Bikes benefit a lot from pneumatic tyres, pressure pumps, smooth asphalt (not cobbles), precision engineering of chains, chemistry of oils and lubricants, rust-proof steel, rubber brake pads with compounds that last long enough and resist rain, spring steel for suspension, cables that don't stretch. Without those things you get a wooden boneshaker hobby-horse, large, heavy, energy inefficient, incovenient: https://duckduckgo.com/?q=hobby+horse+victorian+bike&t=ffab&...

(And internal combustion engines; how are you going to distribute them around the Roman Empire by the tens of millions without trucks or ships?)

To expand on one of those things - bike chains get slightly longer as they wear out. Once it's about 1% longer than it started, it looks about the same as it always did, but it's starting to damage the drivechain and you need to replace it. An ancient Roman blacksmith has no hope of making a chain with anything like that level of precision.

you would have used leather belts. it would have been a pita, they stretch pretty fast...but its feasible I think.

Yeah. The vast majority of parts on a bicycle are the individual links in a chain. Manufacturing these to sufficient tolerance is quite challenging.

Romans might have been able to do shaft-drive. Or Penny-farthings (direct pedal-wheel drive).

I believe you only have this problem if your bike has gears based on a set of sprockets (different size chainwheels and a derailleur to move the chain from one to the other).

In Europe (Holland in particular), people ride single gear city bikes (or internally geared hubs) for decades without replacing chains or cogs. When you only have one chainring and one cog, they wear along with the chain, and it takes a very very long time to encounter problems.

It's when you have the sprocket cluster with multiple cogs that are not all wearing equally, that you get problems. Or often the problem on geared bikes doesn't appear until you replace your worn chain and the new chain no longer meshes well with the cogs worn to match the old chain.

Or in any flat hipster city. Melbourne (now Canberra) representing!

I ride my single speed (not fixed) every day. It’s my most beloved possession.

Wouldn't the chain still need to be quite intricate and pretty hard to make even then? Though now that I think about it, you could probably make it in a way similar to chainmail, since tight tolerances aren't actually that crucial (the results would suck, but only compared to modern bikes). Though the other parts might be just as hard to make and especially to fit together (the bearings, the gearing for the chains...)

Bronze bushes work for bearings (still needs a lathe/ but not ball bearings). Chains can be belts of horsehair (or any civilisation with wire, tube and sheet metal can make a modern chain) or a treadle works okay. Spokes can be wooden.

The main limiting factor is probably the pnuematic tyre and smooth roads.

Nope, with single speed/hub gears chain wear is still a problem, it's just that they're less sensitive to it and there's fewer parts to replace. When the chain gets longer it gets loose, but it has to be very loose indeed to fall off or skip on a single speed. With a derailleur setup there's a tension arm with a weak spring so when the chain wants to skip that tension arm lets it. Derailleur setups commonly have some cogs with fewer teeth than single speeds so the problem is more obvious. Also, often derailleur cogs are aluminium while single speed ones are steel (not always!).

Typically a safety bike will get through 3-5 chains before needing to replace the rear cog, and many more before replacing the chainring(s). But Pinion gearboxes in the bottom bracket often run small chainrings that are similar in size to the rear cog, and I suspect they need to replace both rather than just the rear one.

I ride a bicycle with a hub gear as my main form of transport. About two years ago, I noticed the sprocket (rear cog) was getting very worn, so I removed it so I could reverse it and let it wear on the other side of the teeth (standard procedure for this sprocket to extend the wear life). But I accidentally put it back the same way as before and didn't notice until recently when I changed the hub oil. I had no problems with the chain skipping, despite the heavy sprocket wear (although it's now worn to the point that I no longer feel comfortable letting it wear on the other side of the teeth, so I'll have to buy a new sprocket). But you are correct that the chain wears more than the sprocket; I've already replaced the chain a few times.

https://ibb.co/0sJx4SN (new cog on the left, old on the right)

I'm not saying you should do this. And Rohloff strongly suggest you don't do this I'm just saying that you can do this.

The other factor is that single-speed/hub-gear chains are wider, so tend to last a lot longer.

You don't have to use chains though, you can have pedals on the front wheel, like the original bikes, or not pedal at all, just push yourself on the ground

Penny farthing bikes are death traps. Bikes that have similarly sized wheels with pedals on the front wheel aren't practical enough to be better than walking. Bikes without pedals are also not practical.

They were both more efficient than walking. Humans will put up with death traps if it means more efficiency in transportation (just look at car fatalities). The only reason they didn't took off faster was the lack of roads. And by the time we had tarmac roads bikes already evolved to have chains and read drive.

Watch a kid on a balance bike and tell me how it's not practical, lol. A 4 year old can bike around a whole park in seconds.

also there are other ways to transmit power than a chain (belt, shaft etc).

Chains don't stretch, they wear down. When measuring a chain, you measure the distance between links to see how much material has worn away. The links don't actually get longer from stretching.

https://youtu.be/gXd-3UnqoaM

The key invention that made them possible was ball bearings. This is why the modern bicycle and the modern car were invented within a year or two of each other.

...and roads, which were created for use by horses and carraiges.

Yep, 90% materials, and so are other things like windsurfing, paragliding, etc.

Very little of the "modern stuff the ancients didn't figure out" could be done without modern materials.

If dumped back in time, maybe you could make rent teaching swimming or doing accounting. Medicine would probably be too dangerous.

Yeah. Surfing is a great example of a Stone Age sport that has been radically changed by Space Age technology. Koa wood gets you a longboard that is hard to steer and can only surf long smooth waves. The modern surfboard is very much born out of California's aviation industry and its fixation on light, strong materials and aerodynamics. Surfing Pipeline is only possible with modern plastics, fins and shaping.

> Bikes benefit a lot from […] smooth asphalt (not cobbles)

Bicycle riding societies were some of more vocal proponents on paved roads (predating the automobile):

* https://www.vox.com/2015/3/19/8253035/roads-cyclists-cars-hi...

* https://www.theguardian.com/environment/bike-blog/2011/aug/1...

* https://www.smithsonianmag.com/travel/american-drivers-thank...

And now of course some of the most prestigious races in the professional cycling world are across predominantly cobbled roads as a form of torture for those racing.

https://cdn.mos.cms.futurecdn.net/hD4Vtdmow7B4Jf4XiWPH5g.jpg

Also lots of competition on non-paved roads:

* https://en.wikipedia.org/wiki/Cyclo-cross

As a former (and not great) CX racer, this sport should not be talked about, as it's a cruel beast to those who dare and try.

(Kidding, of course, it's a wildly entertaining form of racing)

And MTB and Gravel racing, of course.

With the most exciting Sunday in the entire year of racing coming up!

On a well-made steel crossbike or touring bike, rough roads and dirt roads are a downright joyful experience.

Well, I've got a bike from the 30s and it's perfectly fine for everyday riding. While I agree that most of those things you listed are valuable and convenient, good enough is often just good enough. Like I've got no use for any cables and I don't need precision engineered chains.

* * *

It takes a LOT more calories to power a horse than a biker.

On a cretan mountain path with before christ technology?

There's a reason that horses were the fancy sports car/military tool of the animal transport world. They eat a lot, break easily, and don't last long.

People used oxen, donkeys, llama etc way more than horses. And the Chinese invented wheelbarrows and used them extensively rather than using draft animals. They often use bicycles much the same way as wheelbarrows now, and rich people often find that amusing (possibly because a KMart bike is a toy, a Chinese bike is a workhorse).

Agreed. Bicycles are kind of a miracle of seeming simplicity hiding a ton of important developments of the industrial age. 99 Percent Invisible did a recent episode on just this topic: https://99percentinvisible.org/episode/the-safety-bicycle/.

I guess perspective makes it a lot less surprising that the first airplanes were made by bicycle manufacturers.

Don't even get me started on airplanes though - there was only 66 years between the first airplane (Wright Flyer in 1903) and the moon landing (1969).

Disclaimer: that's of course a cool anecdote on the surface, but rockets have been around since the 13th century so they're two mostly different technologies.

Are rockets and planes related? Quite different requirements regarding aerodynamics and propulsion.

It's all the same, just that the density of the fluid the vehicle is traveling in changes.

So a submarine is the same, again?

Key development for flight: Wings which carry the plane. First planes didn't even have an engine (besides human)

Key development for rockets: Strong powerful engines to escape gravity. Aerodynamics matter relatively little, mostly for heat control.

I don't know how related the development of jet engines and rocket engines was. Of course things like the Space Shuttle, which has some airplane-like aerodynamic steering tie both together ...

We're playing a bit fast and loose with our phrasing here if we want to split hairs about the development of these technologies.

Powered, navigable, human flight existed before the development of wings.

The early rockets mentioned above weren't for human flight, nor for spaceflight. Rockets were developed to be terrestrial weapons, not to propel humans.

Rocket engines and turbine engines are both a type of jet engine. These engine technologies themselves weren't developed together because one was developed to make airplanes go higher and faster, and the other was developed to stab people with arrows better. If what we're really talking about is "human flight", then rockets and turbine engines were both used to propel humans on airplanes before anyone started considering spaceflight.

And then when humans did consider spaceflight, humans were developing space planes and tubular orbital rockets at the exact same time. The X15 flew 2 years before Vostok 1.

The people developing human flight were always interested in going faster and higher. The technologies they experimented with were intermixed the whole time.

Thanks for the long response really appreciated!

You will be amazed to know that the Ball Brothers, who invested the Mason Jar/Atlas Jar, and perfected canning and soups... is also Ball Aerospace - who makes super-high end space components for the MIC, black projects, skunkworks, NASA etc...

All from the Mason Jar.

https://www.visitmuncie.org/a-legacy-etched-in-glass-the-bal...

(also "Aliens")

Ball-bearings? Primitive?? Surely you jest!

A parallel thought is that the first airplane is the product of bicycle mechanics and not railway or automotive mechanics. As others pointed out, there are a lot of necessary technologies like rubber, bearings, lubricants, sprockets and chains that need to be developed, but there is also something very elegant about bicycles. If you start to mess around with a 70's era road bikes you get a sense of just how perfectly everything needs to fit together and how everything affects everything else. (You see it more clearly in older bikes because you need to deal with non-standard parts). I think I learned more about bicycles from the royal pain of a 1982 Peugeot than anything else. This is not to say that a car doesn't have similar complexity, but the use of chemical fuel and 4 wheels masks how the tunings fit together. With my current bike there is a serious difference when it is perfectly tuned.

The production of quality steel isnt thousands of years old.

Yeah they could produce small items - but to make the steel of the quality needed for bicycles is pretty new - the past 150-200 years with the Bessemer process

They could've just made them out of carbon fiber composites before /s

Bicycles are a relatively new invention because they require roads/flat paths which are also a relatively new occurance, and came about due to the widepread use of horses and then carraiges for transportation.

A bike at any other point in human history would have been completely useless trying to traverse natural terrain.

The modern "fat bike" would be (is!) quite good at traversing a variety of natural terrains where humans live, without roads or paths/trails.

"Roads? Where we're going, we don't need roads."

. o O ( Now if only 18.8 MPH were enough to activate the flux capacitor. )

Mountain bikes do not require roads or flat paths; they work fine on trails (hence the name "mountain bike"), which have existed since large animals evolved.

However, mountain bikes arguably require even more technologies than other bicycles, especially for suspension and brakes (MTBs pioneered the use of disc brakes on bicycles).

I always loved the scene in HBO's Deadwood when the first bicycle comes to town and everyone gathers to watch someone try and ride it.

No shit, you can make an airplane if you know your way around a bicycle as the wright brothers demonstrated. They were bicycle mechanics originally.

The safety bicycle (chain, pedals in the middle) is about a decade newer than the car (under 150 years), although they hit mass production within a year either side of each other depending in how you define it.

> Bikes seem like such a primitive technology, and yet as this article demonstrates, it takes a lot of engineering to design even primitive products.

Very strange. I get that we take things for granted if they've been around forever (ie. since before we were born). But I never considered bicycles "primitive". What makes you think that? Is it because they don't need electronics? What is a non-primitive transport technology?

The timing of the invention of the bike is discussed here: https://rootsofprogress.org/why-did-we-wait-so-long-for-the-...

He settles on general economic and cultural factors. Experimentation requires there to be enough people with spare time and resources to play around with things with no immediately obvious payback.