h/t alyssavance

The bicycle, as we know it today, was not invented until the late 1800s. Yet it was a simple mechanical invention. It would seem to require no brilliant inventive insight, and certainly no scientific background.
Why, then, wasn’t it invented much earlier?
I asked this question on Twitter, and read some discussion on Quora. People proposed many hypotheses, including:
+ Technology factors. Metalworking improved a lot in the 1800s: we got improved iron refining and eventually cheap steel, better processes for shaping metal, and ability to make parts like hollow tubes. Wheel technology improved: wire-spoke (aka tension-spoked) wheels replaced heavier designs; vulcanized rubber (1839) was needed for tires; inflatable tires weren’t invented until 1887. Chains, gears, and ball bearings are all crucial parts that require advanced manufacturing techniques for precision and cost.
+ Design iteration. Early bicycles were inconvenient and dangerous. The first version didn’t even have pedals. Some versions didn’t have steering, and could only be turned by leaning. (!) The famous “penny-farthing” design, with its huge front wheel, made it impossible to balance with your feet, was prone to tipping forward on a hard stop, and generally left the rider high in the air, all of which increased risk of injury. It took decades of iteration to get to a successful bicycle model.
+ Quality of roads. Roads in the 1800s and earlier were terrible by modern standards. Roads were often dirt, rutted from the passage of many carts, turning muddy in the rain. Macadam paving, which gave smooth surfaces to roads, wasn’t invented until about 1820. City roads at the time were paved with cobblestones, which were good for horses but too bumpy for bicycles. (The unevenness was apparently a feature, assisting in the runoff of sewage—leading one Quora answer to claim that the construction of city sewers was what opened the door to bicycles.)
+ Competition from horses. Horses were a common and accepted mode of transportation at the time. They could deal with all kinds of roads. They could carry heavy loads. Who then needs a bicycle? In this connection, it has been claimed that the bicycle was invented in response to food shortages due to the “Year without a Summer”, an 1816 weather event caused by the volcanic explosion of Mt. Tambora the year earlier, which darkened skies and lowered temperatures in many parts of the world. The agricultural crisis caused horses as well as people to starve, which led to some horses being slaughtered for food, and made the remaining ones more expensive to feed. This could have motivated the search for alternatives.
+ General economic growth. Multiple commenters pointed out the need for a middle class to provide demand for such an invention. If all you have are a lot of poor peasants and a few aristocrats (who, by the way, have horses, carriages, and drivers), there isn’t much of a market for bicycles. This is more plausible when you realize that bicycles were more of a hobby for entertainment before they became a practical means of transportation.
+ Cultural factors. Maybe there was just a general lack of interest in useful mechanical inventions until a certain point in history? But when did this change, and why?
These are all good hypotheses. But some of them start to buckle under pressure:
The quality of roads is relevant, but not really the answer. Bicycles can be ridden on dirt roads or sidewalks (although the latter led to run-ins with pedestrians and made bicycles unpopular among the public at first). And historically, roads didn’t improve until afterbicycles became common—indeed it seems that it was in part the cyclists who called for the improvement of roads.
I don’t think horses explain it either. A bicycle, from what I’ve read, was cheaper to buy than a horse, and it was certainly cheaper to maintain (if nothing else, you don’t have to feed a bicycle). And it turns out that inventors were interested in the problem of human-powered vehicles, dispensing with the need for horses, for a long time before the modern bicycle. Even Karl von Drais, who invented the first two-wheeled human-powered vehicle after the Year without a Summer, had been working on the problem for years before that.
Technology factors are more convincing to me. They may have been necessary for bicycles to become practical and cheap enough to take off. But they weren’t needed for early experimentation. Frames can be built of wood. Wheels can be rimmed with metal. Gears can be omitted. Chains can be replaced with belts; some early designs even used treadles instead of pedals, and at least one design drove the wheels with levers, as on a steam locomotive.
So what’s the real explanation?
(Continue reading. 2,184 words and lots of great bicycle pictures.)
This post is a single piece from Jason Crawford's project, The Roots of Progress, aptly named, to understand the nature and causes of human progress. I haven't thought deeply enough to check his research, but it's a fascinating project. This essay examines a specific piece of technology, but the case study is used to develop and support models of what it takes for progress to occur.
That someone happens at some point rather than another point is an interesting question to explore but is also one that probably seldom has good answers. Still, intellectual curiosity is a goal in self.
I wonder if a better starting point for the inquiry might not actually be why the invention was invented when it was -- why the inventor made the effort in the first place. What problem was being solved. We can then look at various limiting factors to see if they would have made the effort futile if done at some earlier period of time.
That might help place some markets in history on when the invention became feasible.
But the question seems to have the two parts:
1) When the realities of the world support such an action/invention.
2) When does someone have that "oh, duh" moment when they thing "We could do this [easier] if X were present and I can figure out how to have X."
We can reasonably get answers to the first part. I think for the second part we will find that more challenging.
A related question might also be about inventive thoughts and vision that were impossible at the time they were thought and theoretically designed and what role they had an shaping the future.
That reminds me lyrics in an old song (old as in 80 or 90s not 1500s ;-) "if you cannot change the world change yourself. if you cannot change yourself, change the world"