rim notation

[Emanuel Berg]

Today I saw a rear wheel rim with the
Torpedo 1SP hub. On the rim are the digits

20-635 18/8

* 20 can be the inner rim width in mm

* 635 is most likely the rim diameter and
familiar ISO/ETRTO tire designation, also
in mm

* 18 could be the number of spokes, as the rim
has 36 spokes (360 degree wheel) and 18*2=36
- but, the sprocket is 18T, so maybe that is
it?

* 8 - the sprocket diameter in cm? If so, the
"18T theory" is more likely.

--
underground experts united
http://user.it.uu.se/~embe8573

[Sepp Ruf]

Emanuel Berg wrote:
> Today I saw a rear wheel rim with the
> Torpedo 1SP hub. On the rim are the digits

Factory markings on a bicycle rim will not designate any sprocket dimension.

> 20-635 18/8

[trollian interpretations of "18/8"]

Smoke way less of that CO-producing stuff, instead, do finally order a
poster printed table of stainless steel qualities!

[Emanuel Berg]

Sepp Ruf wrote:

>> 20-635 18/8
>
> [trollian interpretations of "18/8"]
>
> Smoke way less of that CO-producing stuff,
> instead, do finally order a poster printed
> table of stainless steel qualities!

I didn't now that in Germany you measure the
dick in chromium and nickel percentages...

[John B.]

On Sat, 10 Mar 2018 14:21:15 +0100, Emanuel Berg <moa...@zoho.com>
wrote:

>Sepp Ruf wrote:
>
>>> 20-635 18/8
>>
>> [trollian interpretations of "18/8"]
>>
>> Smoke way less of that CO-producing stuff,
>> instead, do finally order a poster printed
>> table of stainless steel qualities!
>
>I didn't now that in Germany you measure the
>dick in chromium and nickel percentages...

18-8 is a general designation for stainless steel having approximately
(not exactly) 18% chromium and 8% nickel.

The term is very none exact and can be used for almost any of the 300
series, 302, 302HQ, 303, 304, 305, 316, etc., which do have different
properties.
--
Cheers,

John B.

[Emanuel Berg]

John B. wrote:

> 18-8 is a general designation for stainless
> steel having approximately (not exactly) 18%
> chromium and 8% nickel.
>
> The term is very none exact and can be used
> for almost any of the 300 series, 302, 302HQ,
> 303, 304, 305, 316, etc., which do have
> different properties.

OK, great!

I also found

18 Z 1/2"

on the sprocket. I suppose 18 is the number of
teeth, and 1/2" is the diameter of the wheel
axle hole .

On the hub shell, it says 36 which again
I suppose is the number of spokes (indeed
18*2=36), but it also says 2.8...?

Spokes are 2mm or 2.2mm at the elbow so perhaps
it is the spoke hole diameter in mm on the
hub flanges?

[Emanuel Berg]

> 18 Z 1/2"

The Torpedo sprockets come in different
flavors. The 3SP (Triplex/Dreigang) I have are
19T, the Duomatic is 20T.

The letter "Z" is the German "Zahn" for
"tooth", plain and simple.

The Duomatic has a sprocket, or a

Zahnkranz 1/2 x 1/8" aufsteckbar

"aufsteckbar" is "attachable" so the inches
probably refers to something that has to do
with that.

It also says

(s. Liste Nr. 196.6/8)

anyone has that one lying around?

[Mark J.]

On 3/10/2018 10:30 PM, Emanuel Berg wrote:
>> 18 Z 1/2"
>
> The Torpedo sprockets come in different
> flavors. The 3SP (Triplex/Dreigang) I have are
> 19T, the Duomatic is 20T.
>
> The letter "Z" is the German "Zahn" for
> "tooth", plain and simple.
>
> The Duomatic has a sprocket, or a
>
> Zahnkranz 1/2 x 1/8" aufsteckbar
>
> "aufsteckbar" is "attachable" so the inches
> probably refers to something that has to do
> with that.
>

1/2 x 1/8" probably refers to the appropriate chain (which does have
these measurements; 1/2" from pin to pin, and roughly 1/8" wide.)

Mark J.

[Emanuel Berg]

Mark J. wrote:

> 1/2 x 1/8" probably refers to the appropriate
> chain (which does have these measurements;
> 1/2" from pin to pin, and roughly 1/8" wide.)

Great, thanks!

[AMuzi]

On 3/11/2018 12:30 AM, Emanuel Berg wrote:
>> 18 Z 1/2"
>
> The Torpedo sprockets come in different
> flavors. The 3SP (Triplex/Dreigang) I have are
> 19T, the Duomatic is 20T.
>
> The letter "Z" is the German "Zahn" for
> "tooth", plain and simple.
>
> The Duomatic has a sprocket, or a
>
> Zahnkranz 1/2 x 1/8" aufsteckbar
>
> "aufsteckbar" is "attachable" so the inches
> probably refers to something that has to do
> with that.
>
> It also says
>
> (s. Liste Nr. 196.6/8)
>
> anyone has that one lying around?
>

Oh dear lord. Really?

3-spline sprockets are cheap and ubiquitous. They're 'quick
change' in that the previous versions (mostly prewar) were
all screw-on track sprockets. Standard format fits Sturmey,
Shimano, SRAM-Sachs-F&S-Torpedo, Bendix, Durex, Centrix, and
so on right down to $5 chinese child's coaster hubs. You can
mix-n-match across brands and tooth count, change your
gearing every morning if you like, sizes range 13t to 24t.

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

[Emanuel Berg]

AMuzi wrote:

> 3-spline sprockets are cheap and ubiquitous.
> They're 'quick change' in that the previous
> versions (mostly prewar) were all screw-on
> track sprockets. Standard format fits
> Sturmey, Shimano, SRAM-Sachs-F&S-Torpedo,
> Bendix, Durex, Centrix, and so on right down
> to $5 chinese child's coaster hubs. You can
> mix-n-match across brands and tooth count,
> change your gearing every morning if you
> like, sizes range 13t to 24t.

Another thing I have thought about doing is to
flip the sprocket which has an inclination and
is facing inwards by design/default, but
flipping it might be better than padding with
spacers/washers to get a better chain line, if
indeed it can be done without complications as
I suspect it can?

[AMuzi]

That is why sizes over 16t are offset, providing two positions.

[Frank Krygowski]

Emanuel, with all due respect, have you considered buying a book?


--
- Frank Krygowski

[Emanuel Berg]

Frank Krygowski wrote:

> Emanuel, with all due respect, have you
> considered buying a book?

These are the ones I have acquired or borrowed
from the public library. The road bike books
obviously don't cover the Torpedo rear hub, and
the Swedish books are mechanically at a lower
level than that, the Dutch one maybe covers it
but I don't read the language - it has some
good illos tho so I wouldn't rule it out.
"Effective cycling" I gave up on as it was so
boring to read with very few illustrations and
a tiresome focus on policy/traffic issues which
I can't influence anyway.

@book{complete-road-bike-maintenance,
author = {Guy Andrews},
ISBN = {978 1 4081 7093 9},
publisher = {Bloomsbury},
title = {Complete Road Bike Maintenance},
year = 2013
}

@book{en-cyklo-pedi,
author = {Johan Tell},
ISBN = {978-91-1-307337-8},
publisher = {Nordstedt},
title = {En cyklo pedi},
year = 2016
}

@book{effective-cycling,
author = {John Forester},
ISBN = {978-0-262-51694-5},
publisher = {Cambridge},
title = {Effective Cycling},
year = 2012
}

@book{bike,
author = {Daniel Benson and Richard Moore},
ISBN = 9781781312346,
publisher = {Aurum},
title = {Bike! A Tribute to the World's Greatest Cycling Designers},
year = 2014
}

@book{cykelbok,
author = {Staffan Skott},
ISBN = {91-550-3942-1},
publisher = {Tiden},
title = {Cykelbok},
year = 1994
}

@book{praktisch-fietsboek,
author = {Rob van der Plas},
ISBN = {90 274 9848 2},
publisher = {Spectrum},
title = {Praktisch Fietsboek},
year = 1984

[Emanuel Berg]

> These are the ones I have acquired or
> borrowed from the public library. The road
> bike books obviously don't cover the Torpedo
> rear hub

Actually "Bike!" does have a section on
Sturmey-Archer! However only some random
cultural/historic notes, certainly no
component-component tutorial...

[Emanuel Berg]

Frank Krygowski wrote:

> Emanuel, with all due respect, have you
> considered buying a book?

Why don't you and Liebermann write one?
AMuzi can then fill in the blanks using his own
posts that are already written and John B.
can finish the manuscript by providing one
story per chapter under "Bike Lore" (with the
letter O a spoked wheel), again just a matter
of reusing posts from rec.bicycles.tech .
I'm sure I'm forgetting someone here tho but
that will only make the book even better when
he joins as well. And yes, I promise to read
it, instantly.

[AMuzi]

You might consider a review of basic principles and prior
art besides consumer 'how to' books:

https://www.alibris.com/booksearch?keyword=archibald+sharp+bicycles&mtype=B&hs.x=0&hs.y=0

[Emanuel Berg]

AMuzi wrote:

> Standard format fits Sturmey, Shimano,
> SRAM-Sachs-F&S-Torpedo, Bendix, Durex,
> Centrix, and so on right down to $5 chinese
> child's coaster hubs.

I have also come across a Swedish coaster hub
called Nova which I'd place no later than the
1960s. Always when I see one it is spoked to
the kind of "deep" rim which looks like the
letter V and has a centerline of holes for the
spokes at the bottom of the valley, also the
rim has small brackets or oval washers between
inside the rim and the spoke nipple heads, and
those are common areas of corrosion (?) or
other material loss of freshness. Next time
I see one I'll examine if the sprocket is
standard 3-spline on this hub as well...

[Frank Krygowski]

I'm not familiar with most of those. Here are books that I have (all in
English) that might help you.

I have two Rob van der Plas books that seem appropriate for you. One is
_Bicycle Technology_ from 1991. Another is _The Bicycle Repair Book_
from 1993. Both are published by Bicycle Books Inc., Mill Valley
California. Both cover lots of basics and seem intended for novices.
Unlike most modern books, these discuss things like coaster brakes, rod
actuated brakes, 3 speed hubs, and more than the usual amount of basic
mechanical practices.

A similar approach is used in any of the various books by Richard
Ballantine. Several of his books (_Richard's Bicycle Book_, _Richard's
21st Century Bicycle Book_ etc.) confine mechanical repairs to just the
last short chapter, but he's also written _Richard's Bicycle Repair
Manual_, which I don't own. I suspect it would be good for you. I've
enjoyed his writing on other aspects of cycling.

_The Big Blue Book of Bicycle Repair_ from Park Tools USA by C. Calvin
Jones is good for modern sport bike components - at least, "modern" up
to 2005, which is my edition. It won't be much help for coaster brakes
brakes and utility bikes.

I have a year 2000 edition of Leonard Zinn's _Zinn & the Art of Road
Bike Maintenance_. It seems pretty good.

I have others, even older, but I think those would serve you well. And
as I've mentioned www.abebooks.com is a good and very inexpensive source
of used books. I hope it, or a similar used book source, is available in
your country

Of course, I hope by now you've spent a lot of time at Sheldon Brown's
site, http://www.sheldonbrown.com/ and you've used the Park Tool site's
"Repair Help" section. https://www.parktool.com/blog/repair-help/

--
- Frank Krygowski

[Emanuel Berg]

> I have also come across a Swedish coaster hub
> called Nova

*Novo

> which I'd place no later than the 1960s.
> Always when I see one it is spoked to the
> kind of "deep" rim which looks like the
> letter V and has a centerline of holes for
> the spokes at the bottom of the valley

What are the implication of this spoke/rim
interface? Less lateral strength and more
difficult to true the wheel?

[Emanuel Berg]

Frank Krygowski wrote:

> I'm not familiar with most of those. Here are
> books that I have (all in English) that might

> help you [...]

Excellent, I'll return to this when
I acquire/read them, God willing.

[Tosspot]

You are not wrong. John Forester is an asshole

https://waronthemotorist.wordpress.com/2012/07/27/john-forester-is-an-asshole/

[Frank Krygowski]

The book _Bicycles & Tricycles, An Elementary Treatise_ is probably
interesting only to those who love the history of engineering. It was
written well over 100 years ago. I enjoyed finding out what they knew
back then - which was quite a lot - but it's not useful for fixing a bike.

> You are not wrong.  John Forester is an asshole

Forester's book is also not the best for learning to work on a bike. But
the book was absolutely ground breaking, and those of us who actually
ride on public streets and roads owe Forester a great debt. He's devoted
his life to preserving cyclists' rights to the road and teaching
cyclists how to handle traffic.

His online personality is prickly indeed; but he's a brilliant thinker,
and most attacks against him come from the "bicycle facility complex."
That's the idealists who imagine we can and should build a segregated
network for bikes, parallel to our existing network of streets, and the
designers who make their money by deluding the idealists and selling
their services to cities.

When people point out that's not possible, or that the yearned-for
designs create difficult problems, those folks get nasty.

> https://waronthemotorist.wordpress.com/2012/07/27/john-forester-is-an-asshole/

--
- Frank Krygowski

[AMuzi]

On 3/12/2018 2:44 PM, Tosspot wrote:
> On 12/03/18 14:29, AMuzi wrote:
>> On 3/11/2018 11:55 PM, Emanuel Berg wrote:
>>> Frank Krygowski wrote:
>>>
>>>> Emanuel, with all due respect, have you
>>>> considered buying a book?
>>>
>>> These are the ones I have acquired or borrowed
>>> from the public library. The road bike books
>>> obviously don't cover the Torpedo rear hub, and
>>> the Swedish books are mechanically at a lower
>>> level than that, the Dutch one maybe covers it
>>> but I don't read the language - it has some
>>> good illos tho so I wouldn't rule it out.
>>> "Effective cycling" I gave up on as it was so
>>> boring to read with very few illustrations and
>>> a tiresome focus on policy/traffic issues which
>>> I can't influence anyway.
>>>
>>> @book{complete-road-bike-maintenance,

>>>   author    = {Guy Andrews},
>>> Â Â ISBNÂ Â Â Â Â Â = {978 1 4081 7093 9},
>>>   publisher = {Bloomsbury},
>>>   title     = {Complete Road Bike Maintenance},
>>>   year      = 2013
>>> }
>>>
>>> @book{en-cyklo-pedi,
>>>   author    = {Johan Tell},
>>> Â Â ISBNÂ Â Â Â Â Â = {978-91-1-307337-8},
>>>   publisher = {Nordstedt},
>>>   title     = {En cyklo pedi},
>>>   year      = 2016
>>> }
>>>
>>> @book{effective-cycling,
>>>   author    = {John Forester},
>>> Â Â ISBNÂ Â Â Â Â Â = {978-0-262-51694-5},
>>>   publisher = {Cambridge},
>>>   title     = {Effective Cycling},
>>>   year      = 2012
>>> }
>>>
>>> @book{bike,
>>>   author    = {Daniel Benson and Richard Moore},
>>> Â Â ISBNÂ Â Â Â Â Â = 9781781312346,
>>>   publisher = {Aurum},
>>>   title     = {Bike! A Tribute to the World's
>>> Greatest Cycling Designers},
>>>   year      = 2014
>>> }
>>>
>>> @book{cykelbok,
>>>   author    = {Staffan Skott},
>>> Â Â ISBNÂ Â Â Â Â Â = {91-550-3942-1},
>>>   publisher = {Tiden},
>>>   title     = {Cykelbok},
>>>   year      = 1994
>>> }
>>>
>>> @book{praktisch-fietsboek,
>>>   author    = {Rob van der Plas},
>>> Â Â ISBNÂ Â Â Â Â Â = {90 274 9848 2},
>>>   publisher = {Spectrum},
>>>   title     = {Praktisch Fietsboek},
>>>   year      = 1984

>>> }
>>>
>>
>>
>> You might consider a review of basic principles and prior
>> art besides consumer 'how to' books:
>>
>> https://www.alibris.com/booksearch?keyword=archibald+sharp+bicycles&mtype=B&hs.x=0&hs.y=0
>
>
> You are not wrong. John Forester is an asshole
>
> https://waronthemotorist.wordpress.com/2012/07/27/john-forester-is-an-asshole/
>
>
>
>

He may well be, but he's right about many things too.
Who among us is right all the time? Not me anyway.

c.f. Sen Joe McCarthy, a consummate asshole by anyone's
measure, who was largely proven right by The Venona Papers
in 1993.

[Joy Beeson]

On Mon, 12 Mar 2018 06:26:54 +0100, Emanuel Berg <moa...@zoho.com>
wrote:

> Why don't you and Liebermann write one?

I have written a book. It isn't that easy.

(Started in 1995, spent a few hours on it today.)

--
Joy Beeson
joy beeson at comcast dot net
http://wlweather.net/PAGEJOY/

[Sepp Ruf]

AMuzi wrote:
> On 3/12/2018 2:44 PM, Tosspot wrote:
>> On 12/03/18 14:29, AMuzi wrote:
>>> On 3/11/2018 11:55 PM, Emanuel Berg wrote:
>>>> Frank Krygowski wrote:
>>>>
>>>>> Emanuel, with all due respect, have you
>>>>> considered buying a book?

You don't really think a lack of paper, pencils, or posters is the
problem[1], do you?

>>>> These are the ones I have acquired or borrowed
>>>> from the public library. The road bike books
>>>> obviously don't cover the Torpedo rear hub, and
>>>> the Swedish books are mechanically at a lower
>>>> level than that, the Dutch one maybe covers it
>>>> but I don't read the language - it has some
>>>> good illos tho so I wouldn't rule it out.
>>>> "Effective cycling" I gave up on as it was so
>>>> boring to read with very few illustrations and
>>>> a tiresome focus on policy/traffic issues which
>>>> I can't influence anyway.

^^^^^^^^^
Bingo. This fits the classic definition of "idiot."

>>>> [list of books]

>>> You might consider a review of basic principles and prior
>>> art besides consumer 'how to' books:
>>>
>>> https://www.alibris.com/booksearch?keyword=archibald+sharp+bicycles&mtype=B&hs.x=0&hs.y=0

A new edition is merely 1.3 pounds? Won't fix a SWEloi's wetware issue even
if you directly hurl it at his cranium. Maybe if you bundle it with a
hardcover Sutherland's, an old Siegfrid & Fritz
<https://www.amazon.de/gp/offer-listing/3870730145/ref=dp_olp_used?ie=UTF8&condition=used>
and
<https://www.adlibris.com/se/bok/tabellenbuch-fahrradtechnik-9783808523346>

>> You are not wrong. John Forester is an asshole
>>
>> https://waronthemotorist.wordpress.com/2012/07/27/john-forester-is-an-asshole/

A quick check shows that the mob at that site even resort to misrepresenting
the deadly accidents they link to. Zero credibility.

> He may well be, but he's right about many things too.
> Who among us is right all the time? Not me anyway.

To millennial snowflakes who have never learned to properly drive or ride,
anyone surviving vehicular cycling as long as Forester has will
automatically look like an a.


--
"With some clients, make sure to collect upfront before giving free advice."

[1] <https://www.youtube.com/watch?v=irSwMr9Zxs0>
<https://www.youtube.com/watch?v=3Vlr-J9Sbww>

[Emanuel Berg]

Joy Beeson wrote:

>> Why don't you and Liebermann write one?
>
> I have written a book. It isn't that easy.
>
> (Started in 1995, spent a few hours on
> it today.)

I have also written one [1]. I know we have
a novel written on the list as well. No one said
its supposed to be easy :)

[1] http://user.it.uu.se/~embe8573/borta/

[Emanuel Berg]

> I have also written one [1]. I know we have
> a novel written

*writer

[Duane]

Maybe but it's not just millennial snowflakes that find Forester's
penchant to reject out of hand anything but his own solution to be flawed.

Case in point, the idea that adding something to trucks to keep cyclists
and pedestrians from getting under the wheels. We've had several deaths
in Montreal directly related to this.

One can sit on their pompous ass and blame the cyclist or pedestrians
for not reading their book. But putting barriers on trucks isn't a bad
idea. Nor is improved visibility. We have the tech to use cameras and
proximity alerts on my Toyota but not on an 18 wheeler? Doesn't make
much sense to be against these things in my opinion.

[Emanuel Berg]

Sepp Ruf wrote:

>> I can't influence anyway.
>

> Bingo. This fits the classic definition of
> "idiot."

*plonk*

[Frank Krygowski]

Does Forester really reject the idea of putting side guards on trucks? I doubt
it. I believe his logic is more like the following:

Cyclists occasionally get killed when they are right hooked by a large truck.
When that happens, the immediate cause of death is usually that the rear
wheels of the truck or its trailer smash the cyclist. Yes, it's a problem.

So how should a cyclist avoid that fate? One way would be to begin the lobbying
process to create a state law mandating side guards on all such trucks and
trailers. That will be opposed by the trucking industry, so it will involve
a long fight. If we start now, installation may being in, oh, five years if
we're lucky. And it's likely to apply only to new trucks, so old ones will be
running around unguarded for maybe 20 more years.

And the side guards won't be perfect - not even close. Because of the necessary
ground clearance, the guards will still fail some cyclists. In other words, the
cyclists wanting to avoid that fate will not be saved by this strategy for a
long time, if ever.

On the other hand, if a cyclist wants to avoid that fate, he could learn to
avoid getting into a right hook situation. He could drop the fantasy that a
bike lane - even a "protected bike lane" - constitutes an impenetrable barrier.

Neither of these strategies will protect the ignorant cyclists. But when
Forester talks about avoiding these right hooks, he's trying to reduce the
number of ignorant cyclists. The cyclists that really learn this will be much,
much safer.

One way to teach the lesson is to note, after one of these fatalities, that the
cyclist did make a mistake. Of course, many people castigate that as "victim
blaming." So instead of teaching, they promote fantasy solutions.

That's nuts.

I imagine what those people would have done if they'd been math teachers:
"Johnny, you said 2+2=5. I don't want to hurt your self esteem, so I'm going to
do what I can to make two plus two actually equal five. No need to thank me!
I just want to make the world a better place for everyone!"

- Frank Krygowski

[Emanuel Berg]

Is the discussion "there should be separate
lines for bicycles"?

It a great idea and here we have countless of
km of those, including in urban areas, but
surely the ambition isn't a complete
separation? That would be out of the question
here: I ride my bike 3-4 times a day and ~5% of
the time on special lines, the rest is among
the cars like everyone else.

Here, most accidents that involve a bike AND
a car, 75-80% of those happen at intersections
when the bike rider expects (?) the car to
stop, but it doesn't. [1]

[1] According to Irene Isaksson-Hellman, traffic
analyzer at If, an insurance company.

[Frank Krygowski]

Forester and others have demonstrated that the bulk of car-bike crashes
do happen at intersections. (And that every driveway is in fact an
intersection.) They've demonstrated that completely separated bike
facilities cannot be separated at intersections, where most crashes
happen. And they've pointed out that there can never be a complete
separate system getting cyclists to every point, so cyclists must learn
to ride with motor vehicle traffic anyway.

That doesn't matter. There are still lots of nut cases saying only
barrier-separated bike lanes and completely separate trails can be safe.

At this point in time, there are fewer than 250 miles barrier-separated
bike lanes in America. There are roughly 4 million miles of roads.

I guess they never plan to ride on 99.99% of the roads.


--
- Frank Krygowski

[Emanuel Berg]

Frank Krygowski wrote:

> They've demonstrated that completely
> separated bike facilities cannot be separated
> at intersections, where most crashes happen.
> And they've pointed out that there can never
> be a complete separate system getting
> cyclists to every point

In theory - why not?

In practise - difficult

In reality - won't happen as car drivers and
shopkeeper won't accept it as
aggressivity/stress/frustration would be
reduced so much people wouldn't have to buy
meaningless things all the time (or drive to
Yoga class)

[Frank Krygowski]

On Tuesday, March 13, 2018 at 11:25:36 PM UTC-4, Emanuel Berg wrote:
> Frank Krygowski wrote:
>
> > They've demonstrated that completely
> > separated bike facilities cannot be separated
> > at intersections, where most crashes happen.
> > And they've pointed out that there can never
> > be a complete separate system getting
> > cyclists to every point
>
> In theory - why not?
>
> In practise - difficult
>
> In reality - won't happen as car drivers and
> shopkeeper won't accept it as
> aggressivity/stress/frustration would be
> reduced so much people wouldn't have to buy
> meaningless things all the time (or drive to
> Yoga class)

"In theory, there's no difference between theory and practice. In practice, there is."

The reason it's impossible to build a complete separate system is not just selfishness by motorists and shopkeepers. There are many issues that
should be obvious: Expense; Property rights, as related to right-of-way
acquisition; Road geometry; Politics; Ineffectiveness; Emergency vehicle
response; Maintenance...

- Frank Krygowski

[Emanuel Berg]

Frank Krygowski wrote:

> The book _Bicycles & Tricycles, An Elementary
> Treatise_ is probably interesting only to
> those who love the history of engineering.
> It was written well over 100 years ago.
> I enjoyed finding out what they knew back
> then - which was quite a lot

Well, how fast were the fastest cars in the
early 20th century? 130 km/h?

I mean, wasn't this the Jules Verne,
ballon-to-the-north-pole, Titanic, pre-WW1
hay days of this kind'a stuff?

[jbeattie]

On Tuesday, March 13, 2018 at 8:25:36 PM UTC-7, Emanuel Berg wrote:
> Frank Krygowski wrote:
>
> > They've demonstrated that completely
> > separated bike facilities cannot be separated
> > at intersections, where most crashes happen.
> > And they've pointed out that there can never
> > be a complete separate system getting
> > cyclists to every point
>
> In theory - why not?
>
> In practise - difficult
>
> In reality - won't happen as car drivers and
> shopkeeper won't accept it as
> aggressivity/stress/frustration would be
> reduced so much people wouldn't have to buy
> meaningless things all the time (or drive to
> Yoga class)

I find bicycle traffic stressful. Morning traffic in Portland --
https://i.pinimg.com/736x/2c/bf/90/2cbf90237689c07a04bad584c86e6f64--august-events-across-the-bridge.jpg

In reality, though, bike traffic in multi-use facilities can be very stressful and equally stressful as driving in a car -- if not more so. https://c2.staticflickr.com/4/3147/2440785339_c9c11754b6_z.jpg?zz=1

-- Jay Beattie.

[Emanuel Berg]

jbeattie wrote:

> In reality, though, bike traffic in multi-use
> facilities can be very stressful and equally
> stressful as driving in a car -- if not
> more so.

People who ride bikes are not stressed.
Outdoor, movement, speed, fun, no jams: can't
fail.

OTOH people who voluntarily lock themself into
small boxes where they can yell silently at
other people who do exactly the same...

My favorite is when a car driver gets out of
the car and is angry at everyone and
everything. People ask what's the matter and he
says, the wheel door still open, that traffic
was just horrible.

[Frank Krygowski]

On 3/14/2018 1:42 AM, Emanuel Berg wrote:
> Frank Krygowski wrote:
>
>> The book _Bicycles & Tricycles, An Elementary
>> Treatise_ is probably interesting only to
>> those who love the history of engineering.
>> It was written well over 100 years ago.
>> I enjoyed finding out what they knew back
>> then - which was quite a lot
>
> Well, how fast were the fastest cars in the
> early 20th century? 130 km/h?
>
> I mean, wasn't this the Jules Verne,
> ballon-to-the-north-pole, Titanic, pre-WW1
> hay days of this kind'a stuff?

You seem to misunderstand what the book's about. I very much doubt
there's a single mention of an automobile.

The book was written in 1896, in the midst of the first great bike boom,
triggered by the combination of the "safety bicycle" chain drive system
plus the pneumatic tire. At that time, bikes were the height of
technological fashion, kind of like smartphones today. But they were
being produced by hundreds and hundreds of companies, and many details
of design were not yet understood. There was a lot of craziness in some
of the approaches, a lot of ignorant trial and error, a lot of "myth and
lore" as Jobst Brandt used to say here.

Archibald Sharp was an engineer. Supposedly he had a crusty personality,
he engaged in public correspondence in which he pointed out the folly of
various designers, and he ultimately wrote this engineering book about
bicycles, hoping that people would learn from it and the art would
thereby advance. Seems to me he was quite similar to the late Jobst
Brandt or Sheldon Brown.

The book really is an engineering textbook. It's full of free body
diagrams, stress calculations, mathematics of all kinds, illustrations
of countless designs, etc. It contains no science fiction. It's all
about understanding and applying bicycle physics and engineering.

--
- Frank Krygowski

[Joy Beeson]

On Tue, 13 Mar 2018 21:07:19 -0700 (PDT), Frank Krygowski
<frkr...@gmail.com> wrote:

> The reason it's impossible to build a complete separate system is not just selfishness by motorists and shopkeepers. There are many issues that
> should be obvious: Expense; Property rights, as related to right-of-way
> acquisition; Road geometry; Politics; Ineffectiveness; Emergency vehicle
> response; Maintenance...

speaking of geometry:

Anne McCaffrey's Pern includes a caste of messengers who have built a
network of moss-paved footpaths that connect every Hold and Weyr.
These same points are also connected by dirt paths beaten by
travellers on horseback. (Pardon me, "runner-beast"back.)

A messenger running from point A to point B never, ever crosses a
horse trail connecting point C to point D. Not so much as a cowpath!

Please draw me a map of how this works.

In "Imperial Earth", Arthur C. Clarke manages better: Since cars are
self-driving, roads are no wider than railroad tracks, and there is
only one lane in each direction. Intersections with other roads
aren't mentioned, but while being driven to his host's home, the
protagonist passes under an overpass carrying a much wider road. The
host explains to him that bicycles require more room because humans
are steering them.

[Frank Krygowski]

On 3/16/2018 12:50 AM, Joy Beeson wrote:
> On Tue, 13 Mar 2018 21:07:19 -0700 (PDT), Frank Krygowski
> <frkr...@gmail.com> wrote:
>
>> The reason it's impossible to build a complete separate system is not just selfishness by motorists and shopkeepers. There are many issues that
>> should be obvious: Expense; Property rights, as related to right-of-way
>> acquisition; Road geometry; Politics; Ineffectiveness; Emergency vehicle
>> response; Maintenance...
>
> speaking of geometry:
>
> Anne McCaffrey's Pern includes a caste of messengers who have built a
> network of moss-paved footpaths that connect every Hold and Weyr.
> These same points are also connected by dirt paths beaten by
> travellers on horseback. (Pardon me, "runner-beast"back.)
>
> A messenger running from point A to point B never, ever crosses a
> horse trail connecting point C to point D. Not so much as a cowpath!
>
> Please draw me a map of how this works.

For fans of McCaffrey, the obvious answer is that at the intersections,
one path "goes between." ;-)

But more seriously: I doubt any of the segregation proponents will
accept your challenge to draw the map.

> In "Imperial Earth", Arthur C. Clarke manages better: Since cars are
> self-driving, roads are no wider than railroad tracks, and there is
> only one lane in each direction. Intersections with other roads
> aren't mentioned, but while being driven to his host's home, the
> protagonist passes under an overpass carrying a much wider road. The
> host explains to him that bicycles require more room because humans
> are steering them.

That's slightly more realistic.

Back to the first point: Way, way back in time, I was a member of a
committee charged with finding a way to connect our village to a
riverside MUP about 7 miles away. We started with the assumption that
the MUP could be extended closer along the riverside, which in itself
would be a difficult, decade-long project. So we concentrated on finding
a route up the side of the river valley.

Briefly, there was no way. Terrain, commercial property, roadways,
freeways, private property, etc. showed it was just impossible. Besides,
there were relatively low-traffic roads that were fine for any minimally
competent cyclist. All that meant it was silly to even try.

There were times that same committee, with slightly different
objectives, looked longingly at power line rights of way or gas line
rights of way. I suppose in some ideal society, one might be able to get
a MUP along those. But they (especially the gas lines) tended to be
nowhere-to-nowhere lines. If a gas line ROW got a paved path, I'm sure
it would generate some riding; but it would be entirely by the crew that
parks the car and rides the bike out and back to the car.

--
- Frank Krygowski