Comments on: 09/17/2012 – Random Shop Talk http://yehudamoon.com/09172012/ Fri, 17 May 2013 14:52:16 +0000 hourly 1 http://wordpress.org/?v=3.4.1 By: oldfieldcycles http://yehudamoon.com/09172012/#comment-56045 oldfieldcycles Sat, 22 Sep 2012 02:58:31 +0000 http://yehudamoon.com/?p=3485#comment-56045 overinflating your tires is bad news. it shortens your tires life, makes them roll poorly and can possibly blow out your rim. i used to really like smaller profile tires with high pressure, but in the last few years i have been riding a randonneur bike with 700x32 tires inflated to 70psi and the bike rolls just as fast, is more stable, and tons more comfortable. also, i have no evidence to back this up, but i think lower psi reduces pucture flats. overinflating your tires is bad news. it shortens your tires life, makes them roll poorly and can possibly blow out your rim. i used to really like smaller profile tires with high pressure, but in the last few years i have been riding a randonneur bike with 700×32 tires inflated to 70psi and the bike rolls just as fast, is more stable, and tons more comfortable. also, i have no evidence to back this up, but i think lower psi reduces pucture flats.

]]> By: Dave Dunn http://yehudamoon.com/09172012/#comment-55963 Dave Dunn Wed, 19 Sep 2012 20:05:57 +0000 http://yehudamoon.com/?p=3485#comment-55963 The helmet has nothing to do with the story. The scuffle led to his death. The helmet has nothing to do with the story. The scuffle led to his death.

]]> By: Dave Dunn http://yehudamoon.com/09172012/#comment-55962 Dave Dunn Wed, 19 Sep 2012 20:03:54 +0000 http://yehudamoon.com/?p=3485#comment-55962 No matter what the mode there will always be energy lost in producing motion. Just because you hear a train does not disqualify the steel wheels as the the most effficient wheels. Sound is very easy to produce with little mechanical input si I wouldn't worry too much about it at train weights. If a bike made that much noise I'm sure we could locate a huge unauthorized energy-eating source for it. No matter what the mode there will always be energy lost in producing motion. Just because you hear a train does not disqualify the steel wheels as the the most effficient wheels. Sound is very easy to produce with little mechanical input si I wouldn’t worry too much about it at train weights. If a bike made that much noise I’m sure we could locate a huge unauthorized energy-eating source for it.

]]> By: Widsith http://yehudamoon.com/09172012/#comment-55906 Widsith Tue, 18 Sep 2012 16:00:22 +0000 http://yehudamoon.com/?p=3485#comment-55906 I run the rated psi too, or slightly above. I run the rated psi too, or slightly above.

]]> By: Opus the Poet http://yehudamoon.com/09172012/#comment-55876 Opus the Poet Tue, 18 Sep 2012 05:38:18 +0000 http://yehudamoon.com/?p=3485#comment-55876 I have been to scared to run the 23mm front tire on my modified Stratus under 60 pounds outside of coast-down tests, but I didn't get any significant reduction in speed until the pressure was under 30 pounds (my gauge doesn't even come off the peg until 30 pounds, so how far "under" 30 it really was is a matter of conjecture). I modified the Stratus from a 28-451 to 23-622 front wheel and it carries so little weight up front with me riding it that I can almost ride my Specialized Armadillo without a tube. Basically 60 pounds is where I start getting concerned about rolling the tire off the wheel. I have been to scared to run the 23mm front tire on my modified Stratus under 60 pounds outside of coast-down tests, but I didn’t get any significant reduction in speed until the pressure was under 30 pounds (my gauge doesn’t even come off the peg until 30 pounds, so how far “under” 30 it really was is a matter of conjecture). I modified the Stratus from a 28-451 to 23-622 front wheel and it carries so little weight up front with me riding it that I can almost ride my Specialized Armadillo without a tube. Basically 60 pounds is where I start getting concerned about rolling the tire off the wheel.

]]> By: perthcyclist http://yehudamoon.com/09172012/#comment-55872 perthcyclist Tue, 18 Sep 2012 01:14:50 +0000 http://yehudamoon.com/?p=3485#comment-55872 I like to run my roadie at about 100psi, but have been known to go down to 80psi when I know I'm riding rough roads with lots of glass, I seem to get less flats that way. I am not heavy enough to pinch flat until far below 80... since I've never pinch flatted a road tyre, and have run them as low as 60 when I've been lazy and not pumped them up. I like to run my roadie at about 100psi, but have been known to go down to 80psi when I know I’m riding rough roads with lots of glass, I seem to get less flats that way. I am not heavy enough to pinch flat until far below 80… since I’ve never pinch flatted a road tyre, and have run them as low as 60 when I’ve been lazy and not pumped them up.

]]> By: Kapusta http://yehudamoon.com/09172012/#comment-55871 Kapusta Mon, 17 Sep 2012 20:48:32 +0000 http://yehudamoon.com/?p=3485#comment-55871 Thistle is hot, period. Thistle is hot, period.

]]> By: William M. deRosset http://yehudamoon.com/09172012/#comment-55870 William M. deRosset Mon, 17 Sep 2012 20:34:31 +0000 http://yehudamoon.com/?p=3485#comment-55870 Dear Tencon, Well, the mechanism of rolling resistance for rail stock is well-understood. See Bicycling Science, 2nd edition for one (secondary) discussion. Steel wheels rolling on steel rails is very efficient compared to rubber tires etc. Flexible tires with significant hysteresis (like bike tires) riding over irregular surfaces are harder to quantify analytically, and the published studies that are useful in the real world have been thin on the ground. Best Regards, Will William M. deRosset Fort Collins, CO Dear Tencon,

Well, the mechanism of rolling resistance for rail stock is well-understood. See Bicycling Science, 2nd edition for one (secondary) discussion. Steel wheels rolling on steel rails is very efficient compared to rubber tires etc.

Flexible tires with significant hysteresis (like bike tires) riding over irregular surfaces are harder to quantify analytically, and the published studies that are useful in the real world have been thin on the ground.

Best Regards,

Will
William M. deRosset
Fort Collins, CO

]]> By: Leslie http://yehudamoon.com/09172012/#comment-55869 Leslie Mon, 17 Sep 2012 17:41:44 +0000 http://yehudamoon.com/?p=3485#comment-55869 No and yes: if you stick to the same skinny tire and drop the psi, then yes, you'll be more sluggish and have more snakebites. But if you go to a fatter tire, then you can run at a lower psi and still not have snakebites; you can't just drop the psi on the skinnies and expect success. The downside to this is, a lot of 700c bikes these days just can't run anything as large as a 28c, are stuck w/ 23c or 25c; you have to run those w/ a higher psi. My 700c bike, I'm running a 28c in front, a 32c in rear, w/ fenders, and can run at a bit lower psi for it. ('course, my 650b is getting most of my saddle-time right now, covering mixed surfaces...) No and yes: if you stick to the same skinny tire and drop the psi, then yes, you’ll be more sluggish and have more snakebites. But if you go to a fatter tire, then you can run at a lower psi and still not have snakebites; you can’t just drop the psi on the skinnies and expect success. The downside to this is, a lot of 700c bikes these days just can’t run anything as large as a 28c, are stuck w/ 23c or 25c; you have to run those w/ a higher psi. My 700c bike, I’m running a 28c in front, a 32c in rear, w/ fenders, and can run at a bit lower psi for it. (‘course, my 650b is getting most of my saddle-time right now, covering mixed surfaces…)

]]> By: BHNelson http://yehudamoon.com/09172012/#comment-55868 BHNelson Mon, 17 Sep 2012 17:15:31 +0000 http://yehudamoon.com/?p=3485#comment-55868 I dunno... that endo slowed me from 22-0 mph in less than 2 seconds! I dunno… that endo slowed me from 22-0 mph in less than 2 seconds!

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