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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