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#42
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New Carbon Fiber Information
On 12/01/17 03:36, wrote:
On Tuesday, January 10, 2017 at 5:59:05 PM UTC-8, James wrote: On 11/01/17 01:48, wrote: A friend who speaks Italian spoke with a bike builder in Italy who spoke to Ernesto Colnago. He verified that the problem with Carbon Fiber aside from possible manufacturing defects is that the resins grow more and more brittle with age. After two years or so they can grow so brittle that the ultra-lights can fail at any second. This is why Colnago will only give two year warranties and why they build their "light" bikes considerably heavier than other manufacturers. Have a good ride on your CF when you can get the same weight with an aluminum frame. I don't believe age is what causes embrittlement in CFRP, but exposure to UV light and contaminants that may attack the polymer probably does. James, you don't HAVE to believe it. All it means is that the curing agents in the resins have to have a fairly large amount over the ideal in order to harden in the time necessary to use on a production line. And since there is more curing agent than resin it will continue to cure for a VERY long time afterwards. Some chemists believe that the curing agent is never "used up" but rather is always present and hence will continue to harden the resin forever. But experience has shown that after it reaches a certain point the hardening slows a great deal. But that SAME experience is showing that this hardening continues into embrittlement after long enough. There are NO OTHER resins that offer the characteristics of epoxy or polyesters. Though you're free to invent a new chemistry. Actually, if the resin is not fully cross linked during the manufacturing process, i.e. there are unlinked covalent chemical bonds as per your posit, that is what can lead to fatigue failure. https://cyclingtips.com/2015/08/what...-carbon-frame/ But you are free to imagine other worlds where your dreams are reality. -- JS |
#43
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New Carbon Fiber Information
On Wed, 11 Jan 2017 11:51:44 -0500, Frank Krygowski
wrote: On 1/11/2017 11:19 AM, wrote: And eight years ago before my carbon fiber fork failure dumped me on my head I was climbing on steel bikes up 18% grades with a 42-23. Mind you I wasn't fast but I still don't see much sense in that. If you're a racer, fine. But if you aren't trying to go faster than someone else is pure ego. Sometimes it's not ego; it's training. FWIW, my "regular" (non-granny) gears are lower than that, and most of my bikes have triple cranks with "granny" chainrings besides, for use when absolutely necessary. But my philosophy has always been to stay out of the little granny ring during regular riding, no matter how tough the hill. I've always figured that builds up the quadriceps muscles. And stuff I've read recently confirmed that the only way to build muscle strength is to occasionally stress the muscles until they can barely pull one more time. Anyway, that's what I did in normal riding. Then if I were doing a super-long ride (over 100 miles), or doing an extended tour especially with a camping load, I'd use the opposite strategy. I'd drop into as low a gear as was reasonable at every opportunity. That way I didn't burn up the reserve of strength I'd built up from the hard pushing. The combination of those strategies seemed to work for me. I find it rather revealing that Super Tom charges up big hills (18%) with what is essentially a 2:1 gearing while the people who race up My. Washington - average 12% with sections ranging from 18 - 22% - recommend a 1:1 gearing. One can only assume that he is much, much, stronger than the professional hill climbers. (or has a far more vivid imagination) -- cheers, John B. |
#44
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New Carbon Fiber Information
On Wednesday, January 11, 2017 at 8:30:13 AM UTC-8, wrote:
On Tuesday, January 10, 2017 at 5:56:41 PM UTC-8, James wrote: On 11/01/17 08:11, wrote: On Tuesday, January 10, 2017 at 6:48:20 AM UTC-8, wrote: A friend who speaks Italian spoke with a bike builder in Italy who spoke to Ernesto Colnago. He verified that the problem with Carbon Fiber aside from possible manufacturing defects is that the resins grow more and more brittle with age. After two years or so they can grow so brittle that the ultra-lights can fail at any second. This is why Colnago will only give two year warranties and why they build their "light" bikes considerably heavier than other manufacturers. Have a good ride on your CF when you can get the same weight with an aluminum frame. I don't know how many of you besides Joerge make a habit of hard climbs. But light bikes do NOT make hard climbs much easier. In fact they add a lot of problems. Once the grade gets up to 18% you can't use low gears because on the light bikes it will lift the front wheel off of the ground. The bike will then pivot around the rear wheel and if you're ready for that you can lay the bike over before it turns down hill. That's funny. The difference between a light bike and a "normal" road bike might be a 1-2kg. Compared to the body weight of the rider at 70-80kg, this is nothing - and it is a distributed weigh loss over the entire bike, not just the front end. James, you are FAR out of it. A "light" bike now is under six kg and possibly down to 5 1/2. Experienced cyclists move their body weight forward to keep the front wheel on the ground and maintain traction with very low gears. MTB riders have been doing it for decades. Modern bicycle design with short wheelbases and long top tubes do not allow you to shift your center of gravity forward unless you can stand up. And you can't stand on the pedals on steep hills where you have to pedal circles. The way professional climbers get away with this is that they use LARGE gears. Then you don't have the leverage to lift the front wheel. BS. George Hincapie won a mountain stage of the Tour even though he is a sprinter. His gear was a 23 and that was the lowest gear of the group going over the top. Yabbut loookit his legs |
#45
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New Carbon Fiber Information
On Tuesday, January 10, 2017 at 3:06:30 PM UTC-8, wrote:
On Tuesday, January 10, 2017 at 2:26:04 PM UTC-8, wrote: On Tuesday, January 10, 2017 at 9:56:04 PM UTC+1, wrote: On Tuesday, January 10, 2017 at 11:33:43 AM UTC-8, wrote: On Tuesday, January 10, 2017 at 3:48:20 PM UTC+1, wrote: A friend who speaks Italian spoke with a bike builder in Italy who spoke to Ernesto Colnago. He verified that the problem with Carbon Fiber aside from possible manufacturing defects is that the resins grow more and more brittle with age. After two years or so they can grow so brittle that the ultra-lights can fail at any second. This is why Colnago will only give two year warranties and why they build their "light" bikes considerably heavier than other manufacturers. Have a good ride on your CF when you can get the same weight with an aluminum frame. Colnago doesn't have the know how to build light CF bikes that last and/or stiff enough so the answer of Ernesto doesn't surprise me. Something like Kodak that didn't know anything about digital camera's. Show me an aluminum frame of 850 grams. Any frame lighter than 1300 gram I prefer the CF one. YMMV. Lou Lou - what frame of ANY sort weighs a lb and three quarters? My CF frame (850 gr doesn't include fork). Last 2 seasons I rode this bike https://picasaweb.google.com/1010765...CPnlxYTUi5_zfA Best bike I ever had. I replaced the seat post with a Thomson Masterpiece because the CF Ritchey post kept creaking because of a design flaw. I saw and Eddy Merckx aluminum frame and fork that weighed 4 lbs. On steel bike maker tells me that he is making 16 lb bikes all up. What would YOU use a 12 lb all up bike for? Climbing and descending famous mountain passes in Europe for instance this year (a selection): http://lh3.googleusercontent.com/-zt...o/IMG_1499.JPG http://lh3.googleusercontent.com/-wP...o/IMG_1493.JPG http://lh3.googleusercontent.com/-fq...o/IMG_1495.JPG Lou What - are you the punk kid of the group? Your bike isn't geared particularly low. These days I'm seeing more and more compacts with a 34 on the back. And I thought my 39-28 was cheating after the 39-25. But I do carry a triple now do that anything over 14% I use the 30-25 or so. But there are VERY few extended climbs over 12% around here. While the Gavia and the Umbrail aren't particularly high they are known for their difficulty because of the speed of the climbs by the pro peloton. The first one I recognize but can't place it. The death ride is about the same sort of riding and the roads are a whole lot better. It has a total climb of around 50,000 ft. But it isn't much fun. You have people flying by you only to be laying on the ground trying to catch their breath 5 miles further on. Somewhere or another I went over a pass that was over 10,000 ft. That's when the air REALLY gets thin. Tom, are you talking about the Markleeville Death Ride? The standard version is about 15,000-16,000 feet of climbing. I did the six pass "Death Ride the 13th" that was closer to 19,000 (it included Pacific Grade and the back side of Ebbets Pass and Luther Pass), but that was a one-off deal. Ebbetts is under 9,000 feet. https://deathride.com/wp-content/upl...1/elemaplg.jpg But 9,000 is high enough if you're coming from sea level. Tioga is the highest pass in California at 9940 feet, but it's not on the Death Ride. The old Death Ride was more interesting -- Monitor/Monitor, Ebbetts, Luther and Carson. I think they dumped Luther because its the route to Lake Tahoe, and the tourists and locals probably didn't appreciate having the road shut down all day. -- Jay Beattie. |
#46
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New Carbon Fiber Information
On Wednesday, January 11, 2017 at 11:48:02 AM UTC-8, jbeattie wrote:
On Wednesday, January 11, 2017 at 11:27:12 AM UTC-8, wrote: On Tuesday, January 10, 2017 at 3:11:45 PM UTC-6, wrote: I'm not that good of a climber but I can run down most of the best around here if I'm in the mood. I can even give them a quarter mile lead on a hard climb. You must be a retired professional rider. Or you live where every rider is extremely obese. Or like to make things up and live in a fantasy world. No offense, but at 72, any young Cat 5 who couldn't beat him should take up another sport -- like darts. Among his age peers, however, he might be superman. Yeah, that's it - I'm talking about outriding LeMond in his heyday. |
#47
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New Carbon Fiber Information
On Wednesday, January 11, 2017 at 2:16:39 PM UTC-8, Frank Krygowski wrote:
On 1/11/2017 2:30 PM, wrote: On Wednesday, January 11, 2017 at 8:16:29 AM UTC-6, AMuzi wrote: I recall well the wise words of my then-roommate Rich Hammen, writing in his Competitive Cycling column under the pseudonym 'Ask Captain America': Q = Should I train spinning small gears or pushing big gears? A = To win, you need to spin big gears. -- Andrew Muzi I am always amazed when I see pro riding on TV. It shows them going along on the flat at 32-33 mph. I don't hit those speeds going down hill pedaling as hard as I can. I don't think I have ever hit those speeds on the flat even with a very strong tailwind. Well, I _used_ to be able to top 30 mph in a sprint. But that was a long time ago. And the older I get, the faster I was. ;-) Beating stop lights I can get up to a little over 30 and then can't spin any faster. I bought a 53 tooth but haven't put it on yet. |
#48
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New Carbon Fiber Information
On Wednesday, January 11, 2017 at 4:59:26 PM UTC-8, jbeattie wrote:
On Tuesday, January 10, 2017 at 3:06:30 PM UTC-8, wrote: On Tuesday, January 10, 2017 at 2:26:04 PM UTC-8, wrote: On Tuesday, January 10, 2017 at 9:56:04 PM UTC+1, wrote: On Tuesday, January 10, 2017 at 11:33:43 AM UTC-8, wrote: On Tuesday, January 10, 2017 at 3:48:20 PM UTC+1, wrote: A friend who speaks Italian spoke with a bike builder in Italy who spoke to Ernesto Colnago. He verified that the problem with Carbon Fiber aside from possible manufacturing defects is that the resins grow more and more brittle with age. After two years or so they can grow so brittle that the ultra-lights can fail at any second. This is why Colnago will only give two year warranties and why they build their "light" bikes considerably heavier than other manufacturers. Have a good ride on your CF when you can get the same weight with an aluminum frame. Colnago doesn't have the know how to build light CF bikes that last and/or stiff enough so the answer of Ernesto doesn't surprise me. Something like Kodak that didn't know anything about digital camera's. Show me an aluminum frame of 850 grams. Any frame lighter than 1300 gram I prefer the CF one. YMMV. Lou Lou - what frame of ANY sort weighs a lb and three quarters? My CF frame (850 gr doesn't include fork). Last 2 seasons I rode this bike https://picasaweb.google.com/1010765...CPnlxYTUi5_zfA Best bike I ever had. I replaced the seat post with a Thomson Masterpiece because the CF Ritchey post kept creaking because of a design flaw. I saw and Eddy Merckx aluminum frame and fork that weighed 4 lbs. On steel bike maker tells me that he is making 16 lb bikes all up. What would YOU use a 12 lb all up bike for? Climbing and descending famous mountain passes in Europe for instance this year (a selection): http://lh3.googleusercontent.com/-zt...o/IMG_1499.JPG http://lh3.googleusercontent.com/-wP...o/IMG_1493.JPG http://lh3.googleusercontent.com/-fq...o/IMG_1495.JPG Lou What - are you the punk kid of the group? Your bike isn't geared particularly low. These days I'm seeing more and more compacts with a 34 on the back. And I thought my 39-28 was cheating after the 39-25. But I do carry a triple now do that anything over 14% I use the 30-25 or so. But there are VERY few extended climbs over 12% around here. While the Gavia and the Umbrail aren't particularly high they are known for their difficulty because of the speed of the climbs by the pro peloton.. The first one I recognize but can't place it. The death ride is about the same sort of riding and the roads are a whole lot better. It has a total climb of around 50,000 ft. But it isn't much fun. You have people flying by you only to be laying on the ground trying to catch their breath 5 miles further on. Somewhere or another I went over a pass that was over 10,000 ft. That's when the air REALLY gets thin. Tom, are you talking about the Markleeville Death Ride? The standard version is about 15,000-16,000 feet of climbing. I did the six pass "Death Ride the 13th" that was closer to 19,000 (it included Pacific Grade and the back side of Ebbets Pass and Luther Pass), but that was a one-off deal. Ebbetts is under 9,000 feet. https://deathride.com/wp-content/upl...1/elemaplg.jpg But 9,000 is high enough if you're coming from sea level. Tioga is the highest pass in California at 9940 feet, but it's not on the Death Ride. The old Death Ride was more interesting -- Monitor/Monitor, Ebbetts, Luther and Carson. I think they dumped Luther because its the route to Lake Tahoe, and the tourists and locals probably didn't appreciate having the road shut down all day. -- Jay Beattie. Jesus Jay, you caught me in a typo. |
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