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Let the Laughing Begin
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Let the Laughing Begin
On Tuesday, September 5, 2017 at 8:43:40 AM UTC-7, Frank Krygowski wrote:
On 9/4/2017 4:00 PM, wrote: [I responded to this earlier, and it shows up in my "Sent" folder, but never made it to the group. I don't know why. Maybe it had something to do with my internet speed test showing approximately zero for upload speed? Thanks, AT&T.] Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? I've done that several times. Oddly enough, I did it once in error. "This book contains at least one error, but this may be it." - Peter van der Linden, "Expert C Programming" (LOL yea, rite, Peter! Cute quote tho- :) |
Let the Laughing Begin
On Tue, 5 Sep 2017 07:04:41 -0700 (PDT), wrote:
On Monday, September 4, 2017 at 7:32:25 PM UTC-7, John B. wrote: On Mon, 4 Sep 2017 13:00:34 -0700 (PDT), wrote: Yesterday I went on a long enough ride and the weather report turned out to be incorrect enough that I was close to heat prostration near the end. I hit a stone in the road that was invisible and it gave me a flat. As I was trying to figure out how to make the particular CO2 filler in that seat pack to work I punctured the canister and lost one of my two CO2 tubes. Opening the front tire to remove the inner tube and replace it with the new tube a black guy who looked nearly homeless came by and said that he had a patch kit if I needed it. I thanked him but without a pump I couldn't find any leaks to patch. When the front tube came out it was a Performance butyl tube. They were available in a 30, a 40 and a 60 mm stem length. I have bought the latex tubes because they were available in 51 mm stems. The back (which was losing air about the same as the front) is latex. So my tires not losing air plainly isn't because of the material of the tubes. My suspicion is the pump meter. I bought a new Silca professional pump from Andrew and it has a new (and probably much better) pressure gauge on it. This allows me to fill the tire up properly and to test the pressure more accurately than most pumps. So it probably is pump and not inner tube material related. Now don't say I lacked the courage to publicly correct myself when I think I was wrong. How many of you can say the same thing - John and Frank? Actually I don't remember ever saying that you failed to correct yourself. If memory serves what I've said was that "you are wrong". And as usual you didn't know what you were talking about. As someone wrote, "Reality is anything you want it to be. Just close your eyes and let your imagination run wild." -- Cheers, John B. |
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On Tue, 05 Sep 2017 09:52:07 -0700, Jeff Liebermann
wrote: On Tue, 5 Sep 2017 07:04:03 -0700 (PDT), wrote: On Monday, September 4, 2017 at 9:25:51 PM UTC-7, Jeff Liebermann wrote: On Mon, 4 Sep 2017 14:01:39 -0700 (PDT), wrote: The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Here's my bicycle pump tester: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/Bicycle%20pump%20pressure%20gauge.html I scribbled a little about how it's used in a previous postings: https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/CoySfXtGAQAJ https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/XeXJLe5kAQAJ For a leakdown test, I attach a small pressure vessel to one port, and pump up the pressure with a bicycle pump attached to the other port. Then, I watch the pump gauge to see if it remains stable. If the test gauge leaks, I paint the plumbing with bubble mix looking for the source of the air leaks. If the gauge itself is suspect, I take it apart and check the mechanism for leaks. Well, that certainly seems a better method than getting a good pump to begin with. Quantity is my substitute for quality. When I tested my collection of floor and frame pumps, I found a few defective pumps and a few inaccurate gauges. I don't recall the numbers, but one gauge read 8 lbs low for a 60 lb tire pressure. Cleaning the crud out of the mechanism most fixed that. I don't think I own anything that might resemble a "good pump". This was from 3 years ago: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/bicycle-pumps.html I now have about twice as many frame pumps. I also have 4 working floor pumps, 2 sick floor pumps, 1 worthless foot pump, and maybe a dozen assorted pencil, analog, and digital gauges. The various cheap automotive type digital gauges seem to be the most consistent and accurate, but also have mechanical problem, such as fitting only Schrader valves or a leaky fit. Maybe, some day I'll buy a "good pump" and recycle all the junk pumps. A proper dead weight pressure gauge tester/calibrator is not in my budget (although I could probably build one). Incidentally, when I go for rides these daze, I generally throw the bicycle into my Subaru and drive to where I want to ride. Before leaving, I usually top off my leaky tires with some air from a cheap 12V automotive air tire pump. The one I have has an automatic shutoff when it reaches a set pressure. I just set the dial, start the air compressor, and I'm ready to ride when it's done. The problem is that it's horribly inaccurate. The dial settings and built in pressure gauge don't agree and are rather inaccurate. However, they are fairly consistent, so I just calibrated the readings and scribbled a calibration chart. After that, frame and floor pumps seem so uncivilized. At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. I've always believed that a "good pump" was one with which one could inflate the desired tire to the desired pressure :-) -- Cheers, John B. |
Let the Laughing Begin
On Wed, 06 Sep 2017 13:30:25 +0700, John B.
wrote: On Tue, 05 Sep 2017 09:52:07 -0700, Jeff Liebermann wrote: At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. I've always believed that a "good pump" was one with which one could inflate the desired tire to the desired pressure :-) Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? What works well for a road bicycle, might not be so good inflating an automobile tire. What works in the shop, may not be so good during a ride. Of course, there are specialized bicycle pumps optimized for these and other purposes and conditions. My idea of a "good pump" is one that will do an adequate job of inflating everything from a high pressure racing tire (multistage pump), to an air mattress (large volume piston or vane pump). It might look a bit weird, have capabilities I might rarely use, probably expensive, but will work for anything that needs inflation. Here's one application for an air pump with which I'm currently working: https://www.amazon.com/Carburetor-detector-Replaces-Tillotson-243-504/dp/B06Y542R9S Yes, it's an air pump. It's used to apply pressure to the carburetor fuel inlet on a 2 stroke engine (chain saw) to determine if the needle valve is working properly and not leaking. Apply pressure and it should open the needle valve at about 15 psi. Let it bleed down, and it should close again at 5 psi. Pressurized to 10 psi and dunk the carburetor into a bowl of water while looking for leaks (air bubbles). A "good pump" should be able to do this as well. The problem here is that this is what I want, not what the GUM (great unwashed masses) are will to buy. That makes it a "good pump" but only for me. You may have other ideas. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Let the Laughing Begin
On Tuesday, September 5, 2017 at 9:52:10 AM UTC-7, Jeff Liebermann wrote:
On Tue, 5 Sep 2017 07:04:03 -0700 (PDT), wrote: On Monday, September 4, 2017 at 9:25:51 PM UTC-7, Jeff Liebermann wrote: On Mon, 4 Sep 2017 14:01:39 -0700 (PDT), wrote: The professional is the one that's accurate and the cheaper one that was both showing the wrong pressure and probably letting pressure bleed off through the cheaper filler nozzle. Here's my bicycle pump tester: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/Bicycle%20pump%20pressure%20gauge.html I scribbled a little about how it's used in a previous postings: https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/CoySfXtGAQAJ https://groups.google.com/d/msg/rec.bicycles.tech/YsqvNggfDDM/XeXJLe5kAQAJ For a leakdown test, I attach a small pressure vessel to one port, and pump up the pressure with a bicycle pump attached to the other port. Then, I watch the pump gauge to see if it remains stable. If the test gauge leaks, I paint the plumbing with bubble mix looking for the source of the air leaks. If the gauge itself is suspect, I take it apart and check the mechanism for leaks. Well, that certainly seems a better method than getting a good pump to begin with. Quantity is my substitute for quality. When I tested my collection of floor and frame pumps, I found a few defective pumps and a few inaccurate gauges. I don't recall the numbers, but one gauge read 8 lbs low for a 60 lb tire pressure. Cleaning the crud out of the mechanism most fixed that. I don't think I own anything that might resemble a "good pump". This was from 3 years ago: http://802.11junk.com/jeffl/pics/bicycles/misc/slides/bicycle-pumps.html I now have about twice as many frame pumps. I also have 4 working floor pumps, 2 sick floor pumps, 1 worthless foot pump, and maybe a dozen assorted pencil, analog, and digital gauges. The various cheap automotive type digital gauges seem to be the most consistent and accurate, but also have mechanical problem, such as fitting only Schrader valves or a leaky fit. Maybe, some day I'll buy a "good pump" and recycle all the junk pumps. A proper dead weight pressure gauge tester/calibrator is not in my budget (although I could probably build one). Incidentally, when I go for rides these daze, I generally throw the bicycle into my Subaru and drive to where I want to ride. Before leaving, I usually top off my leaky tires with some air from a cheap 12V automotive air tire pump. The one I have has an automatic shutoff when it reaches a set pressure. I just set the dial, start the air compressor, and I'm ready to ride when it's done. The problem is that it's horribly inaccurate. The dial settings and built in pressure gauge don't agree and are rather inaccurate. However, they are fairly consistent, so I just calibrated the readings and scribbled a calibration chart. After that, frame and floor pumps seem so uncivilized. At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 Well, fortunately for us all, the exact pressure that yer tires are at is simply not that problematic. It is simply not like saddle height. If my roadbike tires are at 120 one day and 115 the next and 110 the next, well that's just okay. Below 110 I'll notice and think they feel a little soft and slow. On the mtn bike, I'll pump them up to 55-60, usually, and if they're at 50 or even 45 one day well I'll have a little softer ride that day and yea I'll work just a bit harder uphill, then get a just a bit better grip on the way back down. |
Let the Laughing Begin
Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? |
Let the Laughing Begin
On Wednesday, September 6, 2017 at 8:54:56 AM UTC-7, Jeff Liebermann wrote:
On Wed, 06 Sep 2017 13:30:25 +0700, John B. wrote: On Tue, 05 Sep 2017 09:52:07 -0700, Jeff Liebermann wrote: At one time, I proposed a portable bicycle tire inflator consisting of something like the automotive automatic shutoff compressor that I'm using, with an added LiIon rechargeable battery. Or maybe powered instead by a model airplane gasoline engine. I think I can make it small enough to be fairly flat and pocket size. A little marketing research indicated that nobody I asked would pay money for such a thing but might consider building one from a kit. Very strange but I decided that it was too risky and let the idea die a natural death. I've always believed that a "good pump" was one with which one could inflate the desired tire to the desired pressure :-) Sigh. Inflate the desired tire at what temperature, with how much effort, how quickly, to what accuracy, how big a tire, etc? What works well for a road bicycle, might not be so good inflating an automobile tire. What works in the shop, may not be so good during a ride. Of course, there are specialized bicycle pumps optimized for these and other purposes and conditions. My idea of a "good pump" is one that will do an adequate job of inflating everything from a high pressure racing tire (multistage pump), to an air mattress (large volume piston or vane pump). It might look a bit weird, have capabilities I might rarely use, probably expensive, but will work for anything that needs inflation. Here's one application for an air pump with which I'm currently working: https://www.amazon.com/Carburetor-detector-Replaces-Tillotson-243-504/dp/B06Y542R9S Yes, it's an air pump. It's used to apply pressure to the carburetor fuel inlet on a 2 stroke engine (chain saw) to determine if the needle valve is working properly and not leaking. Apply pressure and it should open the needle valve at about 15 psi. Let it bleed down, and it should close again at 5 psi. Pressurized to 10 psi and dunk the carburetor into a bowl of water while looking for leaks (air bubbles). A "good pump" should be able to do this as well. The problem here is that this is what I want, not what the GUM (great unwashed masses) are will to buy. That makes it a "good pump" but only for me. You may have other ideas. Absolutely Jeff. MTB tires will not inflate well on my Silca Pro road bike pump. It takes 25 pumps to inflate a 23 to 110. MTB's definitely need a much higher volume pump and they don't need to get above 80 psi at the highest. |
Let the Laughing Begin
On Wed, 6 Sep 2017 11:02:12 -0700 (PDT), Doug Landau
wrote: Quantity is my substitute for quality. So, to know the exact pressure at which his tires are inflated, Tom should own a dozen guages, apply them all, and average the results? Sure. The errors tend to random, some high, some low, some large, some small, etc. When a large number of measurements are averaged, the result tends to be fairly close to reality. At least that's what some climate researchers claimed when they averaged the results of many prehistoric temperature and CO2 proxies, each of which were suspected of being inaccurate, and produced an average which the was declared accurate. Actually, it would be more interesting if we took pressure readings at various times of the day. If you set your tire pressure to some number on a cold morning, and then go for a ride in the hot sun, your tire pressure will increase. Strictly speaking, one needs to be seated on the bicycle in order to get an accurate measurement or proper setting. That might be a bit awkward unless you're a contortionist. It might be instructive (and amusing) to attach a BlueGoof wireless tire pressure gauge and data logger to a wheel and watch the variations in pressure as the bicycle bounces down the road or does aerobatics. I suspect that you'll find large variations, which should make you wonder why anyone bothers to set the tire pressure more accurately than hard, firm, mush, soft, and flat. Math, numbers, formulas, and calculations: http://www.velonews.com/2017/03/bikes-and-tech/technical-faq-science-tire-pressure-rim-width-heat-buildup_433214 Math hates me. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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