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#61
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Steel is Real and Carbon is Lighter
On Wednesday, June 19, 2019 at 11:18:52 AM UTC-7, Frank Krygowski wrote:
On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. |
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#62
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Steel is Real and Carbon is Lighter
On 6/19/2019 4:52 PM, Sir Ridesalot wrote:
On Wednesday, June 19, 2019 at 2:18:52 PM UTC-4, Frank Krygowski wrote: On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. What is a "tiny improvement"? The frame on my Emonda probably weighs less than the Columbus steel forks off my last custom racing bike. Those things were suitable for clubbing baby harp seals or home defense. Weight and stiffness do matter when climbing. If we're talking about aero bits, that's harder call -- except that dopes on aero bars riding in packs can result in a massive worsening of your riding experience. Wearing aero shoe covers may keep your feet warmer on chilly mornings, which might make you faster. It all adds up. Stiffness probably does not make a detectable difference, unless the frame is so flexible that things are scraping. Remember the discussion we had about the bike magazine's test of modern stiff CF frames vs. older, heavier steel frames? The test riders gushed about how the stiffness improved their climbing, but the math showed the speed difference was precisely what would be predicted by the weight difference. Weight matters when climbing. If getting to the top of the hill before your buddy is really, really important, a lighter bike will help by whatever the percent difference in total bike+rider weight. If a 160 pound rider changes his 20 pound bike for an 18 pound bike, he should be about 1% faster up a steep hill. Whoopee! Make that a 5lb weight difference. You need to borrow a well-fitting modern 15lb racing bike with an appropriate gear range and then do a long ride with lots of hills. It's not a subtle or imagined difference compared to a T1000 or old-school steel sport touring bike, particularly if you're trying to keep up with others. Again, I'm not saying the weight doesn't make a difference! The difference it makes on an uphill is the percentage difference in bike+rider weight. Does nobody remember the discussion a couple years ago where the magazine article's data proved that? They put young racers on modern CF bikes, then on 1980s steel racing bikes and timed them up long hills. The speed difference was exactly what the weight difference predicted. Think about changing to a bike that was five pounds lighter, but then strapped a five pound weight around your waist. Hopefully people here wouldn't think you'd still be way faster up the hills, right? And again, the stiffness, the snappiness, the magical handling of a CF bike made no difference at all in that comparison test. There were other details the youngsters liked on the new bikes - as in "I was afraid to take my hands off the hoods to shift" - but the speed difference was apparently due to the weight. If others think there's some other energy savings or power increase, please explain it in engineering or scientific terms. Explain how it's not magic. -- - Frank Krygowski Weight doesn't make a difference? News to me. In 1984 I bought a MIELE BETA bicycle with Tange double-butted tubing and with a complete Shimano 600 groupset. A year or two later I bought a MIELE EQUIPE PRO with a Columbus SL frameset and with a complete Dura Ace groupset. Compared to the Beta the Equipe Pro climbed like a homesick angel, accelerated easier and in general took less energy to keep moving. I imagine that the difference a five to ten pounds lighter carbon fiber bicycle would be even more noticeable. Sir, please read more carefully. Here's what I typed above: "I'm not saying weight does not make a difference!" What I'm doing is quantifying the difference. The math isn't hard. -- - Frank Krygowski |
#63
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Steel is Real and Carbon is Lighter
On 6/19/2019 7:45 PM, jbeattie wrote:
On Wednesday, June 19, 2019 at 11:18:52 AM UTC-7, Frank Krygowski wrote: On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. What is a "tiny improvement"? The frame on my Emonda probably weighs less than the Columbus steel forks off my last custom racing bike. Those things were suitable for clubbing baby harp seals or home defense. Weight and stiffness do matter when climbing. If we're talking about aero bits, that's harder call -- except that dopes on aero bars riding in packs can result in a massive worsening of your riding experience. Wearing aero shoe covers may keep your feet warmer on chilly mornings, which might make you faster. It all adds up. Stiffness probably does not make a detectable difference, unless the frame is so flexible that things are scraping. Remember the discussion we had about the bike magazine's test of modern stiff CF frames vs. older, heavier steel frames? The test riders gushed about how the stiffness improved their climbing, but the math showed the speed difference was precisely what would be predicted by the weight difference. Weight matters when climbing. If getting to the top of the hill before your buddy is really, really important, a lighter bike will help by whatever the percent difference in total bike+rider weight. If a 160 pound rider changes his 20 pound bike for an 18 pound bike, he should be about 1% faster up a steep hill. Whoopee! Make that a 5lb weight difference. You need to borrow a well-fitting modern 15lb racing bike with an appropriate gear range and then do a long ride with lots of hills. It's not a subtle or imagined difference compared to a T1000 or old-school steel sport touring bike, particularly if you're trying to keep up with others. Again, I'm not saying the weight doesn't make a difference! The difference it makes on an uphill is the percentage difference in bike+rider weight. Does nobody remember the discussion a couple years ago where the magazine article's data proved that? They put young racers on modern CF bikes, then on 1980s steel racing bikes and timed them up long hills. The speed difference was exactly what the weight difference predicted. Think about changing to a bike that was five pounds lighter, but then strapped a five pound weight around your waist. Hopefully people here wouldn't think you'd still be way faster up the hills, right? And again, the stiffness, the snappiness, the magical handling of a CF bike made no difference at all in that comparison test. There were other details the youngsters liked on the new bikes - as in "I was afraid to take my hands off the hoods to shift" - but the speed difference was apparently due to the weight. If others think there's some other energy savings or power increase, please explain it in engineering or scientific terms. Explain how it's not magic. Well, go to all the reviews of retro bikes on GCN. E.g. https://www.youtube.com/watch?v=V4JAvQCp8ww Again, go borrow a 15lb modern racing bike that fits, then do hill repeats. Now do that on a Biketown bike. Really, there is no difference! It's all placebo effect! Now do it on a Surly Moonlander. No difference! At what point would you agree there is a difference -- and why that point? Even without almighty "data" (presumably something created by a machine and not anecdotal reports), most of us would agree that some bikes are dogs and others aren't. Geez, guys, you're very diligent about confusing yourselves! As I told Sir, I'm _not_ saying weight doesn't make a difference! I'm quantifying that difference. Didn't we all meet guys in the 1970s who thought "My new bike has six cogs instead of five, so it's going to be 20% faster"? Don't we still meet guys who think 11 cogs will be 10% faster than ten cogs? But that's silly and very unscientific. It shows a poor grasp of basic physics In the same way, there seem to be people who think "My old bike weighed 20 pounds but my new bike is 18 pounds. It's going to be 10% faster up a hill." Sorry! What matters is total weight, bike+rider. a 160 pound guy who goes from a 20 pound bike to an 18 pound bike has lost 2 out of 180 pounds. He's improved the total weight by about 1%. Will it make a difference? Yes, a difference of about 1%. So weight _does_ matter - that much. "Oh, but try a bike that's FIVE pounds lighter!!" OK, that one will be 2.8% better. It won't be 25% better. If 1% or 2.8% is worth it to you, fine. It is to some people. Other people may have a different view. BTW, the first national bike convention we ever attended was 1978 in Michigan. Since we lived in an area where we knew only one other avid cyclist, I was fascinated by all the beautiful high-end bikes. But one weird one was a guy on a super light custom frame, with the highest end and lightest SunTour components, many of which he had drilled holes in. Super light rims with tubular tires, too. He was just in awe of his own bike, telling people over and over how little it weighed (somewhere under 20 pounds). Then the big mass start parade into town started. I watched carefully as he started out, because I wanted proof it would support him. I guessed he weighted somewhere around 300 pounds, and very little of it was muscle. -- - Frank Krygowski |
#65
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Steel is Real and Carbon is Lighter
On Wed, 19 Jun 2019 20:15:30 -0400, Frank Krygowski
wrote: On 6/19/2019 4:52 PM, Sir Ridesalot wrote: On Wednesday, June 19, 2019 at 2:18:52 PM UTC-4, Frank Krygowski wrote: On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. What is a "tiny improvement"? The frame on my Emonda probably weighs less than the Columbus steel forks off my last custom racing bike. Those things were suitable for clubbing baby harp seals or home defense. Weight and stiffness do matter when climbing. If we're talking about aero bits, that's harder call -- except that dopes on aero bars riding in packs can result in a massive worsening of your riding experience. Wearing aero shoe covers may keep your feet warmer on chilly mornings, which might make you faster. It all adds up. Stiffness probably does not make a detectable difference, unless the frame is so flexible that things are scraping. Remember the discussion we had about the bike magazine's test of modern stiff CF frames vs. older, heavier steel frames? The test riders gushed about how the stiffness improved their climbing, but the math showed the speed difference was precisely what would be predicted by the weight difference. Weight matters when climbing. If getting to the top of the hill before your buddy is really, really important, a lighter bike will help by whatever the percent difference in total bike+rider weight. If a 160 pound rider changes his 20 pound bike for an 18 pound bike, he should be about 1% faster up a steep hill. Whoopee! Make that a 5lb weight difference. You need to borrow a well-fitting modern 15lb racing bike with an appropriate gear range and then do a long ride with lots of hills. It's not a subtle or imagined difference compared to a T1000 or old-school steel sport touring bike, particularly if you're trying to keep up with others. Again, I'm not saying the weight doesn't make a difference! The difference it makes on an uphill is the percentage difference in bike+rider weight. Does nobody remember the discussion a couple years ago where the magazine article's data proved that? They put young racers on modern CF bikes, then on 1980s steel racing bikes and timed them up long hills. The speed difference was exactly what the weight difference predicted. Think about changing to a bike that was five pounds lighter, but then strapped a five pound weight around your waist. Hopefully people here wouldn't think you'd still be way faster up the hills, right? And again, the stiffness, the snappiness, the magical handling of a CF bike made no difference at all in that comparison test. There were other details the youngsters liked on the new bikes - as in "I was afraid to take my hands off the hoods to shift" - but the speed difference was apparently due to the weight. If others think there's some other energy savings or power increase, please explain it in engineering or scientific terms. Explain how it's not magic. -- - Frank Krygowski Weight doesn't make a difference? News to me. In 1984 I bought a MIELE BETA bicycle with Tange double-butted tubing and with a complete Shimano 600 groupset. A year or two later I bought a MIELE EQUIPE PRO with a Columbus SL frameset and with a complete Dura Ace groupset. Compared to the Beta the Equipe Pro climbed like a homesick angel, accelerated easier and in general took less energy to keep moving. I imagine that the difference a five to ten pounds lighter carbon fiber bicycle would be even more noticeable. Sir, please read more carefully. Here's what I typed above: "I'm not saying weight does not make a difference!" What I'm doing is quantifying the difference. The math isn't hard. I recently came across a "Bicycle Calculator" http://bikecalculator.com/wattsUS.html and tried a comparison of a 150 lb rider on a 22 lb bicycle versus a 150 lb rider on a 44 lb bicycle over a 20 mile distance with zero elevation change. The 22 lb bike rider produced 100 watts of power and required 80 minutes and burned 459 kcalories. the 44 lb rider developed 103 watts of power, required 80 minutes and burned 474 kcalories. An increase of 3% in energy expended requirement for doubling the weight of the bike. I than tried it the other way with a bike half the weight of the 22lb bike and the power requirement dropped to 90 watts and 451 kcalories expended. Or a drop in energy expended of 1.7% One could argue that using watts to measure the difference showed a reduction of 10% reduction in power required but I suggest that isn't an accurate picture of what actually is happening unless one is capable of riding 20 miles and never deviating from a an exact and constant 90 watts output. I believe that energy expended (kcalories) over time is a far more accurate demonstration of the effects, if any, of a change in bicycle weight. -- Cheers, John B. |
#66
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Steel is Real and Carbon is Lighter
On Wednesday, June 19, 2019 at 8:32:05 PM UTC-4, Frank Krygowski wrote:
On 6/19/2019 7:45 PM, jbeattie wrote: On Wednesday, June 19, 2019 at 11:18:52 AM UTC-7, Frank Krygowski wrote: On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. What is a "tiny improvement"? The frame on my Emonda probably weighs less than the Columbus steel forks off my last custom racing bike. Those things were suitable for clubbing baby harp seals or home defense. Weight and stiffness do matter when climbing. If we're talking about aero bits, that's harder call -- except that dopes on aero bars riding in packs can result in a massive worsening of your riding experience. Wearing aero shoe covers may keep your feet warmer on chilly mornings, which might make you faster. It all adds up. Stiffness probably does not make a detectable difference, unless the frame is so flexible that things are scraping. Remember the discussion we had about the bike magazine's test of modern stiff CF frames vs. older, heavier steel frames? The test riders gushed about how the stiffness improved their climbing, but the math showed the speed difference was precisely what would be predicted by the weight difference. Weight matters when climbing. If getting to the top of the hill before your buddy is really, really important, a lighter bike will help by whatever the percent difference in total bike+rider weight. If a 160 pound rider changes his 20 pound bike for an 18 pound bike, he should be about 1% faster up a steep hill. Whoopee! Make that a 5lb weight difference. You need to borrow a well-fitting modern 15lb racing bike with an appropriate gear range and then do a long ride with lots of hills. It's not a subtle or imagined difference compared to a T1000 or old-school steel sport touring bike, particularly if you're trying to keep up with others. Again, I'm not saying the weight doesn't make a difference! The difference it makes on an uphill is the percentage difference in bike+rider weight. Does nobody remember the discussion a couple years ago where the magazine article's data proved that? They put young racers on modern CF bikes, then on 1980s steel racing bikes and timed them up long hills. The speed difference was exactly what the weight difference predicted. Think about changing to a bike that was five pounds lighter, but then strapped a five pound weight around your waist. Hopefully people here wouldn't think you'd still be way faster up the hills, right? And again, the stiffness, the snappiness, the magical handling of a CF bike made no difference at all in that comparison test. There were other details the youngsters liked on the new bikes - as in "I was afraid to take my hands off the hoods to shift" - but the speed difference was apparently due to the weight. If others think there's some other energy savings or power increase, please explain it in engineering or scientific terms. Explain how it's not magic. Well, go to all the reviews of retro bikes on GCN. E.g. https://www.youtube.com/watch?v=V4JAvQCp8ww Again, go borrow a 15lb modern racing bike that fits, then do hill repeats. Now do that on a Biketown bike. Really, there is no difference! It's all placebo effect! Now do it on a Surly Moonlander. No difference! At what point would you agree there is a difference -- and why that point? Even without almighty "data" (presumably something created by a machine and not anecdotal reports), most of us would agree that some bikes are dogs and others aren't. Geez, guys, you're very diligent about confusing yourselves! As I told Sir, I'm _not_ saying weight doesn't make a difference! I'm quantifying that difference. Didn't we all meet guys in the 1970s who thought "My new bike has six cogs instead of five, so it's going to be 20% faster"? Don't we still meet guys who think 11 cogs will be 10% faster than ten cogs? But that's silly and very unscientific. It shows a poor grasp of basic physics In the same way, there seem to be people who think "My old bike weighed 20 pounds but my new bike is 18 pounds. It's going to be 10% faster up a hill." Sorry! What matters is total weight, bike+rider. a 160 pound guy who goes from a 20 pound bike to an 18 pound bike has lost 2 out of 180 pounds. He's improved the total weight by about 1%. Will it make a difference? Yes, a difference of about 1%. So weight _does_ matter - that much. "Oh, but try a bike that's FIVE pounds lighter!!" OK, that one will be 2.8% better. It won't be 25% better. If 1% or 2.8% is worth it to you, fine. It is to some people. Other people may have a different view. BTW, the first national bike convention we ever attended was 1978 in Michigan. Since we lived in an area where we knew only one other avid cyclist, I was fascinated by all the beautiful high-end bikes. But one weird one was a guy on a super light custom frame, with the highest end and lightest SunTour components, many of which he had drilled holes in. Super light rims with tubular tires, too. He was just in awe of his own bike, telling people over and over how little it weighed (somewhere under 20 pounds). Then the big mass start parade into town started. I watched carefully as he started out, because I wanted proof it would support him. I guessed he weighted somewhere around 300 pounds, and very little of it was muscle.. -- - Frank Krygowski The lighter weight and more cogs with the same or very similar high and low gears means there's less of a jump between each cog. Therefore an 11 cogs cogset would be more efficient than a 7 cogs cogset because the rider won't spin out when changing gears or have to pedal harder than he/she would if the jumps between gears were larger. I've even built up a 9 cogs corncob 11-19 teeth cogset for my skinny tire drop-bar MTB because the small incremental jumps between gears makes riding the rolling hills around here more efficient and thus more enjoyable. Once again your mileage varies and so does your needs and/or wants but that doesn't mean that those who have and enjoy riding a very lightweight bicycle with 11 or even m ore cogs is wrong to do so. It's different strokes for different folks. Oh, another thing. I have another bicycle with 9 cogs on it. I have it set up with 7 fairly close cogs and 2 bailout/wind/steep hills cogs. It gives me the best of a 7 cogs setup plus those two bailout gears. Cheers |
#67
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Steel is Real and Carbon is Lighter
On 20/06/2019 01.32, AMuzi wrote:
On 6/19/2019 5:10 PM, wrote: On Wednesday, June 19, 2019 at 3:27:59 PM UTC-5, sms wrote: But it isn't just weight. There is a significant performance difference between a well-made steel racing frame and a carbon-fiber frame. Please give some factual, objective reasons for this mythical "significant performance difference" you cite.Â* Other than frame/fork weight.Â* Carbon will most likely be lighter in weight than a steel bicycle.Â* And weight can make a difference in acceleration and climbing speed.Â* Now I will give you the fact the fastest bicycle in the world (183.9mph) does appear to be a carbon KHS frame with a motorcycle shock fork on the front. https://www.bicycling.com/news/a2328...-speed-record/ The steel frame handles and corners better and of course will last much longer. The lower weight of the carbon-fiber frame, as well as all the other carbon-fiber pieces, is the appeal to racers of carbon. Yes the generally lighter weight of carbon over steel is appealing to racers.Â* But why do you think steel handles and corners better than carbon?Â* Seems to me if all the frames are made with the same angles and lengths, handling should be equal regardless of weight.Â* What magical property is in steel that allows it to stick to the road better than carbon?Â* Lean more in turns.Â* Make tighter turns.Â* Float over the road surface? And why do you think steel "will last much longer"?Â* Steel can rust. Carbon doesn't.Â* Steel bicycle tubes are very thin.Â* Easy to dent and crumple.Â* Carbon frame tubes probably thicker.Â* I have a broken steel Don Walker bicycle frame hanging in my garage.Â* He makes VERY high end custom steel frames.Â* Yet it broke. https://www.donwalkercycles.com/ Your overview is generally right but carbon has its own failure modes, not to be overlooked. This was my thought. You take steel, aluminum, titanium or carbon, pair the weight down to the minimum, and they will all fail one way or another. Also, the ride will be different. It really depends on what you want, and what you want to sacrifice. I'm a commuter, a decent, lightish, steel frame is the way to go, I'm not going to be commuting with me, the fat, the rack and mudguards on a Cannondale CAAD10. Well, I might, just not for very long. |
#68
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Steel is Real and Carbon is Lighter
Sir Ridesalot wrote:
On Wednesday, June 19, 2019 at 8:32:05 PM UTC-4, Frank Krygowski wrote: On 6/19/2019 7:45 PM, jbeattie wrote: On Wednesday, June 19, 2019 at 11:18:52 AM UTC-7, Frank Krygowski wrote: On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. What is a "tiny improvement"? The frame on my Emonda probably weighs less than the Columbus steel forks off my last custom racing bike. Those things were suitable for clubbing baby harp seals or home defense. Weight and stiffness do matter when climbing. If we're talking about aero bits, that's harder call -- except that dopes on aero bars riding in packs can result in a massive worsening of your riding experience. Wearing aero shoe covers may keep your feet warmer on chilly mornings, which might make you faster. It all adds up. Stiffness probably does not make a detectable difference, unless the frame is so flexible that things are scraping. Remember the discussion we had about the bike magazine's test of modern stiff CF frames vs. older, heavier steel frames? The test riders gushed about how the stiffness improved their climbing, but the math showed the speed difference was precisely what would be predicted by the weight difference. Weight matters when climbing. If getting to the top of the hill before your buddy is really, really important, a lighter bike will help by whatever the percent difference in total bike+rider weight. If a 160 pound rider changes his 20 pound bike for an 18 pound bike, he should be about 1% faster up a steep hill. Whoopee! Make that a 5lb weight difference. You need to borrow a well-fitting modern 15lb racing bike with an appropriate gear range and then do a long ride with lots of hills. It's not a subtle or imagined difference compared to a T1000 or old-school steel sport touring bike, particularly if you're trying to keep up with others. Again, I'm not saying the weight doesn't make a difference! The difference it makes on an uphill is the percentage difference in bike+rider weight. Does nobody remember the discussion a couple years ago where the magazine article's data proved that? They put young racers on modern CF bikes, then on 1980s steel racing bikes and timed them up long hills. The speed difference was exactly what the weight difference predicted. Think about changing to a bike that was five pounds lighter, but then strapped a five pound weight around your waist. Hopefully people here wouldn't think you'd still be way faster up the hills, right? And again, the stiffness, the snappiness, the magical handling of a CF bike made no difference at all in that comparison test. There were other details the youngsters liked on the new bikes - as in "I was afraid to take my hands off the hoods to shift" - but the speed difference was apparently due to the weight. If others think there's some other energy savings or power increase, please explain it in engineering or scientific terms. Explain how it's not magic. Well, go to all the reviews of retro bikes on GCN. E.g. https://www.youtube.com/watch?v=V4JAvQCp8ww Again, go borrow a 15lb modern racing bike that fits, then do hill repeats. Now do that on a Biketown bike. Really, there is no difference! It's all placebo effect! Now do it on a Surly Moonlander. No difference! At what point would you agree there is a difference -- and why that point? Even without almighty "data" (presumably something created by a machine and not anecdotal reports), most of us would agree that some bikes are dogs and others aren't. Geez, guys, you're very diligent about confusing yourselves! As I told Sir, I'm _not_ saying weight doesn't make a difference! I'm quantifying that difference. Didn't we all meet guys in the 1970s who thought "My new bike has six cogs instead of five, so it's going to be 20% faster"? Don't we still meet guys who think 11 cogs will be 10% faster than ten cogs? But that's silly and very unscientific. It shows a poor grasp of basic physics In the same way, there seem to be people who think "My old bike weighed 20 pounds but my new bike is 18 pounds. It's going to be 10% faster up a hill." Sorry! What matters is total weight, bike+rider. a 160 pound guy who goes from a 20 pound bike to an 18 pound bike has lost 2 out of 180 pounds. He's improved the total weight by about 1%. Will it make a difference? Yes, a difference of about 1%. So weight _does_ matter - that much. "Oh, but try a bike that's FIVE pounds lighter!!" OK, that one will be 2.8% better. It won't be 25% better. If 1% or 2.8% is worth it to you, fine. It is to some people. Other people may have a different view. BTW, the first national bike convention we ever attended was 1978 in Michigan. Since we lived in an area where we knew only one other avid cyclist, I was fascinated by all the beautiful high-end bikes. But one weird one was a guy on a super light custom frame, with the highest end and lightest SunTour components, many of which he had drilled holes in. Super light rims with tubular tires, too. He was just in awe of his own bike, telling people over and over how little it weighed (somewhere under 20 pounds). Then the big mass start parade into town started. I watched carefully as he started out, because I wanted proof it would support him. I guessed he weighted somewhere around 300 pounds, and very little of it was muscle. -- - Frank Krygowski The lighter weight and more cogs with the same or very similar high and low gears means there's less of a jump between each cog. Therefore an 11 cogs cogset would be more efficient than a 7 cogs cogset because the rider won't spin out when changing gears or have to pedal harder than he/she would if the jumps between gears were larger. I've even built up a 9 cogs corncob 11-19 teeth cogset for my skinny tire drop-bar MTB because the small incremental jumps between gears makes riding the rolling hills around here more efficient and thus more enjoyable. Once again your mileage varies and so does your needs and/or wants but that doesn't mean that those who have and enjoy riding a very lightweight bicycle with 11 or even m ore cogs is wrong to do so. It's different strokes for different folks. Oh, another thing. I have another bicycle with 9 cogs on it. I have it set up with 7 fairly close cogs and 2 bailout/wind/steep hills cogs. It gives me the best of a 7 cogs setup plus those two bailout gears. Cheers I’ve never heard anyone say that 11 speed is faster than 10. More efficient, more choice, less need to switch rings, smoother transition etc. I guess in a race given a specific combination of chain rings and cassette it’s possible. -- duane |
#69
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Steel is Real and Carbon is Lighter
On 6/20/2019 5:21 AM, Duane wrote:
Sir Ridesalot wrote: On Wednesday, June 19, 2019 at 8:32:05 PM UTC-4, Frank Krygowski wrote: On 6/19/2019 7:45 PM, jbeattie wrote: On Wednesday, June 19, 2019 at 11:18:52 AM UTC-7, Frank Krygowski wrote: On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. What is a "tiny improvement"? The frame on my Emonda probably weighs less than the Columbus steel forks off my last custom racing bike. Those things were suitable for clubbing baby harp seals or home defense. Weight and stiffness do matter when climbing. If we're talking about aero bits, that's harder call -- except that dopes on aero bars riding in packs can result in a massive worsening of your riding experience. Wearing aero shoe covers may keep your feet warmer on chilly mornings, which might make you faster. It all adds up. Stiffness probably does not make a detectable difference, unless the frame is so flexible that things are scraping. Remember the discussion we had about the bike magazine's test of modern stiff CF frames vs. older, heavier steel frames? The test riders gushed about how the stiffness improved their climbing, but the math showed the speed difference was precisely what would be predicted by the weight difference. Weight matters when climbing. If getting to the top of the hill before your buddy is really, really important, a lighter bike will help by whatever the percent difference in total bike+rider weight. If a 160 pound rider changes his 20 pound bike for an 18 pound bike, he should be about 1% faster up a steep hill. Whoopee! Make that a 5lb weight difference. You need to borrow a well-fitting modern 15lb racing bike with an appropriate gear range and then do a long ride with lots of hills. It's not a subtle or imagined difference compared to a T1000 or old-school steel sport touring bike, particularly if you're trying to keep up with others. Again, I'm not saying the weight doesn't make a difference! The difference it makes on an uphill is the percentage difference in bike+rider weight. Does nobody remember the discussion a couple years ago where the magazine article's data proved that? They put young racers on modern CF bikes, then on 1980s steel racing bikes and timed them up long hills. The speed difference was exactly what the weight difference predicted. Think about changing to a bike that was five pounds lighter, but then strapped a five pound weight around your waist. Hopefully people here wouldn't think you'd still be way faster up the hills, right? And again, the stiffness, the snappiness, the magical handling of a CF bike made no difference at all in that comparison test. There were other details the youngsters liked on the new bikes - as in "I was afraid to take my hands off the hoods to shift" - but the speed difference was apparently due to the weight. If others think there's some other energy savings or power increase, please explain it in engineering or scientific terms. Explain how it's not magic. Well, go to all the reviews of retro bikes on GCN. E.g. https://www.youtube.com/watch?v=V4JAvQCp8ww Again, go borrow a 15lb modern racing bike that fits, then do hill repeats. Now do that on a Biketown bike. Really, there is no difference! It's all placebo effect! Now do it on a Surly Moonlander. No difference! At what point would you agree there is a difference -- and why that point? Even without almighty "data" (presumably something created by a machine and not anecdotal reports), most of us would agree that some bikes are dogs and others aren't. Geez, guys, you're very diligent about confusing yourselves! As I told Sir, I'm _not_ saying weight doesn't make a difference! I'm quantifying that difference. Didn't we all meet guys in the 1970s who thought "My new bike has six cogs instead of five, so it's going to be 20% faster"? Don't we still meet guys who think 11 cogs will be 10% faster than ten cogs? But that's silly and very unscientific. It shows a poor grasp of basic physics In the same way, there seem to be people who think "My old bike weighed 20 pounds but my new bike is 18 pounds. It's going to be 10% faster up a hill." Sorry! What matters is total weight, bike+rider. a 160 pound guy who goes from a 20 pound bike to an 18 pound bike has lost 2 out of 180 pounds. He's improved the total weight by about 1%. Will it make a difference? Yes, a difference of about 1%. So weight _does_ matter - that much. "Oh, but try a bike that's FIVE pounds lighter!!" OK, that one will be 2.8% better. It won't be 25% better. If 1% or 2.8% is worth it to you, fine. It is to some people. Other people may have a different view. BTW, the first national bike convention we ever attended was 1978 in Michigan. Since we lived in an area where we knew only one other avid cyclist, I was fascinated by all the beautiful high-end bikes. But one weird one was a guy on a super light custom frame, with the highest end and lightest SunTour components, many of which he had drilled holes in. Super light rims with tubular tires, too. He was just in awe of his own bike, telling people over and over how little it weighed (somewhere under 20 pounds). Then the big mass start parade into town started. I watched carefully as he started out, because I wanted proof it would support him. I guessed he weighted somewhere around 300 pounds, and very little of it was muscle. -- - Frank Krygowski The lighter weight and more cogs with the same or very similar high and low gears means there's less of a jump between each cog. Therefore an 11 cogs cogset would be more efficient than a 7 cogs cogset because the rider won't spin out when changing gears or have to pedal harder than he/she would if the jumps between gears were larger. I've even built up a 9 cogs corncob 11-19 teeth cogset for my skinny tire drop-bar MTB because the small incremental jumps between gears makes riding the rolling hills around here more efficient and thus more enjoyable. Once again your mileage varies and so does your needs and/or wants but that doesn't mean that those who have and enjoy riding a very lightweight bicycle with 11 or even m ore cogs is wrong to do so. It's different strokes for different folks. Oh, another thing. I have another bicycle with 9 cogs on it. I have it set up with 7 fairly close cogs and 2 bailout/wind/steep hills cogs. It gives me the best of a 7 cogs setup plus those two bailout gears. Cheers I’ve never heard anyone say that 11 speed is faster than 10. More efficient, more choice, less need to switch rings, smoother transition etc. I guess in a race given a specific combination of chain rings and cassette it’s possible. Indeed. Even for me having an 18 & a 19 is a big feature not reasonable to a 4 speed or five speed freewheel. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
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Steel is Real and Carbon is Lighter
On Wednesday, June 19, 2019 at 5:32:05 PM UTC-7, Frank Krygowski wrote:
On 6/19/2019 7:45 PM, jbeattie wrote: On Wednesday, June 19, 2019 at 11:18:52 AM UTC-7, Frank Krygowski wrote: On 6/19/2019 10:25 AM, jbeattie wrote: On Tuesday, June 18, 2019 at 8:06:37 PM UTC-7, Frank Krygowski wrote: On 6/18/2019 1:24 PM, jbeattie wrote: On Tuesday, June 18, 2019 at 9:49:50 AM UTC-7, Frank Krygowski wrote: For ordinary riding? No, most tiny improvements make no noticeable difference. Even though we all know the near-magic power of red paint. What is a "tiny improvement"? The frame on my Emonda probably weighs less than the Columbus steel forks off my last custom racing bike. Those things were suitable for clubbing baby harp seals or home defense. Weight and stiffness do matter when climbing. If we're talking about aero bits, that's harder call -- except that dopes on aero bars riding in packs can result in a massive worsening of your riding experience. Wearing aero shoe covers may keep your feet warmer on chilly mornings, which might make you faster. It all adds up. Stiffness probably does not make a detectable difference, unless the frame is so flexible that things are scraping. Remember the discussion we had about the bike magazine's test of modern stiff CF frames vs. older, heavier steel frames? The test riders gushed about how the stiffness improved their climbing, but the math showed the speed difference was precisely what would be predicted by the weight difference. Weight matters when climbing. If getting to the top of the hill before your buddy is really, really important, a lighter bike will help by whatever the percent difference in total bike+rider weight. If a 160 pound rider changes his 20 pound bike for an 18 pound bike, he should be about 1% faster up a steep hill. Whoopee! Make that a 5lb weight difference. You need to borrow a well-fitting modern 15lb racing bike with an appropriate gear range and then do a long ride with lots of hills. It's not a subtle or imagined difference compared to a T1000 or old-school steel sport touring bike, particularly if you're trying to keep up with others. Again, I'm not saying the weight doesn't make a difference! The difference it makes on an uphill is the percentage difference in bike+rider weight. Does nobody remember the discussion a couple years ago where the magazine article's data proved that? They put young racers on modern CF bikes, then on 1980s steel racing bikes and timed them up long hills. The speed difference was exactly what the weight difference predicted. Think about changing to a bike that was five pounds lighter, but then strapped a five pound weight around your waist. Hopefully people here wouldn't think you'd still be way faster up the hills, right? And again, the stiffness, the snappiness, the magical handling of a CF bike made no difference at all in that comparison test. There were other details the youngsters liked on the new bikes - as in "I was afraid to take my hands off the hoods to shift" - but the speed difference was apparently due to the weight. If others think there's some other energy savings or power increase, please explain it in engineering or scientific terms. Explain how it's not magic. Well, go to all the reviews of retro bikes on GCN. E.g. https://www.youtube.com/watch?v=V4JAvQCp8ww Again, go borrow a 15lb modern racing bike that fits, then do hill repeats. Now do that on a Biketown bike. Really, there is no difference! It's all placebo effect! Now do it on a Surly Moonlander. No difference! At what point would you agree there is a difference -- and why that point? Even without almighty "data" (presumably something created by a machine and not anecdotal reports), most of us would agree that some bikes are dogs and others aren't. Geez, guys, you're very diligent about confusing yourselves! As I told Sir, I'm _not_ saying weight doesn't make a difference! I'm quantifying that difference. Didn't we all meet guys in the 1970s who thought "My new bike has six cogs instead of five, so it's going to be 20% faster"? Don't we still meet guys who think 11 cogs will be 10% faster than ten cogs? But that's silly and very unscientific. It shows a poor grasp of basic physics In the same way, there seem to be people who think "My old bike weighed 20 pounds but my new bike is 18 pounds. It's going to be 10% faster up a hill." Sorry! What matters is total weight, bike+rider. a 160 pound guy who goes from a 20 pound bike to an 18 pound bike has lost 2 out of 180 pounds. He's improved the total weight by about 1%. Will it make a difference? Yes, a difference of about 1%. So weight _does_ matter - that much. "Oh, but try a bike that's FIVE pounds lighter!!" OK, that one will be 2.8% better. It won't be 25% better. If 1% or 2.8% is worth it to you, fine. It is to some people. Other people may have a different view. BTW, the first national bike convention we ever attended was 1978 in Michigan. Since we lived in an area where we knew only one other avid cyclist, I was fascinated by all the beautiful high-end bikes. But one weird one was a guy on a super light custom frame, with the highest end and lightest SunTour components, many of which he had drilled holes in. Super light rims with tubular tires, too. He was just in awe of his own bike, telling people over and over how little it weighed (somewhere under 20 pounds). Then the big mass start parade into town started. I watched carefully as he started out, because I wanted proof it would support him. I guessed he weighted somewhere around 300 pounds, and very little of it was muscle.. Applying a formula and coming up with a "percentage better" based on total bicycle and rider weight is deceptive. A better paradigm is lifting weights -- moving 15 pounds uphill rather than 20. You have to determine the additional energy needed to move that weight and how the additional energy affects the rider over time. Energy needed may depend on frame flex, tires and a number of other factors that are bicycle dependent. The effect on the rider depends on many things. We are not constant speed motors. Assuming a rider is attempting to maintain the same speed on a heavier and less efficient bike, the additional effort may be enough to exhaust him or her before the top of a climb -- which turns the last miles into a creep-along. Time is not off by 2% based on some formula but is off by more -- depending on how badly he or she blows. When you run the tank out, you could end up walking the last miles or sitting under a tree and resting. -- Jay Beattie. |
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