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#131
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Creeping brake pad drag
Frank Krygowski writes:
On Sunday, November 24, 2019 at 2:00:26 PM UTC-5, Radey Shouman wrote: Frank Krygowski writes: My point was not that I would actually make one. My point was that manual (non-STI) shifting is a truly simple system. Despite your claims, Di2 is not a simple system. The complexity is hidden inside an unrepairable box that you replace if it goes bad, but the complexity is there. For either system, equally, most of the complexity is hidden in the design of the chain, and gears. The chain is unrepairable, and all of us replace it when it goes bad. When the zombie apocalypse comes, we'll ride bicycles just as long as the chain supply holds out, and no longer. Focus, please! The difference in complexity between the two systems is not the chain, the cogs or the mechanical parts of the derailleur - i.e. the parallelogram linkage and the jockey wheel setup. Those are essentially identical, whether moved by cable or Di2. Once you start riding a chain-driven, rubber tired, multi-gear bicycle, you have eaten the apple of complex, throw-away industrial products. Things that no single person knows how to make -- recall Doug Cimperman's postings here on making tires, and as I recall he was buying all the materials he practically could. Now this argument sometimes meets resistance from those unfamiliar with the engineering mode of thought, but my point is that the additional complexity, if there is any, of replacing springs and bespoke clockwork with batteries and microprocessors, is /negligible/, it is /in the noise/. No sense worrying about it at all. There are reasons to prefer older stuff, it's proven, and you know how to deal with it. I understand that attitude as an extremely late adopter myself. I buy my coffee with folding money, I heat my house with steam, I shift my bicycle using friction shifters on the downtube, I long for the world of payphones, and know of two lonely holdouts in my vicinity. I am not likely ever to have an electronically shifted bike with with hydraulic brakes, even when they're a dime a dozen on craigslist. But that's just /my/ personal preference, not some eternal verity nor engineering principle. The difference in complexity is the lever, cable and a bit of cable housing vs. some pushbuttons, an electronic actuator of some kind (probably a stepper motor) a collection of microelectronic bits and a few hundred lines of code. And as a final detail, I wasn't comparing Di2 against STI. Think barcons. If you like, make them index barcons, because the detents don't add much complexity. Finally, I'll repeat that I'm not saying Di2 doesn't work, or can't be reliable, or should be abolished. I'm saying that in my view, its benefits are not worth its detriments. What you're really saying is that it offends your esthetic sense. That's fine, /you/ don't have to use it. Bowden cables (ever tried to make one of those?) will be available for the foreseeable future. |
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#132
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Creeping brake pad drag
On Monday, November 25, 2019 at 8:02:32 AM UTC-8, Radey Shouman wrote:
Frank Krygowski writes: On Sunday, November 24, 2019 at 2:00:26 PM UTC-5, Radey Shouman wrote: Frank Krygowski writes: My point was not that I would actually make one. My point was that manual (non-STI) shifting is a truly simple system. Despite your claims, Di2 is not a simple system. The complexity is hidden inside an unrepairable box that you replace if it goes bad, but the complexity is there. For either system, equally, most of the complexity is hidden in the design of the chain, and gears. The chain is unrepairable, and all of us replace it when it goes bad. When the zombie apocalypse comes, we'll ride bicycles just as long as the chain supply holds out, and no longer. |
#133
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Creeping brake pad drag
On Monday, November 25, 2019 at 4:43:52 PM UTC+1, Sir Ridesalot wrote:
On Monday, 25 November 2019 09:27:59 UTC-5, wrote: On Monday, November 25, 2019 at 4:57:17 AM UTC+1, Frank Krygowski wrote: On 11/24/2019 8:08 PM, Sir Ridesalot wrote: So, just how much difference do those wattage differences from the video and which numbers I posted make in real life? I just ran some numbers. Lou can check me, but here's what I got. I fitted an equation to the "modern kit, modern bike" curve - the one that said 25kph takes only 79 Watts (not counting rolling resistance and drivetrain friction). The equation I got was Power = 0.0097 * speed ^ 2.7918 The "retro" bike took 87 Watts to go 25kph. So I backsolved to find out what speed the "modern" bike would go with 87 Watts. I came up with 26.05 kph. In other words, if you ditched your "retro" bike with round tubes, square section rims, old style handlebars, etc. and spent the money on a super-sleek aero modern bike, a 25kph rider would be able to go 26 kph. In miles per hour, that bike would take a 15.5 mph rider all the way up to 16.1 mph. Roughly half a mile per hour faster. I note that you get almost as much benefit switching from wrinkled wool clothing to an aero racing suit. So anyone NOT riding in a super-sleek racing suit should first buy one of those and carefully measure how much difference it makes on your normal rides. You can probably get a set of race clothes for a hundred bucks. See for yourself what that much difference feels like before you spend $2000+ on a full aero bike. -- - Frank Krygowski 1. no flappy clothes, 2. position on your bike, 3. better tires, 4. aero wheels, 5. aero bike Lou One of the tests in that video was a retro bike with modern kit/clothing and another test was with a modern bike with modern kit/clothing. Thus whatever difference there was should have been due to the differences with the bicycles alone not the rider. I do wonder now though if they used the same tires on all of the bikes? Cheers Tires didn't matter in the test. They didn't measure the rolling resistance or drive train loss. The measured the drag of the bicyle and rider wearing different clothes. Lou |
#134
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Creeping brake pad drag
On Monday, 25 November 2019 11:45:19 UTC-5, jbeattie wrote:
On Monday, November 25, 2019 at 8:02:32 AM UTC-8, Radey Shouman wrote: Frank Krygowski writes: On Sunday, November 24, 2019 at 2:00:26 PM UTC-5, Radey Shouman wrote: Frank Krygowski writes: My point was not that I would actually make one. My point was that manual (non-STI) shifting is a truly simple system. Despite your claims, Di2 is not a simple system. The complexity is hidden inside an unrepairable box that you replace if it goes bad, but the complexity is there. For either system, equally, most of the complexity is hidden in the design of the chain, and gears. The chain is unrepairable, and all of us replace it when it goes bad. When the zombie apocalypse comes, we'll ride bicycles just as long as the chain supply holds out, and no longer. Focus, please! The difference in complexity between the two systems is not the chain, the cogs or the mechanical parts of the derailleur - i.e. the parallelogram linkage and the jockey wheel setup. Those are essentially identical, whether moved by cable or Di2. Once you start riding a chain-driven, rubber tired, multi-gear bicycle, you have eaten the apple of complex, throw-away industrial products. Things that no single person knows how to make -- recall Doug Cimperman's postings here on making tires, and as I recall he was buying all the materials he practically could. Now this argument sometimes meets resistance from those unfamiliar with the engineering mode of thought, but my point is that the additional complexity, if there is any, of replacing springs and bespoke clockwork with batteries and microprocessors, is /negligible/, it is /in the noise/. No sense worrying about it at all. There are reasons to prefer older stuff, it's proven, and you know how to deal with it. I understand that attitude as an extremely late adopter myself. I buy my coffee with folding money, I heat my house with steam, I shift my bicycle using friction shifters on the downtube, I long for the world of payphones, and know of two lonely holdouts in my vicinity. Steam heat is incredibly complex compared to a simple forced-air, which is just a fan and a burner. My hydronic system looks like something out of the engine room in Das Boot -- and the piping for the steam system of my childhood was covered in asbestos and topped with JM blue mud, so I least I know which bankrupt company to sue when I get meso. And with no ductwork, you're screwed if you want AC unless you do some retrofit Unico or split system. I don't miss payphones except for finding stray coins in coin returns. As a kid, they were a gold mine -- along with that penny gum machine at the Woolworths that would keep producing balls if you twisted the handle just far enough but not too far. I also like TV remotes and not having to flip LPs, which I still do, but it is an inconvenience. Paper money doubles transaction time at most registers. I would like to get rid of tip screens, however. Why should I tip you for handing me a coffee across the counter? It's gotten ridiculous. All social media could be unplugged, IMO. If I weren't typing this post, I'd probably be doing something productive. What I don't like are the transitions between the new and the old -- first generation low volume flush toilets, fluorescent bulbs, early silica compound tires -- my leaking first generation Goretex tent. Early adopting doesn't pay. -- Jay Beattie. I remember reading many many years ago to let the racers adopt and perfect any new bicycle stuff. I could see where that could pay off in preventing a non-racing bicyclist from ending up with orphan stuff after it was produced for just a couple of years; Shimano AX stuff comes to mind as does the Suntour Sealed Rear Mountech derailleur I bought that exploded the next day when I pedaled from a stop when the derailleur was not precisely lined up with a rear cog. IIRC that derailleur was $75.00. What was maddening about it was that the failure wasn't warrantied and thus I was out the $75.00 and the derailleur. I'll let others adopt and experiment with new stuff. Cheers |
#135
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Creeping brake pad drag
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#137
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Creeping brake pad drag
On 11/25/2019 8:22 AM, AMuzi wrote:
On 11/24/2019 10:15 PM, Frank Krygowski wrote: On 11/24/2019 7:04 PM, Duane wrote: I have 11 speed SRAM and it works well.* But honestly a typical 105 setup today is light years ahead of the stuff we rode in the old days with friction shifters and toe clips.** Anyone can argue that new tech isn’t necessary. Seems silly. It probably depends on your personal definition of "necessary." For some people, biking "necessary" is the same as a teenage girl's definition when her mom takes her to the mall: "Mom, _everyone_ has that style! I've _got_ to have it! It's _necessary_!!" For me, "necessary" means something more like "I'd be unable to ride a bike without it. Or at least, riding without it would be a terrible experience." The line is very personal and dependent on taste more than engineering analysis. I'm riding around on a bog simple fixie yet you 'need' those complex gear choices. For another guy 2x12 suits his needs better than his old 3x10 for reasons you may not appreciate but they are real for him. And it depends on conditions. For my local village riding, I mostly use a Sturmey-Archer 3 speed. For most of my riding, I use bikes that have five (count 'em, five!) cogs in back. And I wouldn't want to do a loaded tour without a granny chainring. But I'd submit that the preferences for 2x12 vs. 3x10 may well be influenced by fashion and advertising. Which is actually not a total condemnation. I'm sure I've previously mentioned brain scans proving that people really did prefer the wine they _thought_ was much more expensive, even when it was the exact same wine. The advertising was false, but the pleasure was real. But this is (purportedly) a technical discussion group. Seems that discussions here should give some credit to engineering analysis. -- - Frank Krygowski |
#138
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Creeping brake pad drag
On 11/25/2019 11:45 AM, jbeattie wrote:
I don't miss payphones except for finding stray coins in coin returns. As a kid, they were a gold mine -- along with that penny gum machine at the Woolworths that would keep producing balls if you twisted the handle just far enough but not too far. I also like TV remotes and not having to flip LPs, which I still do, but it is an inconvenience. Paper money doubles transaction time at most registers. I disagree about the paper money - at least, if the customer is (even) older than I am. I've been stuck behind ladies baffled by the choice of "Debit" vs. "Credit" plus "What's a PIN number? Oh, I've got that in here somewhere..." Which is not to mention people backing up the line by trying to call up the store's app on their new phone to find the online coupon for ten cents off on Q-tips. There have been times I wished they'd brought in a dozen of their chickens' eggs to trade for their Geritol. -- - Frank Krygowski |
#139
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Creeping brake pad drag
On Monday, 25 November 2019 12:31:40 UTC-5, Frank Krygowski wrote:
On 11/25/2019 8:22 AM, AMuzi wrote: On 11/24/2019 10:15 PM, Frank Krygowski wrote: On 11/24/2019 7:04 PM, Duane wrote: I have 11 speed SRAM and it works well.Â* But honestly a typical 105 setup today is light years ahead of the stuff we rode in the old days with friction shifters and toe clips.Â*Â* Anyone can argue that new tech isn’t necessary. Seems silly. It probably depends on your personal definition of "necessary." For some people, biking "necessary" is the same as a teenage girl's definition when her mom takes her to the mall: "Mom, _everyone_ has that style! I've _got_ to have it! It's _necessary_!!" For me, "necessary" means something more like "I'd be unable to ride a bike without it. Or at least, riding without it would be a terrible experience." The line is very personal and dependent on taste more than engineering analysis. I'm riding around on a bog simple fixie yet you 'need' those complex gear choices. For another guy 2x12 suits his needs better than his old 3x10 for reasons you may not appreciate but they are real for him. And it depends on conditions. For my local village riding, I mostly use a Sturmey-Archer 3 speed. For most of my riding, I use bikes that have five (count 'em, five!) cogs in back. And I wouldn't want to do a loaded tour without a granny chainring. But I'd submit that the preferences for 2x12 vs. 3x10 may well be influenced by fashion and advertising. Which is actually not a total condemnation. I'm sure I've previously mentioned brain scans proving that people really did prefer the wine they _thought_ was much more expensive, even when it was the exact same wine. The advertising was false, but the pleasure was real. But this is (purportedly) a technical discussion group. Seems that discussions here should give some credit to engineering analysis. -- - Frank Krygowski With the number of Trolls posting here and the endless non-bicyling content I was beginning to wonder if this newsgroup was going to ever have anything bicycling related again never mind technical. At least the guys in that video appeared to be impartial with their setup and tests. Cheers |
#140
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Creeping brake pad drag
On 11/25/2019 10:43 AM, Sir Ridesalot wrote:
On Monday, 25 November 2019 09:27:59 UTC-5, wrote: On Monday, November 25, 2019 at 4:57:17 AM UTC+1, Frank Krygowski wrote: On 11/24/2019 8:08 PM, Sir Ridesalot wrote: So, just how much difference do those wattage differences from the video and which numbers I posted make in real life? I just ran some numbers. Lou can check me, but here's what I got. I fitted an equation to the "modern kit, modern bike" curve - the one that said 25kph takes only 79 Watts (not counting rolling resistance and drivetrain friction). The equation I got was Power = 0.0097 * speed ^ 2.7918 The "retro" bike took 87 Watts to go 25kph. So I backsolved to find out what speed the "modern" bike would go with 87 Watts. I came up with 26.05 kph. In other words, if you ditched your "retro" bike with round tubes, square section rims, old style handlebars, etc. and spent the money on a super-sleek aero modern bike, a 25kph rider would be able to go 26 kph. In miles per hour, that bike would take a 15.5 mph rider all the way up to 16.1 mph. Roughly half a mile per hour faster. I note that you get almost as much benefit switching from wrinkled wool clothing to an aero racing suit. So anyone NOT riding in a super-sleek racing suit should first buy one of those and carefully measure how much difference it makes on your normal rides. You can probably get a set of race clothes for a hundred bucks. See for yourself what that much difference feels like before you spend $2000+ on a full aero bike. -- - Frank Krygowski 1. no flappy clothes, 2. position on your bike, 3. better tires, 4. aero wheels, 5. aero bike Lou One of the tests in that video was a retro bike with modern kit/clothing and another test was with a modern bike with modern kit/clothing. Thus whatever difference there was should have been due to the differences with the bicycles alone not the rider. I do wonder now though if they used the same tires on all of the bikes? Cheers While your question about performance advantage is interesting, for those of us that aren't pure racers the real benefit (IMO) of a modern road bike to a "retro" bike would be more about ease of use and dependability. I'm thinking brifters over down tube friction shifters, clipless pedals over toe straps, wider range gearing, less weight to carry up hills etc. etc. etc. |
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