicycle trailers were much less available, so my father made his own. It held a small amount of cargo and two carseats for my sister and I. After several failed attempts using bicycle wheels, he wound up using wheelchair wheels. They are approximately the same size and much more durable.

[tshiggins]

During the Vietnam War, Mr. Victor Charles (Sir!) received a large percentage of his supplies via bicycles along the dirt tracks of the Ho Chih Minh Trail across the Annamese Cordillera.

Those were older bicycles with heavy frames, further reinforced as needed. Additionally, the seats were replaced with vertical hand-holds, welded to the frames.

That means they weren't ridden, they were pushed. A single operator pushing a cargo bike averaged 6 miles a day across alpine trails with loads of up to 440 lbs. (200 kg).

I think that's probably a practical upper limit in cargo mass for a regular bicycle, although a modern cargo bicycle could probably go a bit higher. Also, even a broken modern highway would allow for faster travel than the Ho Chih Minh Trail.

That said, there are practical upper limits to human strength and stamina. I have a difficult time imagining anybody making more than 10 miles a day with 450-475 lbs, though.

[Icelander]

Originally Posted by tshiggins

During the Vietnam War, Mr. Victor Charles (Sir!) received a large percentage of his supplies via bicycles along the dirt tracKs of the Ho Chih Minh Trail across the Annamese Cordillera.

Those were older bicycles with heavy frames, further reinforced as needed. Additionally, the seats were replaced with vertical hand-holds, welded to the frames.

That means they weren't ridden, they were pushed. A single operator pushing a cargo bike averaged 6 miles a day across alpine trails with loads of up to 440 lbs. (200 kg).

I think that's probably a practical upper limit in cargo mass for a regular bicycle, although a modern cargo bicycle could probably go a bit higher. Also, even a broken modern highway would allow for faster travel than the Ho Chih Minh Trail.

That said, there are practical upper limits to human strength and stamina. I have a difficult time imagining anybody making more than 10 miles a day with 450-475 lbs, though.

That's pretty cool.

If you were using bicycles in this way in an AtE/AH/'Lest Darkness Fall' type scenario, but the terrain was Westphalia, without any modern roads, how might the bikes evolve over the years?

There won't be any brick or stone roads, but the pre-Roman tracks might have been somewhat better than goat tracks, if only because there was regular traffic, which would tend to lead to something resembling a dirt road. The best of such tracks would be the Hellweg, at that time not a proper road as it would become later, but still a route that was fairly level and avoided mountains or thick forests, and was used for salt trading very early in European pre-history (maybe from -3,000 BCE), and where carts full of salt may have driven even before any permanent road-building was done.

What kind of modification could be done with TL2 to TL4 infrastructure (but TL6 to TL7 know-how) to make thousands of 1930s and 1940s vintage bicycles into more effective off-road transport and cargo vehicles?

What do you use to replace rubber tires, when they give out?

[Anthony]

Originally Posted by tshiggins

I think that's probably a practical upper limit in cargo mass for a regular bicycle, although a modern cargo bicycle could probably go a bit higher. Also, even a broken modern highway would allow for faster travel than the Ho Chih Minh Trail.

The big limit is slopes and stretches that are impassible by bicycles. Good wheels on flat ground are about 5x as efficient as walking (B353 dividing effective weight by 10 or 20 is wrong, it's just that you can also move a load super slowly).

[Lord Azagthoth]

During the Vietnam War, Mr. Victor Charles (Sir!) received a large percentage of his supplies via bicycles along the dirt tracKs of the Ho Chih Minh Trail across the Annamese Cordillera.

During WW2, the British soldiers in SE-Asia were surprised how much equipment and provisions the Japanese soldiers took with them. The Japanese uses bicycles but they did not ride them (or they had to retreat very quickly, had good terrain or needed to encircle the enemy), just used them to carry their equipment and provisions. They took 36kg with them (versus the 18kg the British carried).

[SionEwig]

Just to throw this out there, but when I start conditioning for a bike tour I'll load 160 lbs. on my bike (70 front/80 back/10 mid) and have no problems. As to what skill to use, I'd go with either Freight Handling or Bicycling, which ever is higher.

[tshiggins]

Okay, as for the bicycles, themselves, I think they'd switch to wooden tires with iron strips, once the rubber gave out. That makes the bicycle heavier, and the ride more rough, but the spoked metal wheels make for much more efficient motion than wheels for wooden carts.

As for the bikes, themselves, I'd think designs would start to resemble the cargo bikes of today, because similar desired outcomes will be met in similar ways, given a common original technology.

https://www.bicycling.com/bikes-gear...t-cargo-bikes/

As for the roads, I'd think the ASNs would address some of the problems caused by lack of rubber with improvements to the roads. After all, what you need is a way to keep the wheels out of the mud in the low country, and gentle slopes in the highlands.

The work would be labor-intensive, but working slaves to death would be in keeping with the themes. It would be easy enough to start with wooden bike trails, especially if they have to clear forests, anyway.

https://www.cliftonpark.com/parks/trails/
https://www.spinlister.com/blog/moun...on-bike-trail/

They'd have to pick the right routes to keep the grades gentle, but raised wooden trails address the mud problem, nicely, and utilize available resources.

After that, maybe shift to plank roads, at least for a while. Those sucked for heavy truck traffic, but are a better choice for cargo bikes and animal carts. Even the small horses can do useful work if properly collared, or have breast harnesses and swingletrees.

https://en.wikipedia.org/wiki/Plank_road

After that, once they've captured enough slaves and located the proper materials, they construct Roman roads.

https://en.wikipedia.org/wiki/Roman_roads

That puts them in pretty good shape, and makes for a logical progression, given their knowledge and circumstances.