![]() |
View
New Forum Topics Today's Forum Topics Set as homepage |
|
|||||||
| |
||||
Welcome to CyclingForums.com You are currently viewing our website as a guest which gives you limited access to view most discussions. You will have to register before you can post to this thread. By joining our free online community you will have access to post new topics, communicate privately with other cyclingforums.com members (PM), respond to polls, upload photos and access other special features like product reviews and classifieds. |
|
|
Thread Tools | Search this Thread | Display Modes |
|
|
#1 |
|
Guest
Posts: n/a
|
On Fri, 20 Jun 2008 00:40:52 -0600, carlfogel@comcast.net wrote:
>Alas, the calculators predict that Joe was yet another victim of >weight-weenie wishful thinking--surely you should be able to feel the >difference when you start pushing the pedals of a bike 1/3 lighter! You might not be able to feel the difference in speed (though 3% is conceivably noticeble), but you surely can feel some difference (perhaps it's handling, perhaps it's stability/instaility). Funny that a difference that large in bike weight is derided as weigh-weeniness. Funny that 3% in time is considered weeniness. Dear Carl. Please place a six pound piece of lead on your bike and leave it there for the next year or so. Cheers, JT |
|
|
|
#2 |
|
Guest
Posts: n/a
|
On Fri, 20 Jun 2008 09:52:42 GMT, John Forrest Tomlinson
<usenetremove@jt10000.com> wrote: >You might not be able to feel the difference in speed (though 3% is >conceivably noticeble), but you surely can feel some difference >(perhaps it's handling, perhaps it's stability/instaility). I think "handling" is the major difference that folks notice. The lighter bike is a little easier to push around the road. I see the same thing with (much) lighter sports cars - although they may have the same, or often lower ratings on the skid pad, they are still a lot more fun to toss around the road. >Funny that a difference that large in bike weight is derided as >weigh-weeniness. Funny that 3% in time is considered weeniness. 3% matters in the TDF. On a pleasure ride, it would have to be much more. > >Dear Carl. Please place a six pound piece of lead on your bike and >leave it there for the next year or so. Interesting idea. Carl? |
|
|
|
#3 |
|
Guest
Posts: n/a
|
On Fri, 20 Jun 2008 15:02:40 GMT, still just me
<wheeledBobNOSPAM@yahoo.com> wrote: >3% matters in the TDF. On a pleasure ride, it would have to be much >more. It matters in even lower level racing. It might even "matter" if you're just trying to beat your buddy up a long hill. That's up to the rider what matters -- if the result of the ride is different and noticeable, then it matters. Heck, 3% is 100 times as good if you win something instead of losing. |
|
|
|
#4 |
|
Guest
Posts: n/a
|
On Fri, 20 Jun 2008 09:52:42 GMT, John Forrest Tomlinson
<usenetremove@jt10000.com> wrote: >On Fri, 20 Jun 2008 00:40:52 -0600, carlfogel@comcast.net wrote: > >>Alas, the calculators predict that Joe was yet another victim of >>weight-weenie wishful thinking--surely you should be able to feel the >>difference when you start pushing the pedals of a bike 1/3 lighter! > >You might not be able to feel the difference in speed (though 3% is >conceivably noticeble), but you surely can feel some difference >(perhaps it's handling, perhaps it's stability/instaility). > >Funny that a difference that large in bike weight is derided as >weigh-weeniness. Funny that 3% in time is considered weeniness. > >Dear Carl. Please place a six pound piece of lead on your bike and >leave it there for the next year or so. > >Cheers, > >JT Dear John, Joe explicitly talked about "forward thrust" and "cruising speed," not stability or handling, neither of which are likely to be noticeable on a 92-mile Ride-the-Rockies tour on the highway--pavement posted at 65 mph doesn't usually highlight subtle handling improvements. What time difference would you predict adding seven pounds to my current ~220 pound bicycle-and-rider combination (steel with frame bag, seat bag, and camera bag) would make at my average speed on a daily 15-mile ride, which is back down to just under 50 minutes after illness? Would the improvement in my "forward thrust" be "noticeably robust" without a stop watch? It's a tiny 0.5 km/h for a smaller rider on a 6% grade? Would I start "cruising at a more-than-respectable" clip? The improvement is less than a practically unmeasurable 0.1 km/h on the flats. Let's see . . . First, let's pretend that it's a flat ride, ignoring that 400-foot ridge west of town. 15.1 miles = 24.35 km 24.35 km / (5/6 hour) = 29.22 km/h 190 lb rider = 86.4 kg 5,000 feet = 1523 meters 25 lb bike = 11.4 kg 32 lb bike = 14.5 kg A sizzling 138 watts predicts the desired 29.2 km/h for the 86.4 kg rider and 11.4 kg bike on this side-by-side calculator: http://bikecalculator.com/veloMetricNum.html Raising the bike weight seven pounds to 14.5 kg lowers the speed from 29.25 km/h to 29.14 km/h, 0.11 km/h slower. It takes an extra 2 kcal. Time rises from 49.95 to 50.14 minutes, 0.19 minutes. That's 11.4 seconds on a 3,000 second ride. In other words, you'd need a lot of rides, a stopwatch, and a big spreadsheet to show the difference in real life. (My daily time varies considerably more than 11.4 seconds because of the wind.) No human being can detect that difference without instruments. It's a good example of how we pursue real improvements that are too small to measure outside of laboratory-control conditions. In real life, the lighter bike should indeed be ever-so-slightly faster. But real life variables like wind, temperature, barometric pressure, tire inflation, and what you ate for breakfast yesterday will swamp that tiny improvement--we're kidding ourselves when we think that we can "feel" a bike cruising 0.11 km/h faster at 29 km/h. Joe was riding an unfamiliar 92-mile stretch of mountain highway with plenty of encouragement and even pressure to believe that there was a "robust" improvement in how fast he could go. Limit the test to a 6% grade and you'll get a bigger difference, but it's still too small for a human being riding on his own on an unfamiliar stretch of highway to detect, even with a good cyclometer. You're grinding 13.5 km/h up this new road on a 92-mile ride. You don't know whether someone has put 7 pounds of lead weights in your bike's frame. Are you going faster or slower? The lead weights will change your speed, one way or the other, only 0.5 km/h. If you know that you're riding an $8500 bike that's 7 pounds lighter, you're likely to believe that you're going much faster. I'm sure that Joe "felt" the speed differences, but adding or removing 7 pounds doesn't make a difference that anyone can detect on that 92-mile ride with the seat of his pants. It takes a stopwatch and plenty of tests to tease that kind of tiny speed difference out of real rides. Cheers, Carl Fogel |
|
|
|
#5 |
|
Guest
Posts: n/a
|
Carl Fogel wrote:
>>> Alas, the calculators predict that Joe was yet another victim of >>> weight-weenie wishful thinking--surely you should be able to feel >>> the difference when you start pushing the pedals of a bike 1/3 >>> lighter! >> You might not be able to feel the difference in speed (though 3% is >> conceivably noticeble), but you surely can feel some difference >> (perhaps it's handling, perhaps it's stability/instaility). >> Funny that a difference that large in bike weight is derided as >> weigh-weeniness. Funny that 3% in time is considered weeniness. >> Dear Carl. Please place a six pound piece of lead on your bike and >> leave it there for the next year or so. > Joe explicitly talked about "forward thrust" and "cruising speed," > not stability or handling, neither of which are likely to be > noticeable on a 92-mile Ride-the-Rockies tour on highway pavement > posted at 65 mph doesn't usually highlight subtle handling > improvements. > What time difference would you predict adding seven pounds to my > current ~220 pound bicycle-and-rider combination (steel with frame > bag, seat bag, and camera bag) would make at my average speed on a > daily 15-mile ride, which is back down to just under 50 minutes > after illness? > Would the improvement in my "forward thrust" be "noticeably robust" > without a stop watch? It's a tiny 0.5 km/h for a smaller rider on a > 6% grade? > Would I start "cruising at a more-than-respectable" clip? The > improvement is less than a practically unmeasurable 0.1 km/h on the > flats. When reading these promotional phrases by unwitting shills, I think they don't ride any significant distances on climbs (like Mt. Evans) or the mountains around here: http://www.rntl.net/mthamiltonlookout.htm 4209ft above the Santa Clara Valley and across the other side, the coast range of 3000 to 4000ft mountains. > Let's see... > First, let's pretend that it's a flat ride, ignoring that 400-foot > ridge west of town. > 15.1 miles = 24.35 km > 24.35 km / (5/6 hour) = 29.22 km/h > 190 lb rider = 86.4 kg > 5,000 feet = 1523 meters > 25 lb bike = 11.4 kg > 32 lb bike = 14.5 kg > A sizzling 138 watts predicts the desired 29.2 km/h for the 86.4 kg > rider and 11.4 kg bike on this side-by-side calculator: http://bikecalculator.com/veloMetricNum.html > Raising the bike weight seven pounds to 14.5 kg lowers the speed > from 29.25 km/h to 29.14 km/h, 0.11 km/h slower. > It takes an extra 2 kcal. > Time rises from 49.95 to 50.14 minutes, 0.19 minutes. That's 11.4 > seconds on a 3,000 second ride. > In other words, you'd need a lot of rides, a stopwatch, and a big > spreadsheet to show the difference in real life. (My daily time > varies considerably more than 11.4 seconds because of the wind.) > No human being can detect that difference without instruments. > It's a good example of how we pursue real improvements that are too > small to measure outside of laboratory-control conditions. > In real life, the lighter bike should indeed be ever-so-slightly > faster. But real life variables like wind, temperature, barometric > pressure, tire inflation, and what you ate for breakfast yesterday > will swamp that tiny improvement--we're kidding ourselves when we > think that we can "feel" a bike cruising 0.11 km/h faster at 29 > km/h. > Joe was riding an unfamiliar 92-mile stretch of mountain highway > with plenty of encouragement and even pressure to believe that there > was a "robust" improvement in how fast he could go. > Limit the test to a 6% grade and you'll get a bigger difference, but > it's still too small for a human being riding on his own on an > unfamiliar stretch of highway to detect, even with a good > cyclometer. > You're grinding 13.5 km/h up this new road on a 92-mile ride. You > don't know whether someone has put 7 pounds of lead weights in your > bike's frame. > Are you going faster or slower? The lead weights will change your > speed, one way or the other, only 0.5 km/h. > If you know that you're riding an $8500 bike that's 7 pounds > lighter, you're likely to believe that you're going much faster. > I'm sure that Joe "felt" the speed differences, but adding or > removing 7 pounds doesn't make a difference that anyone can detect > on that 92-mile ride with the seat of his pants. It takes a > stopwatch and plenty of tests to tease that kind of tiny speed > difference out of real rides. I think that trying to reduce it to more than total rider and bicycle weight times the gradient is not understood by people who believe these promotional phrases. Jobst Brandt |
|
|
|
#6 |
|
Guest
Posts: n/a
|
On 2008-06-20, carlfogel@comcast.net <carlfogel@comcast.net> wrote:
> On Fri, 20 Jun 2008 09:52:42 GMT, John Forrest Tomlinson ><usenetremove@jt10000.com> wrote: > >>On Fri, 20 Jun 2008 00:40:52 -0600, carlfogel@comcast.net wrote: [...] >>Dear Carl. Please place a six pound piece of lead on your bike and >>leave it there for the next year or so. >> >>Cheers, >> >>JT > > Dear John, > > Joe explicitly talked about "forward thrust" and "cruising speed," not > stability or handling, neither of which are likely to be noticeable on > a 92-mile Ride-the-Rockies tour on the highway--pavement posted at 65 > mph doesn't usually highlight subtle handling improvements. > > What time difference would you predict adding seven pounds to my > current ~220 pound bicycle-and-rider combination (steel with frame > bag, seat bag, and camera bag) would make at my average speed on a > daily 15-mile ride, which is back down to just under 50 minutes after > illness? > > Would the improvement in my "forward thrust" be "noticeably robust" > without a stop watch? It's a tiny 0.5 km/h for a smaller rider on a 6% > grade? > > Would I start "cruising at a more-than-respectable" clip? The > improvement is less than a practically unmeasurable 0.1 km/h on the > flats. > > Let's see . . . > > First, let's pretend that it's a flat ride, ignoring that 400-foot > ridge west of town. > > 15.1 miles = 24.35 km > > 24.35 km / (5/6 hour) = 29.22 km/h > > 190 lb rider = 86.4 kg > > 5,000 feet = 1523 meters > > 25 lb bike = 11.4 kg > > 32 lb bike = 14.5 kg > > A sizzling 138 watts predicts the desired 29.2 km/h for the 86.4 kg > rider and 11.4 kg bike on this side-by-side calculator: > http://bikecalculator.com/veloMetricNum.html > > Raising the bike weight seven pounds to 14.5 kg lowers the speed from > 29.25 km/h to 29.14 km/h, 0.11 km/h slower. > > It takes an extra 2 kcal. > > Time rises from 49.95 to 50.14 minutes, 0.19 minutes. That's 11.4 > seconds on a 3,000 second ride. > > In other words, you'd need a lot of rides, a stopwatch, and a big > spreadsheet to show the difference in real life. (My daily time varies > considerably more than 11.4 seconds because of the wind.) > > No human being can detect that difference without instruments. I'm not so sure: human beings are capable of extraordinary sensitivity to unexpected things. A snooker player for example will know at once if you've exchanged his favourite cue for another one that's practically identical. A racing driver could tell if you'd changed his tyres for ones that were a little bit more or less worn (even though the difference in speed might be less than a second over a lap). So maybe the nice bike does really _feel_ nicer to some riders, even if the differences on paper only matter if you're racing at a high level. |
|
|
|
#7 |
|
Guest
Posts: n/a
|
"Ben C" <spamspam@spam.eggs> wrote in message
news:slrng5o9bh.5ne.spamspam@bowser.marioworld... > > I'm not so sure: human beings are capable of extraordinary sensitivity > to unexpected things. A snooker player for example will know at once if > you've exchanged his favourite cue for another one that's practically > identical. A racing driver could tell if you'd changed his tyres for > ones that were a little bit more or less worn (even though the > difference in speed might be less than a second over a lap). > > So maybe the nice bike does really _feel_ nicer to some riders, even if > the differences on paper only matter if you're racing at a high level. Test after test shows that human beings - even the most sensitive ones - can't tell the difference between even very familiar things if that difference is below about 2%. I thought that I could tell my Look KG241 from my Basso Loto but after trying to tell the difference in ride the only thing I could detect was that when you hit a really large bump the steel bike jumps more than the carbon fiber one. And that difference is probably 5% in flex. |
|
|
|
#8 |
|
Guest
Posts: n/a
|
On 20 Jun 2008 20:11:28 GMT, jobst.brandt@stanfordalumni.org wrote:
>Carl Fogel wrote: [snip] >> Would the improvement in my "forward thrust" be "noticeably robust" >> without a stop watch? It's a tiny 0.5 km/h for a smaller rider on a >> 6% grade? > >> Would I start "cruising at a more-than-respectable" clip? The >> improvement is less than a practically unmeasurable 0.1 km/h on the >> flats. > >When reading these promotional phrases by unwitting shills, I think >they don't ride any significant distances on climbs (like Mt. Evans) >or the mountains around here: > >http://www.rntl.net/mthamiltonlookout.htm > >4209ft above the Santa Clara Valley and across the other side, the >coast range of 3000 to 4000ft mountains. [snip calculations] >I think that trying to reduce it to more than total rider and bicycle >weight times the gradient is not understood by people who believe >these promotional phrases. > >Jobst Brandt Dear Jobst, You're probably right that going through the details with the calculators is more than some posters are willing to follow. There's a tiny improvement when a bike loses 7 pounds, but we agree it's not likely to be anything that a rider can actually notice. When I read the Ride-the-Rockies article about the lighter bike's "robust forward thrust," I couldn't help thinking of you happily riding up Alpine passes and California climbs that daunt most riders. I suspect that the secret of your "robust forward thrust" is not an ultra-light $8500 10-speed carbon-fiber frame disguised as a yellow steel 6 or 7 speed: http://i1.tinypic.com/505ukc2.jpg Enviously, Carl Fogel |
|
|
|
#9 |
|
Guest
Posts: n/a
|
On Fri, 20 Jun 2008 16:05:55 -0600, carlfogel@comcast.net wrote:
>Dear Jobst, > >You're probably right that going through the details with the >calculators is more than some posters are willing to follow. Dear Carl. Please add six pounds to your bike overwhateve it is now. It shouldn't be costly. Indeed, you might even do so in a way that makes your machine more durable Cheers, JT |
|
|
|
#10 |
|
Guest
Posts: n/a
|
On Jun 20, 6:10*pm, John Forrest Tomlinson <usenetrem...@jt10000.com>
wrote: > On Fri, 20 Jun 2008 16:05:55 -0600, carlfo...@comcast.net wrote: > >Dear Jobst, > > >You're probably right that going through the details with the > >calculators is more than some posters are willing to follow. > > Dear Carl. > > Please add six pounds to your bike overwhateve it is now. *It > shouldn't be costly. *Indeed, you might even do so in a way that makes > your machine more durable I can only repeat, sort of, that instead of adding weight, Mr. Fogel should go the other direction, maybe get a ride on one of those demonstrators he mentioned. Kind of like seeing how the other half lives, if you will. --D-y |
|
|
|
#11 |
|
Guest
Posts: n/a
|
On Fri, 20 Jun 2008 16:47:24 -0500, Ben C <spamspam@spam.eggs> wrote:
>On 2008-06-20, carlfogel@comcast.net <carlfogel@comcast.net> wrote: >> On Fri, 20 Jun 2008 09:52:42 GMT, John Forrest Tomlinson >><usenetremove@jt10000.com> wrote: >> >>>On Fri, 20 Jun 2008 00:40:52 -0600, carlfogel@comcast.net wrote: >[...] >>>Dear Carl. Please place a six pound piece of lead on your bike and >>>leave it there for the next year or so. >>> >>>Cheers, >>> >>>JT >> >> Dear John, >> >> Joe explicitly talked about "forward thrust" and "cruising speed," not >> stability or handling, neither of which are likely to be noticeable on >> a 92-mile Ride-the-Rockies tour on the highway--pavement posted at 65 >> mph doesn't usually highlight subtle handling improvements. >> >> What time difference would you predict adding seven pounds to my >> current ~220 pound bicycle-and-rider combination (steel with frame >> bag, seat bag, and camera bag) would make at my average speed on a >> daily 15-mile ride, which is back down to just under 50 minutes after >> illness? >> >> Would the improvement in my "forward thrust" be "noticeably robust" >> without a stop watch? It's a tiny 0.5 km/h for a smaller rider on a 6% >> grade? >> >> Would I start "cruising at a more-than-respectable" clip? The >> improvement is less than a practically unmeasurable 0.1 km/h on the >> flats. >> >> Let's see . . . >> >> First, let's pretend that it's a flat ride, ignoring that 400-foot >> ridge west of town. >> >> 15.1 miles = 24.35 km >> >> 24.35 km / (5/6 hour) = 29.22 km/h >> >> 190 lb rider = 86.4 kg >> >> 5,000 feet = 1523 meters >> >> 25 lb bike = 11.4 kg >> >> 32 lb bike = 14.5 kg >> >> A sizzling 138 watts predicts the desired 29.2 km/h for the 86.4 kg >> rider and 11.4 kg bike on this side-by-side calculator: >> http://bikecalculator.com/veloMetricNum.html >> >> Raising the bike weight seven pounds to 14.5 kg lowers the speed from >> 29.25 km/h to 29.14 km/h, 0.11 km/h slower. >> >> It takes an extra 2 kcal. >> >> Time rises from 49.95 to 50.14 minutes, 0.19 minutes. That's 11.4 >> seconds on a 3,000 second ride. >> >> In other words, you'd need a lot of rides, a stopwatch, and a big >> spreadsheet to show the difference in real life. (My daily time varies >> considerably more than 11.4 seconds because of the wind.) >> >> No human being can detect that difference without instruments. > >I'm not so sure: human beings are capable of extraordinary sensitivity >to unexpected things. A snooker player for example will know at once if >you've exchanged his favourite cue for another one that's practically >identical. A racing driver could tell if you'd changed his tyres for >ones that were a little bit more or less worn (even though the >difference in speed might be less than a second over a lap). > >So maybe the nice bike does really _feel_ nicer to some riders, even if >the differences on paper only matter if you're racing at a high level. Dear Ben, Try to find someone who can detect without instruments the speed difference on 92 miles of Colorado highway caused by removing 7 pounds from a bicycle. "Feel" is not really the question. Replies have wandered off into handling and agility and vibration and so forth, but Joe Hudson's comments were about "forward thrust" and "cruising speed," which are objective matters of how far you go in a given time. If Joe can "feel" the difference of 0.1 km/h in crusing speed, he's more sensitive than most cyclocomputers and somehow corrects for road roughness, air temperature, altitude, and quite a few other factors. As for racing drivers, that's pretty much a myth. They rely on the pit crew's stop watches to find out what equipment combinations are actually faster. Their "feelings" about speed are notoriously unreliable, which is hardly surprising, given the tremendous physical stress of modern car racing and the tiny differences involved in lap times. Without electronic timing, modern racing would be chaos. If you're interested, "The Physics of NASCAR" gives some details about such things. Cheers, Carl Fogel |
|
|
|
#12 |
|
Guest
Posts: n/a
|
On 2008-06-21, carlfogel@comcast.net <carlfogel@comcast.net> wrote:
> On Fri, 20 Jun 2008 16:47:24 -0500, Ben C <spamspam@spam.eggs> wrote: > >>On 2008-06-20, carlfogel@comcast.net <carlfogel@comcast.net> wrote: [...] >>> Time rises from 49.95 to 50.14 minutes, 0.19 minutes. That's 11.4 >>> seconds on a 3,000 second ride. >>> >>> In other words, you'd need a lot of rides, a stopwatch, and a big >>> spreadsheet to show the difference in real life. (My daily time varies >>> considerably more than 11.4 seconds because of the wind.) >>> >>> No human being can detect that difference without instruments. >> >>I'm not so sure: human beings are capable of extraordinary sensitivity >>to unexpected things. A snooker player for example will know at once if >>you've exchanged his favourite cue for another one that's practically >>identical. A racing driver could tell if you'd changed his tyres for >>ones that were a little bit more or less worn (even though the >>difference in speed might be less than a second over a lap). >> >>So maybe the nice bike does really _feel_ nicer to some riders, even if >>the differences on paper only matter if you're racing at a high level. > > Dear Ben, > > Try to find someone who can detect without instruments the speed > difference on 92 miles of Colorado highway caused by removing 7 pounds > from a bicycle. > > "Feel" is not really the question. Replies have wandered off into > handling and agility and vibration and so forth, but Joe Hudson's > comments were about "forward thrust" and "cruising speed," which are > objective matters of how far you go in a given time. > > If Joe can "feel" the difference of 0.1 km/h in crusing speed, he's > more sensitive than most cyclocomputers and somehow corrects for road > roughness, air temperature, altitude, and quite a few other factors. > > As for racing drivers, that's pretty much a myth. They rely on the pit > crew's stop watches to find out what equipment combinations are > actually faster. Their "feelings" about speed are notoriously > unreliable, which is hardly surprising, given the tremendous physical > stress of modern car racing and the tiny differences involved in lap > times. Without electronic timing, modern racing would be chaos. If > you're interested, "The Physics of NASCAR" gives some details about > such things. You make a good case, and I think you're probably right. |
|
|
|
#13 |
|
Guest
Posts: n/a
|
<carlfogel@comcast.net> wrote in message
news:h32p54ps4b9poso8qi7d5i2ilbofr5erq7@4ax.com... > > As for racing drivers, that's pretty much a myth. They rely on the pit > crew's stop watches to find out what equipment combinations are > actually faster. Their "feelings" about speed are notoriously > unreliable, which is hardly surprising, given the tremendous physical > stress of modern car racing and the tiny differences involved in lap > times. Without electronic timing, modern racing would be chaos. If > you're interested, "The Physics of NASCAR" gives some details about > such things. Actually when I worked with racing motorcycles the opinions of the riders were almost irrelevant. Many time a faster engine would feel slower simply because I'd widened the power band and that caused the bike to accelerate more smoothly and the rider would swear it was slower despite what the watch said. |
|
|
|
#14 |
|
Guest
Posts: n/a
|
On Fri, 20 Jun 2008 23:01:03 -0600, carlfogel@comcast.net wrote:
>Try to find someone who can detect without instruments the speed >difference on 92 miles of Colorado highway caused by removing 7 pounds >from a bicycle. Dear Carl, If it doesn't matter, we can only assume you are happy to add the 7. |
|
|
|
#15 |
|
Guest
Posts: n/a
|
On Jun 21, 8:52*am, John Forrest Tomlinson <usenetrem...@jt10000.com>
wrote: > On Fri, 20 Jun 2008 23:01:03 -0600, carlfo...@comcast.net wrote: > >Try to find someone who can detect without instruments the speed > >difference on 92 miles of Colorado highway caused by removing 7 pounds > >from a bicycle. > > Dear Carl, > > If it doesn't matter, we can only assume you are happy to add the 7. Improved roadholding. --D-y |
|