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Bicycle Technology (1973) [pdf]

60 points| BeniBoy | 7 years ago |veterancycleclublibrary.org.uk | reply

31 comments

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[+] forapurpose|7 years ago|reply
> The thin-walled tube of circular cross section is a most efficient structural member; it can resist tension or compression, bending, torsion, or the combination of stresses that are exerted on the frame of a vehicle. Although for bending in a particular plane an I-section joist may be more efficient, if bending load can be applied in any plane, then the thin tube is to be preferred. It is for this reason that tubes are used as a strut or compression member in which failure could occur by elastic instability, or bowing. For torsion there is no better section, hence the tube is the typical main transmission shaft of an automobile. The stem of the bamboo plant is an excellent example of the properties of a hollow tube ...

I notice that many current bikes have flattened, non-tubular frame components. Why? Style? New materials? I would assume, knowing little about it, that the tube shape would generally retain its advantages regardless of the material. But perhaps the new material doesn't form tubes well?

[+] analog31|7 years ago|reply
I think the answer is aluminum. Note that I'm not an engineer, just a physicist. As I understand it, aluminum has different mechanical properties such as strength to weight ratio, and how it behaves when flexed. So it may require a different design approach to produce a strong but light frame. At the same time, it's easy to hydroform aluminum (blow it out into a mold using high pressure fluid), so you can in fact design a wider variety of shapes at a tolerable cost. And if you're going to engineer the shapes of the tubes, then why not make it look cool too.

I own one aluminum bike, relatively low end and not super lightweight... but it does look cool. ;-)

[+] Someone|7 years ago|reply
Aerodynamics an/or looking aerodynamic and/or distinguishing a brand by showing of what you can build.
[+] avhon1|7 years ago|reply
Closely related (and even briefly shown in the video) to the description of a computer as a bicycle for the mind: https://www.youtube.com/watch?v=xqxWlvJ35yk
[+] SketchySeaBeast|7 years ago|reply
I don't really care for that metaphor, while it does make sense at a base level, I feel like it doesn't quite fit. A bicycle is (once constructed) entirely man powered - it only goes as well as we are able to power it.

The computer is more of a car for our minds - they run on electricity/gas, take minor low effort inputs from us, and transform them into massively larger outputs not due to simple mechanical laws, but because of a secondary source of impetus. There isn't that 1:1 input/output that a bike has.

[+] forapurpose|7 years ago|reply
Does anyone know the source for this? I found a Scientific American article and an Amazon listing for an out-of-print book published by Scientific American (perhaps just a copy of the article).

https://www.scientificamerican.com/magazine/sa/1973/03-01/#a...

https://www.amazon.com/Bicycle-technology-S-S-Wilson/dp/B000...

EDIT: The URL includes 'Scientific American March 1973', which matches my first link. EDIT2: So I think that must be the source.

[+] mikestew|7 years ago|reply
I don't know what you're looking for. Your own research has brought you to a page from which you can purchase a digital copy of the whole magazine for $8. What do you want, a printed copy?
[+] fergie|7 years ago|reply
Hub gears still seem like witchcraft.
[+] mikestew|7 years ago|reply
Once you take one apart, it becomes more obvious. Best of luck getting it back together, however.
[+] dvh|7 years ago|reply
No. That is reserved for sewing machine.
[+] denimnerd|7 years ago|reply
rohloff has a 14 speed hub
[+] forapurpose|7 years ago|reply
The bicycle was, arguably, a bit too late. Imagine how cities would be constructed today if bicycles (with modern functionality and affordability) had predated cars by 50 years.

Imagine people trading in their horses for bicycles, for much easier care, less pollution, much smaller and flexible (it seems to me) alternatives. Imagine the variety of bikes people would come up with, lacking alternatives: Personal transport, of course, but also cargo, long-haul, rough terrain, tandem/triple/etc when more power is needed, rickshaws, etc.; with bikes already being the established 'first mover', would we use cars for as many purposes as we do today? Imagine how cities would be constructed, providing for bikes first, with the car fitting in later - from roads to locations of retail and transit.

For some things you still may have needed horses, such as pulling heavy loads. Also, I wonder if the terrain and roads would have suited bicycles (cobblestones and muddy roads probably aren't so great to ride on) and, if not, if people would have invested in the infrastructure; beware the modern myopic perspective about cities - back then almost everyone lived in rural areas. Finally, in some less economically developed parts of the world bicycles did become immensely popular before cars, IIRC; I wonder how these issues played out there.

[+] Xylakant|7 years ago|reply
> Imagine the variety of bikes people would come up with, lacking alternatives: Personal transport, of course, but also cargo, long-haul, rough terrain, tandem/triple/etc when more power is needed, rickshaws, etc.; with bikes already being the established 'first mover',

This did happen: Bicycles used to be the primary mode of transport for many many people even in Europe. It certainly was in China and other parts of Asia. Long John Style Cargo bikes - the type that Bullit for example builds - were conceived in the early 1920ies. Butchers/Barkes Bicycles were common until the 1950ies in Europe. Cars were a luxury back then, common people used bicycles, walked or used public transport.

I think that electric assistance is what will drive a renaissance of cycling as a mode of transport if infrastructure can be provided that makes cycling in cities safe and enjoyable. It allows sufficiently high speeds to achieve reasonable transport times even on medium distances for most people.

[+] mikestew|7 years ago|reply
Imagine people trading in their horses for bicycles, for much easier care, less pollution, much smaller and flexible (it seems to me) alternatives.

You've just copy-and-pasted Columbia's ad text from the late 1800s. The problem was not that bicycles were too late, but that bicycles were out of reach for the common working man for quite a while. Multi-speed, shaft-drive bicycles with pneumatic tires were available in the 1890s. They were also priced like Teslas.

Source: have been a member of the U. S. counterpart to the Veterans Bicycle Club (where this article came from) since I was a kid.