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  #1  
Old December 30th 20, 12:37 AM posted to rec.bicycles.tech
Tom Kunich[_4_]
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Posts: 2,196
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I have an 11 speed manual Dura Ace 9000 series, an 8000 series Ultegra Di2 and two Di2 11 speed Dura Ace bikes. I also had a 10 speed Campy Record manual shifting bike.

As I have noted before, the 10 speed has more speeds than necessary and a 9 speed was probably too many as well. I find it hard to believe that even pros can use this many speeds and myself I spend a great deal of time shifting through the gears in the hills to get to the 4 or 5 speeds I actually use.

On the flats I also only use 4 or 5 speeds and these overlap a bit.

The one advantage of the 11 speed is that the chain is more flexible than those on the older 10 speed chain and so there is less cross chain noise if you manage to do that (usually on the high speed flats then hitting a roller.)

The latest Shimano patent is for what appears to be a wireless 12 or 13 speed Di2. SRAM has been killing them in the racing marketplace because you don't have to run wires which makes service and rebuilding easy. The other day when I had a flat and had to remove the rear wheel it accidently pulled the rear derailleur wire out and I had to stop after getting under way to plug it in again. So there are a lot of advantages to wireless. But 13 Speeds? Or maybe even 14 speeds? Wireless setups really have no limit to the speeds. You just have a rear derailleur that is designed for a specific number of speeds. I think that this would be the perfect time for Shimano to backwalk a little and allow you to set-up the thing for any number of speeds that you would like. I wouldn't mind returning to 9 speeds which is a good 8 speed setup with one additional climbing gear added. This was Armstrong's original idea and it sold like hotcakes. But now the manufacturers are stuck in a rut and think that they have to increase the numbers of speeds to sell new groups. That is already backfiring on them since fewer and fewer people are buying groups. They, like the top of the line carbon fiber bikes are simply too expensive and wear out just too fast. My 11 speed 105 chain wore out in 500 miles though the new middle range KMC seems like new after twice that.

Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?
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  #2  
Old December 30th 20, 03:04 AM posted to rec.bicycles.tech
Frank Krygowski[_2_]
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Posts: 7,511
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On Tuesday, December 29, 2020 at 6:37:07 PM UTC-5, wrote:


Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?


For non-racers, the important thing is not the number of speeds. It's having a sufficient range
for one's riding, which mostly means a sufficiently low gear. It's extremely rare to find a bike
without a sufficiently high gear. These days many, many bikes come with a high gear that's
practically useless. As Jobst pointed out many times, people now pedal downgrades in gears
so high it would be faster to coast. Anything over 100 gear inches is probably just a vanity
ornament. Anything over 110 certainly is. (We don't even have that on our tandem.)

Between 100 gear inches (52-14) and whatever low gear you feel you need, how much fine
tuning is really necessary? It's well known that power output vs. cadence is essentially flat
over a wide range; so the fine tuning is just personal preference. I suspect that over the
decades, many cyclists have gotten a "princess and pea" mentality regarding that.
They've been trained to perceive and dislike slight differences from their ideal cadence, even
though it really makes no difference.

Personally, I'm perfectly happy with a 10% difference between adjacent gears. You can
get that with five cogs and a half step front setup, although it requires double shifting
more often than many would like. So, you can get the same single shifting 8 cogs. Two
chainrings with that can give you plenty of range unless you're doing loaded touring or
pedaling a tandem or recumbent. For those cases, use a triple.

About a "forever" group, I can't say why Shimano would ever do that. It's not in their
best interests, even if it would work better for many riders.

- Frank Krygowski
  #3  
Old December 30th 20, 03:48 AM posted to rec.bicycles.tech
Sir Ridesalot
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Posts: 5,270
Default bicycle tech

On Tuesday, December 29, 2020 at 9:04:36 p.m. UTC-5, wrote:
On Tuesday, December 29, 2020 at 6:37:07 PM UTC-5, wrote:


Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?

For non-racers, the important thing is not the number of speeds. It's having a sufficient range
for one's riding, which mostly means a sufficiently low gear. It's extremely rare to find a bike
without a sufficiently high gear. These days many, many bikes come with a high gear that's
practically useless. As Jobst pointed out many times, people now pedal downgrades in gears
so high it would be faster to coast. Anything over 100 gear inches is probably just a vanity
ornament. Anything over 110 certainly is. (We don't even have that on our tandem.)

Between 100 gear inches (52-14) and whatever low gear you feel you need, how much fine
tuning is really necessary? It's well known that power output vs. cadence is essentially flat
over a wide range; so the fine tuning is just personal preference. I suspect that over the
decades, many cyclists have gotten a "princess and pea" mentality regarding that.
They've been trained to perceive and dislike slight differences from their ideal cadence, even
though it really makes no difference.

Personally, I'm perfectly happy with a 10% difference between adjacent gears. You can
get that with five cogs and a half step front setup, although it requires double shifting
more often than many would like. So, you can get the same single shifting 8 cogs. Two
chainrings with that can give you plenty of range unless you're doing loaded touring or
pedaling a tandem or recumbent. For those cases, use a triple.

About a "forever" group, I can't say why Shimano would ever do that. It's not in their
best interests, even if it would work better for many riders.

- Frank Krygowski


I like my 9-cog cassettes. I can set them up with a fairly close 7-cogs spread and then have two nice bailout cogs left over.

I've had many times when a slight variation in incline would mean a gear change that to the next lower gear was too low yet the gear I was in was too high for sustained use. Due to that, a few years back I bought two Sun Race 9-cogs cassettes and took them apart and then reassembled on as a corncob 11-19 teeth cogset for my dropbar MTB with 1.5" slick tires. I absolutely love that cogset for a lot of my really long days in the saddle. Each gear shift is just enough lower to be comfortable but without fear of spinning out or pedaling a too high a cadence.

Others needs/wants vary and what works for me may not work for them.

I don't think that Shimano or any other component manufacturer will ever make a Universal shifter as that would cut into sales of the Latest and greatest gearsets and relater shifting mechanism. The closest we ever will come to a universal gear shifter would be a return to friction shifters.

I laugh at some of the changes in bicycle components. They kept adding rear cogs until the chainstays got pretty wide and interfered with the pedal strokes of riders with larger feet. Then, suddenly, one chainring setups became the rage pushed by component makers. After a few more years of those I'll expect that the latest/greatest thing being introduced on new bikes will be a double chainring set.

Cheers
  #4  
Old December 30th 20, 03:55 AM posted to rec.bicycles.tech
AMuzi
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Posts: 13,447
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On 12/29/2020 8:48 PM, Sir Ridesalot wrote:
On Tuesday, December 29, 2020 at 9:04:36 p.m. UTC-5, wrote:
On Tuesday, December 29, 2020 at 6:37:07 PM UTC-5, wrote:


Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?

For non-racers, the important thing is not the number of speeds. It's having a sufficient range
for one's riding, which mostly means a sufficiently low gear. It's extremely rare to find a bike
without a sufficiently high gear. These days many, many bikes come with a high gear that's
practically useless. As Jobst pointed out many times, people now pedal downgrades in gears
so high it would be faster to coast. Anything over 100 gear inches is probably just a vanity
ornament. Anything over 110 certainly is. (We don't even have that on our tandem.)

Between 100 gear inches (52-14) and whatever low gear you feel you need, how much fine
tuning is really necessary? It's well known that power output vs. cadence is essentially flat
over a wide range; so the fine tuning is just personal preference. I suspect that over the
decades, many cyclists have gotten a "princess and pea" mentality regarding that.
They've been trained to perceive and dislike slight differences from their ideal cadence, even
though it really makes no difference.

Personally, I'm perfectly happy with a 10% difference between adjacent gears. You can
get that with five cogs and a half step front setup, although it requires double shifting
more often than many would like. So, you can get the same single shifting 8 cogs. Two
chainrings with that can give you plenty of range unless you're doing loaded touring or
pedaling a tandem or recumbent. For those cases, use a triple.

About a "forever" group, I can't say why Shimano would ever do that. It's not in their
best interests, even if it would work better for many riders.

- Frank Krygowski


I like my 9-cog cassettes. I can set them up with a fairly close 7-cogs spread and then have two nice bailout cogs left over.

I've had many times when a slight variation in incline would mean a gear change that to the next lower gear was too low yet the gear I was in was too high for sustained use. Due to that, a few years back I bought two Sun Race 9-cogs cassettes and took them apart and then reassembled on as a corncob 11-19 teeth cogset for my dropbar MTB with 1.5" slick tires. I absolutely love that cogset for a lot of my really long days in the saddle. Each gear shift is just enough lower to be comfortable but without fear of spinning out or pedaling a too high a cadence.

Others needs/wants vary and what works for me may not work for them.

I don't think that Shimano or any other component manufacturer will ever make a Universal shifter as that would cut into sales of the Latest and greatest gearsets and relater shifting mechanism. The closest we ever will come to a universal gear shifter would be a return to friction shifters.

I laugh at some of the changes in bicycle components. They kept adding rear cogs until the chainstays got pretty wide and interfered with the pedal strokes of riders with larger feet. Then, suddenly, one chainring setups became the rage pushed by component makers. After a few more years of those I'll expect that the latest/greatest thing being introduced on new bikes will be a double chainring set.

Cheers


Wide chainstays? Some yes, but not inherently. Road bike
wheels with 8-9-10-11-12 formats have been universally 130mm
for 32 years. In 'bicycle product cycle years' that's
forever and a day.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971


  #5  
Old December 30th 20, 10:45 AM posted to rec.bicycles.tech
Lou Holtman[_5_]
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Posts: 826
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Op woensdag 30 december 2020 om 00:37:07 UTC+1 schreef :
I have an 11 speed manual Dura Ace 9000 series, an 8000 series Ultegra Di2 and two Di2 11 speed Dura Ace bikes. I also had a 10 speed Campy Record manual shifting bike.

As I have noted before, the 10 speed has more speeds than necessary and a 9 speed was probably too many as well. I find it hard to believe that even pros can use this many speeds and myself I spend a great deal of time shifting through the gears in the hills to get to the 4 or 5 speeds I actually use.

On the flats I also only use 4 or 5 speeds and these overlap a bit.

The one advantage of the 11 speed is that the chain is more flexible than those on the older 10 speed chain and so there is less cross chain noise if you manage to do that (usually on the high speed flats then hitting a roller.)

The latest Shimano patent is for what appears to be a wireless 12 or 13 speed Di2. SRAM has been killing them in the racing marketplace because you don't have to run wires which makes service and rebuilding easy. The other day when I had a flat and had to remove the rear wheel it accidently pulled the rear derailleur wire out and I had to stop after getting under way to plug it in again. So there are a lot of advantages to wireless. But 13 Speeds? Or maybe even 14 speeds? Wireless setups really have no limit to the speeds. You just have a rear derailleur that is designed for a specific number of speeds. I think that this would be the perfect time for Shimano to backwalk a little and allow you to set-up the thing for any number of speeds that you would like. I wouldn't mind returning to 9 speeds which is a good 8 speed setup with one additional climbing gear added. This was Armstrong's original idea and it sold like hotcakes. But now the manufacturers are stuck in a rut and think that they have to increase the numbers of speeds to sell new groups. That is already backfiring on them since fewer and fewer people are buying groups. They, like the top of the line carbon fiber bikes are simply too expensive and wear out just too fast. My 11 speed 105 chain wore out in 500 miles though the new middle range KMC seems like new after twice that.

Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?


It is all about the range you need, the steps between gears you can bear/accept and the willingness to change cassettes for different terrain. So it is all about personal preference. For my riding I found that the durability didn't change much going from 9-10-11 speed so cost is not an issue for me especially when you stay with Shimano (SRAM and Campagnolo is a different matter). I am very pleased with my 2*11 speed 48/31 front 14/28 back setup on my gravel bike. In the rare case I go vertical wall climbing I can throw on a 11-32 cassette. I scratch my head with the 1*11-12-13 setups with a 9-10 tooth highest gear sprocket.

Lou
  #6  
Old December 30th 20, 03:58 PM posted to rec.bicycles.tech
Wolfgang Strobl[_4_]
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Posts: 23
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Am Tue, 29 Dec 2020 18:04:33 -0800 (PST) schrieb Frank Krygowski
:

On Tuesday, December 29, 2020 at 6:37:07 PM UTC-5, wrote:


Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?


For non-racers, the important thing is not the number of speeds. It's having a sufficient range
for one's riding, which mostly means a sufficiently low gear.


Right.


It's extremely rare to find a bike
without a sufficiently high gear.


Not around here. A lot of People still use old, cheap folding biycles or
MTB style bicyles sold in large DIY stores as a commodity item. Often,
these don't have gears high enough to allow fast riding. It is not
common, anymore, but calling it extremely rare would be misleading.


These days many, many bikes come with a high gear that's
practically useless. As Jobst pointed out many times, people now pedal downgrades in gears
so high it would be faster to coast.


Sure. But neither do I have the strength or skills Jobst had, nor do I
know a law which forces me to stick to riding behaviours which are
"performant". My road bike, bought in January 2010, has a Shimano 6703
group (3x10), 52/38/30 front, 12-25 read initialy. In the beginning of
2019, I replaced the somewhat worn middle chainring and replaced the
sprocket cluster by an 11-28 one, mostly in order to extend the low gear
for our vacation in France (Perigord). 11 vs. 12 doesn't make much
difference, I can certainly do without. But I like to be able to pedal
with low force and low cadence, instead of even lower force and a high
cadence, for example when riding down a long, but not step slope,
together with my wife, who prefers not to ride as fast as physics or her
muscles would allow. Just an example - there are many situations where
I like to have it that way.


Anything over 100 gear inches is probably just a vanity
ornament. Anything over 110 certainly is. (We don't even have that on our tandem.)

Between 100 gear inches (52-14) and whatever low gear you feel you need, how much fine
tuning is really necessary?


Gear inches is a funny measure, because it doesn't relates to anything.
Around here, we use "Entfaltung", which isn't the _diameter_ of an
equivalent penny farthing bicycles wheel, but the the circumfence of the
wheel, i.e. how far you get with one revolution.

Anyway, 14 vs 11 is more than a quarter more. When riding down a hill
with about 60 km/h, for my bicyle that would make a difference of 100
rpm vs 127 rpm. I prefer 100 rpm, thank you very much.

Have a look at a concrete example from the beginning of this month

https://www.mystrobl.de/ws/pic/fahrrad/entfaltung.jpg

I'm not that strong, but when going down a 6% ramp and with a little
tailwind, I can easily do 60 km/h, too, without going to be exhausted.


It's well known that power output vs. cadence is essentially flat
over a wide range; so the fine tuning is just personal preference.


I wouldn't call 100 rpm vs 127 rpm "fine tuning".

I suspect that over the
decades, many cyclists have gotten a "princess and pea" mentality regarding that.


A large group of not especially strong riders have got an obsession with
high cadence spinning, that's for sure. While I agree to the notion
that low cadence with high force (and insufficient riding technique) is
damaging the knees, it seems absurd to me when people riding on flat
terrain at slow speed (say: 22 km/h) do that, because they see
TdF-Riders going up a 18% slope spinning that fast, or because some
"cycling expert" told them to do so.

Recpipes that don't specify the range of application aren't worth a
dime.


They've been trained to perceive and dislike slight differences from their ideal cadence, even
though it really makes no difference.

Personally, I'm perfectly happy with a 10% difference between adjacent gears.


11/14 is a difference of 27%.

When changing from 12/25 to 11/28, I didn't really care about the 12/11
difference (9%), it is noticeable, but not that relevant. But I don't
care much about the slightly bigger jumps over the range, either. I
care about the limits, though, because, well, they _are_ limits.




You can
get that with five cogs and a half step front setup, although it requires double shifting
more often than many would like. So, you can get the same single shifting 8 cogs. Two
chainrings with that can give you plenty of range unless you're doing loaded touring or
pedaling a tandem or recumbent. For those cases, use a triple.


1x11 or 12 isn't that uncommon, anymore and 12-speed hubs sell well, for
a reason. While I'm happy with my 3x10 drive, I see the limitations.
I've broken resp. worn too many middle chainrings to find it funny,
anymore.


About a "forever" group, I can't say why Shimano would ever do that. It's not in their
best interests, even if it would work better for many riders.


I don't really understand it. People who ride much need replacement for
broken or worn parts. These are expensive, sometimes in total more
expensive than a whole group . People who don't ride much won't buy a
new bike every three years, anyway.
--
Wir danken für die Beachtung aller Sicherheitsbestimmungen
  #7  
Old December 30th 20, 06:04 PM posted to rec.bicycles.tech
Tom Kunich[_4_]
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Posts: 2,196
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On Wednesday, December 30, 2020 at 6:59:52 AM UTC-8, Wolfgang Strobl wrote:
I don't really understand it. People who ride much need replacement for
broken or worn parts. These are expensive, sometimes in total more
expensive than a whole group . People who don't ride much won't buy a
new bike every three years, anyway.


I think that my comments regarding a "forever group" were perhaps misunderstood. Everything wears out or breaks for many reasons. Having a method of setting a bike up exactly as you like it and being able to maintain it for as long as it pleases you seems to me to be a reasonable goal. I find that an 11-28 with a 50-34 is perfectly fine as a 9 speed or even an 8 speed and the gaps between gears work well. What's more, a 9 speed chain lasts all hell and gone longer than a 12 speed without wearing the cogs out.
  #8  
Old December 30th 20, 06:34 PM posted to rec.bicycles.tech
Frank Krygowski[_2_]
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Posts: 7,511
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On Wednesday, December 30, 2020 at 9:59:52 AM UTC-5, Wolfgang Strobl wrote:
Am Tue, 29 Dec 2020 18:04:33 -0800 (PST) schrieb Frank Krygowski :
On Tuesday, December 29, 2020 at 6:37:07 PM UTC-5, wrote:


Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?


For non-racers, the important thing is not the number of speeds. It's having a sufficient range
for one's riding, which mostly means a sufficiently low gear.

Right.
It's extremely rare to find a bike
without a sufficiently high gear.

Not around here. A lot of People still use old, cheap folding biycles or
MTB style bicyles sold in large DIY stores as a commodity item. Often,
these don't have gears high enough to allow fast riding. It is not
common, anymore, but calling it extremely rare would be misleading.


Folding bikes are vanishingly rare in my area. We own three (one of which is terribly low quality). Otherwise, despite my long
membership in a pretty large bike club, I know only one other person who ever bought one, and she doesn't ride it.

These days many, many bikes come with a high gear that's
practically useless. As Jobst pointed out many times, people now pedal downgrades in gears
so high it would be faster to coast.

Sure. But neither do I have the strength or skills Jobst had, nor do I
know a law which forces me to stick to riding behaviours which are
"performant".
Anything over 100 gear inches is probably just a vanity
ornament. Anything over 110 certainly is. (We don't even have that on our tandem.)

Between 100 gear inches (52-14) and whatever low gear you feel you need, how much fine
tuning is really necessary?

Gear inches is a funny measure, because it doesn't relates to anything.
Around here, we use "Entfaltung", which isn't the _diameter_ of an
equivalent penny farthing bicycles wheel, but the the circumfence of the
wheel, i.e. how far you get with one revolution.


I agree, your system (which I know as "development") is much more logical. But nobody here uses it!
Actually, most people who think of gearing talk in terms of tooth counts. They're much more likely to
say "52-14" rather than "100 gear inches" let alone "8 meters." It works well enough for them because
they would never consider a non-derailleur gear or a widely different wheel diameter. Those of us with
small wheel bikes and/or internal geared hubs need something different.

(Hmm. As I recall, Great Britain is on the 'metric system', but still using miles for distance. Do British cyclists
still talk in terms of gear inches?)

Anyway, 14 vs 11 is more than a quarter more. When riding down a hill
with about 60 km/h, for my bicyle that would make a difference of 100
rpm vs 127 rpm. I prefer 100 rpm, thank you very much.

Have a look at a concrete example from the beginning of this month

https://www.mystrobl.de/ws/pic/fahrrad/entfaltung.jpg

I'm not that strong, but when going down a 6% ramp and with a little
tailwind, I can easily do 60 km/h, too, without going to be exhausted.
It's well known that power output vs. cadence is essentially flat
over a wide range; so the fine tuning is just personal preference.

I wouldn't call 100 rpm vs 127 rpm "fine tuning".


A 6% downhill is a perfect example of wasted pedaling. IIRC, that's good for well over 40 mph or 20 m/s
by coasting. Pedaling that is probably slower than coasting in a tuck. I'd relax and enjoy the ride.


I suspect that over the
decades, many cyclists have gotten a "princess and pea" mentality regarding that.


They've been trained to perceive and dislike slight differences from their ideal cadence, even
though it really makes no difference.

Personally, I'm perfectly happy with a 10% difference between adjacent gears.

11/14 is a difference of 27%.


I'm talking about the difference between adjacent gears - as in, shifting from a 14 tooth cog to the
adjacent 15 tooth cog is only 7% change.

- Frank Krygowski
  #9  
Old December 31st 20, 12:23 AM posted to rec.bicycles.tech
Wolfgang Strobl[_4_]
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Posts: 23
Default bicycle tech

Am Wed, 30 Dec 2020 09:34:56 -0800 (PST) schrieb Frank Krygowski
:

On Wednesday, December 30, 2020 at 9:59:52 AM UTC-5, Wolfgang Strobl wrote:
Am Tue, 29 Dec 2020 18:04:33 -0800 (PST) schrieb Frank Krygowski :
On Tuesday, December 29, 2020 at 6:37:07 PM UTC-5, wrote:


Any comments about the increasing numbers of speeds, any advantage of them and if Shimano should take advantage to make a "forever" group that would shift any number of speeds, self adjusting to the spacing and width of the cogsets?

For non-racers, the important thing is not the number of speeds. It's having a sufficient range
for one's riding, which mostly means a sufficiently low gear.

Right.
It's extremely rare to find a bike
without a sufficiently high gear.

Not around here. A lot of People still use old, cheap folding biycles or
MTB style bicyles sold in large DIY stores as a commodity item. Often,
these don't have gears high enough to allow fast riding. It is not
common, anymore, but calling it extremely rare would be misleading.


Folding bikes are vanishingly rare in my area. We own three (one of which is terribly low quality). Otherwise, despite my long
membership in a pretty large bike club, I know only one other person who ever bought one, and she doesn't ride it.


Well, I don't currently own a folding bike and never did. Folding bike
like this one
ttps://www.tip-berlin.de/wp-content/uploads/2016/06/Klapprad_c_HS_4.jpg,
called "Klapprad" around here, are still in use. Not as often as, say 50
years ago, but some very old ones are still in use, for a simple reason:
nobody uses these heavily, so they don't wear as much as better bikes
do. So people who just need a junk bike use these. In addition,
average riding distances are lower in my town than in your town, but we
have more cycling traffic, so chances are good to notice suche a bike
now and then.

Bikes like these are still sold cheaply, see for example
https://www.hellweg.de/Marken/KS-Cycling/Faltrad-Cityfold-27cm-grau.html.
Unbelievable. I just checked and didn't expect that.




These days many, many bikes come with a high gear that's
practically useless. As Jobst pointed out many times, people now pedal downgrades in gears
so high it would be faster to coast.

Sure. But neither do I have the strength or skills Jobst had, nor do I
know a law which forces me to stick to riding behaviours which are
"performant".
Anything over 100 gear inches is probably just a vanity
ornament. Anything over 110 certainly is. (We don't even have that on our tandem.)

Between 100 gear inches (52-14) and whatever low gear you feel you need, how much fine
tuning is really necessary?

Gear inches is a funny measure, because it doesn't relates to anything.
Around here, we use "Entfaltung", which isn't the _diameter_ of an
equivalent penny farthing bicycles wheel, but the the circumfence of the
wheel, i.e. how far you get with one revolution.


I agree, your system (which I know as "development") is much more logical. But nobody here uses it!
Actually, most people who think of gearing talk in terms of tooth counts.


Most people I know don't think much about it at all. Actually, it isn't
that difficult to visit a local bicycle store, get some advice and by a
somewhat suitable bicycle. Most people don't have the faintest idea
about the gear ratios in teir cars transmission, either.


They're much more likely to
say "52-14" rather than "100 gear inches" let alone "8 meters." It works well enough for them because
they would never consider a non-derailleur gear or a widely different wheel diameter.


Well, people buy bicycles for their children, don't they? We started
with a tiny bike with 12" wheels, then 16", 20", 24" ... Buying new and
used bicyles with wildly varying wheel sizes is one of a many jobs a
parent has. :-)


Those of us with
small wheel bikes and/or internal geared hubs need something different.

(Hmm. As I recall, Great Britain is on the 'metric system', but still using miles for distance. Do British cyclists
still talk in terms of gear inches?)


No idea. Even here, zoll and inch still live in tools an plumbing. My
torque wrench has a 1/4"-drive, I own ratchets with 1/2", 3/8" and 1/4"
drives.


Anyway, 14 vs 11 is more than a quarter more. When riding down a hill
with about 60 km/h, for my bicyle that would make a difference of 100
rpm vs 127 rpm. I prefer 100 rpm, thank you very much.

Have a look at a concrete example from the beginning of this month

https://www.mystrobl.de/ws/pic/fahrrad/entfaltung.jpg

I'm not that strong, but when going down a 6% ramp and with a little
tailwind, I can easily do 60 km/h, too, without going to be exhausted.
It's well known that power output vs. cadence is essentially flat
over a wide range; so the fine tuning is just personal preference.

I wouldn't call 100 rpm vs 127 rpm "fine tuning".


A 6% downhill is a perfect example of wasted pedaling.


On a perfect road, perhaps. I have various examples here, where I can
accelerate to that speed and _then_ coast for a while, but won't reach
that speed without heavy pedaling.

Did you notice that 58 km/h (~16 m/s) needs roughly 300 W in the
situation depicted above? 100 rpm seems like a good fit for that. That's
what you get with 52/11


IIRC, that's good for well over 40 mph or 20 m/s
by coasting.


Just by coasting, in a position which is doable on a road with traffic?
I doubt it. 20 m/s or 72 km/h will need a steep slope of about 10% and
sufficient length. 6% is good for about 55 km/h, both according to my
calculator and my experience.

Pedaling that is probably slower than coasting in a tuck. I'd relax and enjoy the ride.


Won't work. We aren't in the Alps, around here. Steep slopes usually
end faster than one gets to speed, around here.




I suspect that over the
decades, many cyclists have gotten a "princess and pea" mentality regarding that.


They've been trained to perceive and dislike slight differences from their ideal cadence, even
though it really makes no difference.

Personally, I'm perfectly happy with a 10% difference between adjacent gears.

11/14 is a difference of 27%.


I'm talking about the difference between adjacent gears - as in, shifting from a 14 tooth cog to the
adjacent 15 tooth cog is only 7% change.


11 tooth or 14 tooth on the smallest cog doesn't have a difference to
the next smaller cog, because there is none. I was still questioning
your remark

Between 100 gear inches (52-14) and whatever low gear you feel you need, how much fine
tuning is really necessary?


I don't really care about the difference between 12 and 11 teeth, but I
_do_ care if I have an 11 (or 12) teeth cog below 14 or not. Because it
does make a difference in situations I care about. Actually, I do care
about it and like it that way, because I _don't_ depend on that fine
tuning wrt. the gears between 11 and 28 (or 12 and 25 before).

Actually, I'm doing exactly what you initially suggested for non-racers:
I value the range of my gears, not the number of speeds. 11-28 instead
of 12-25 extends the range. It may change the number of speeds too, or
it may not. In my view, it does not, but I don't really care.
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  #10  
Old December 31st 20, 03:03 AM posted to rec.bicycles.tech
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On 12/30/2020 3:23 PM, Wolfgang Strobl wrote:

snip

Actually, I'm doing exactly what you initially suggested for non-racers:
I value the range of my gears, not the number of speeds. 11-28 instead
of 12-25 extends the range. It may change the number of speeds too, or
it may not. In my view, it does not, but I don't really care.


In my area folding bicycles are very common. Just in my own little
neighborhood I see bike fridays, Dahons, and Bromptons. My next door
neighbor has a higher-end Dahon, and they are not even really into
bicycling.

The big reason for folding bicycles is to not get bumped from the
Caltrain commuter train which limits the number of bicycles per train.
It used to be necessary to use a folder on BART which prohibited regular
bicycles during peak commute hours but they've since dropped that
restriction.

Even though the Caltrain bicycle capacity has gone way up over the
years, it's still not enough during normal, non-pandemic, times during
commute hours, on the express trains. Depending on the equipment, each
train can carry 72 or 80 bicycles. But because of the lack of viable
transit from train stations to housing-rich or jobs-rich areas, a LOT of
passengers want to bring their bicycles. Folding bicycles are much less
trouble because you don't constantly have to be jumping up to be moving
bicycles around so people can get their bikes off at the right station
and you don't have to worry about theft. Also, regular bicycles tend to
get banged up a lot on the train.

While the low gears on my Dahon Speed TR (SRAM Dual Drive 3x7) are
sufficient for most hills, the high gears leave something to be desired
in some cases.

On my old touring bicycle I have a 52/14 which is 97.57 gear inches and
on occasion I've wanted something higher, maybe around 105 to 110, but
back then the rear cluster on a touring bicycle was typically 14-34, and
the largest front chainring was 52.
 




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