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Alan Turing using math to repair his bike

mathmutation.blogspot.com

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Re: Alan Turing using math to repair his bike

#11

Post by dTal »

avg_dev wrote: post #2

> And in Turing’s case, it was further complicated by the fact that he always wore a gas mask as he rode, to prevent triggering his allergies. But the alarm clock he was known to wear around his waist might have helped. What? Is that for real? Edit: It is! > He loved to ride his bicycle through the countryside. To time himself, he would simply tie an alarm clock around his waist. During the war, according to I.J. Goo…

I wonder which part of this (admittedly odd fashion statement) seemed surprising to you? Gas masks were of course ubiquitous during the war, so this was probably only about as eccentric as wearing an N95 mask would seem now. And the alarm clock seems like a fairly practical if whimsical hack in an age when chronometers would have been mechanical, and therefore quite expensive.

Re: Alan Turing using math to repair his bike

#13

Post by analog31 »

fyhn wrote: post #7
BeniBoy wrote: post #6

Kind of reminded me of the traditional wisdom that you should select chains and sprocket to avoid patterned wear. I don't know if there is an effect (especially with bikes and their low torque),but I always think about it when changing my chain. I suppose this only applies to single sprocket bike.

Isn't this only relevant for fixed gear bikes, where you can skid the rear wheel to brake, and you want maximize the number of possible "skid patches", or orientations of the rear wheel while the pedals are in a fixed position?

It could also apply to the wear on the chainring and cog if their teeth are in a perfect proportion to one another, but without thinking too hard about it, I'm guessing that's actually rare. For instance a 2:1 ratio would be awkward for most cyclists riding on pavement (too low) and 3:1 too high, if they had to choose exactly one ratio.

I ride 46:19, because those are the parts that were in my bin when I built the bike, and it's a pretty good all-round ratio for city riding unless you're a lot more athletic than I am.

Also, those components wear out soon enough anyway -- a chain lasts 2 to 3 thousand miles, and a cog lasts a few chains.

Re: Alan Turing using math to repair his bike

#14

Post by natly »

avg_dev wrote: post #2

> And in Turing’s case, it was further complicated by the fact that he always wore a gas mask as he rode, to prevent triggering his allergies. But the alarm clock he was known to wear around his waist might have helped. What? Is that for real? Edit: It is! > He loved to ride his bicycle through the countryside. To time himself, he would simply tie an alarm clock around his waist. During the war, according to I.J. Goo…

Wasn't he a long distance runner. I wonder if he wore it then too.

Re: Alan Turing using math to repair his bike

#15

Post by avg_dev »

dTal wrote: post #11
avg_dev wrote: post #2

> And in Turing’s case, it was further complicated by the fact that he always wore a gas mask as he rode, to prevent triggering his allergies. But the alarm clock he was known to wear around his waist might have helped. What? Is that for real? Edit: It is! > He loved to ride his bicycle through the countryside. To time himself, he would simply tie an alarm clock around his waist. During the war, according to I.J. Goo…

I wonder which part of this (admittedly odd fashion statement) seemed surprising to you? Gas masks were of course ubiquitous during the war, so this was probably only about as eccentric as wearing an N95 mask would seem now. And the alarm clock seems like a fairly practical if whimsical hack in an age when chronometers would have been mechanical, and therefore quite expensive.

I didn't know about the gas masks being ubiquitous during the war; that makes that part a little less surprising. History can be sad.

Re: Alan Turing using math to repair his bike

#19

Post by donthellbanme »

avg_dev wrote: post #2

> And in Turing’s case, it was further complicated by the fact that he always wore a gas mask as he rode, to prevent triggering his allergies. But the alarm clock he was known to wear around his waist might have helped. What? Is that for real? Edit: It is! > He loved to ride his bicycle through the countryside. To time himself, he would simply tie an alarm clock around his waist. During the war, according to I.J. Goo…

For years before Covid, I would wear a N95 mask while doing yard work, construction, biking, and even night walks.

I got some stares.

For awhile, I felt some of my neighbors thought I was trying to conceal my identity; but it was just for allergies.

The last thing I wore it for was germs.

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