Posted on 12/04/2022 2:48:09 AM PST by Berlin_Freeper
Welcome to The Bicycle Thread. A monthly PING List for bicycle enthusiasts to share experiences, information and ideas.
I guess bikes are racist, too.
I guess bikes are racist, too.
= = =
What color are the tires?
They are located at the lowest part of the bike.
They are forced against the ground/pavement.
Yep.
Ping!
There are western organizations attempting to bring modernization to remote parts of Africa -- the most primitive places on earth -- in the form of the bicycle because it's the lowest cost and lowest tech means of reducing the time it takes common folk to travel between villages.
Which in effect is democratizing commerce because it provides opportunity to the poor to travel farther for work, or to the aspiring entrepreneur to distribute his merchandise over a wider market.
To hold down the manufacturing costs some of them are building their bicycle's frames from bamboo they harvest locally at little or no cost. The only thing they absolutely have to source from outside the village is the stuff that has to be made from metal (or, alternatively, carbonfiber) and the rubber bits.
And if you've seen an episode of Gilligan's Island, you know that a bicycle also can be used to power everything from a washing machine to (a generator to power) a transistor radio. ;-)
If you haven't seen this video, you should. I consider it the most comprehensive and most understandable bit about how much energy cyclists expend, and where exactly that energy goes, that I ever have come a cross. It's from a series done on PBS back in the '80s by Dr Philip Morrison titled, "The Ring of Truth." Morrison was a communist but he also was a Manhattan Project scientist so his physics bona fides are impeccable.
https://www.youtube.com/watch?v=Nk8CQNThbc0
Start at the beginning if you want to follow his explanation of how science arrives at these answers, or FF to 21 minutes to get to the part dealing specifically with cycling. He doesn't do the math in the video but the figures he mentions show that about 72.5% of the calories a TdF racer expends in a typical stage (+/- 10.5%)* is converted to heat (= wasted). And they couldn't possibly produce the sustained pedaling forces** they do without the wind their speed creates preventing them overheating.
There's some really neat TdF footage mixed in from the Lemond/Hinault era. And glamor shots of some vintage Campy Record stuff.
In case you're wondering, Morrison contracted polio at age four, which left him bent-over and wheelchair-bound in his latter years.
* 20-25 JDUs (@250 calories per) out of 30-32 total JDUs
** I once had a physics professor who taught that the bicycle is the most efficient form of human (land) transportation that exists because it's the fastest man-powered vehicle. Nothing else can sustain a higher speed unless it has a second engine (in addition to the human) and the need to fuel the second engine puts it beyond the point of diminishing return on energy.
Point of fact, cyclists can and do ride clean across America, from sea to shining sea (in the RAAM), in as little as eight days. These obviously are exceptional individuals, however, their average speed (which includes sleep breaks) is only about 14 mph (22 kph). Any common schlub who is able-bodied and reasonably healthy can achieve the conditioning necessary to maintain 14 mph for several consecutive hours. And without the energy expense of a second engine. And with a considerable reduction in their beltline, without dieting.
In commenting about the average speed they rode their bikes, they rode their bikes pretty fast every time they got on their bikes, but as those hours ground away and as they became exhausted that they started getting slower and slower to the point where they were riding them about as slow as they could with out falling off or getting cramped up to much. At least that is how I remember it about ?40 years ago.
My app says I rode my bicycle 2,527 miles last year and 2,878 miles this year.
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