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  #11  
Old May 19th 18, 05:02 PM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 2,833
Default may or may not be 'tech'

On Sat, 19 May 2018 07:40:08 -0500, AMuzi wrote:

On 5/19/2018 2:34 AM, Jeff Liebermann wrote:
On Fri, 18 May 2018 20:02:04 -0500, AMuzi wrote:

Go though the linked brochure images. It's amateurish IMHO.


I didn't see a link to a brochure.

Maybe this is what you're thinking of:
https://books.google.com/books?id=4bSABo8Akh4C&pg=PA105&lpg=PA105#v=onepage &q&f=false
It sure doesn't look like it were made from any form of known plastic.
Oh, now I see why:
"Although this prototype had many steel parts, final
model is scheduled to have plastic frame, forks, handlebars,
gears, chain, hubs, and derailleur. Rim and cranks will
be alloy."
I wanna see the plastic gears in action. In other words, what you see
in the "prototype" photo is nothing even close to what is described,
planned, or expected.


Try this catalog link:
http://www.velo-pages.com/main.php?g2_itemId=27603

notably:
http://www.velo-pages.com/main.php?g2_itemId=27633


http://www.velo-pages.com/main.php?g2_itemId=27633&g2_imageViewsIndex=1
In 1973, we didn't have Photoshop, so the pictures look like they
might have been colorized in a darkroom onto film or paper using color
filters. The sharp edges on the various parts suggest that the parts
were not painted, which would have more rounded edges. The crankset
shows threaded hardware, without metal inserts, which is unlikely to
be the way a plastic crankset would be built. There's also no
indication of any tooth wear, which is what I would expect with a
plastic gear and a steel chain. The parts shown look exactly like the
metal equivalents, which is too much of a coincidence to be
believable. Plastic is much weaker than metal and therefore requires
thicker parts, reinforcing ribs, and metal inserts. The resulting
plastic bicycle would look very different, especially if the frame was
molded or vacuum formed. For example:
https://bikerumor.com/2015/12/28/the-placha-plastic-concept-bike/
https://inhabitat.com/colorful-frii-concept-bike-is-built-from-injection-molded-recycled-plastic/
http://www.yankodesign.com/2014/12/03/print-on-demand-bicycle/
http://www.yankodesign.com/2009/03/27/foldable-bicycles-how-real-today/
http://www.yankodesign.com/2008/10/20/a-new-way-to-bike/
http://www.yankodesign.com/2008/03/21/one-seriously-tight-light-bike/
http://www.yankodesign.com/2010/09/24/15-amazing-bicycles-for-the-future-of-seoul/
etc. Soon, everyone will be riding on mass produced plastic bicycles.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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  #12  
Old May 19th 18, 05:23 PM posted to rec.bicycles.tech
AMuzi
external usenet poster
 
Posts: 9,635
Default may or may not be 'tech'

On 5/19/2018 11:02 AM, Jeff Liebermann wrote:
On Sat, 19 May 2018 07:40:08 -0500, AMuzi wrote:

On 5/19/2018 2:34 AM, Jeff Liebermann wrote:
On Fri, 18 May 2018 20:02:04 -0500, AMuzi wrote:

Go though the linked brochure images. It's amateurish IMHO.

I didn't see a link to a brochure.

Maybe this is what you're thinking of:
https://books.google.com/books?id=4bSABo8Akh4C&pg=PA105&lpg=PA105#v=onepage &q&f=false
It sure doesn't look like it were made from any form of known plastic.
Oh, now I see why:
"Although this prototype had many steel parts, final
model is scheduled to have plastic frame, forks, handlebars,
gears, chain, hubs, and derailleur. Rim and cranks will
be alloy."
I wanna see the plastic gears in action. In other words, what you see
in the "prototype" photo is nothing even close to what is described,
planned, or expected.


Try this catalog link:
http://www.velo-pages.com/main.php?g2_itemId=27603

notably:
http://www.velo-pages.com/main.php?g2_itemId=27633


http://www.velo-pages.com/main.php?g2_itemId=27633&g2_imageViewsIndex=1
In 1973, we didn't have Photoshop, so the pictures look like they
might have been colorized in a darkroom onto film or paper using color
filters. The sharp edges on the various parts suggest that the parts
were not painted, which would have more rounded edges. The crankset
shows threaded hardware, without metal inserts, which is unlikely to
be the way a plastic crankset would be built. There's also no
indication of any tooth wear, which is what I would expect with a
plastic gear and a steel chain. The parts shown look exactly like the
metal equivalents, which is too much of a coincidence to be
believable. Plastic is much weaker than metal and therefore requires
thicker parts, reinforcing ribs, and metal inserts. The resulting
plastic bicycle would look very different, especially if the frame was
molded or vacuum formed. For example:
https://bikerumor.com/2015/12/28/the-placha-plastic-concept-bike/
https://inhabitat.com/colorful-frii-concept-bike-is-built-from-injection-molded-recycled-plastic/
http://www.yankodesign.com/2014/12/03/print-on-demand-bicycle/
http://www.yankodesign.com/2009/03/27/foldable-bicycles-how-real-today/
http://www.yankodesign.com/2008/10/20/a-new-way-to-bike/
http://www.yankodesign.com/2008/03/21/one-seriously-tight-light-bike/
http://www.yankodesign.com/2010/09/24/15-amazing-bicycles-for-the-future-of-seoul/
etc. Soon, everyone will be riding on mass produced plastic bicycles.



And in your link the Weinmann DiaCompe #144 lever (inset #1)
is distinctive and recognizable, unmodified except for
color. Chain (insert #2) is not polymer. The Cyclo chainring
set below that is a standard part shown colored (paint?
image manipulation?) as is the Atom-Regina freewheel.

I always assumed the top left whatchacallits were non-bike
subterfuges or distractions, one of which sits posed on a
bicycle sprocket as misdirection. I could be wrong.

I agree that polymer materials, forming techniques
(injection or positive layering) and impregnation/inclusion
(Fiberglas, Spectra/Aramid, carbon strands, metal inserts
and so on) are dramatically different from 1973:

https://aviationbenefits.org/case-st...87-dreamliner/

and even:
https://www.youtube.com/watch?v=DoPVe7MiY1w

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


  #13  
Old May 19th 18, 08:08 PM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 2,833
Default may or may not be 'tech'

On Sat, 19 May 2018 11:23:05 -0500, AMuzi wrote:

On 5/19/2018 11:02 AM, Jeff Liebermann wrote:
http://www.velo-pages.com/main.php?g2_itemId=27633&g2_imageViewsIndex=1


And in your link the Weinmann DiaCompe #144 lever (inset #1)
is distinctive and recognizable, unmodified except for
color. Chain (insert #2) is not polymer. The Cyclo chainring
set below that is a standard part shown colored (paint?
image manipulation?) as is the Atom-Regina freewheel.


I'm fairly sure that it's not paint because that added thickness of
one or more layers of paint would tend to round the sharp edges, which
is now what I'm seeing in the photo.

I always assumed the top left whatchacallits were non-bike
subterfuges or distractions, one of which sits posed on a
bicycle sprocket as misdirection. I could be wrong.


Offhand, I would guess(tm) that it's a one way ratchet clutch that
fits inside the red hub. It would make a suitable single speed rear
drive assembly for a bicycle (or a small tank).

I agree that polymer materials, forming techniques
(injection or positive layering) and impregnation/inclusion
(Fiberglas, Spectra/Aramid, carbon strands, metal inserts
and so on) are dramatically different from 1973:

https://aviationbenefits.org/case-st...87-dreamliner/


Sure. When you change the materials used, the sizes, shapes, and
fasteners change with it. Unless the materials have identical
mechanical properties, a building made from wood is quite different
from a similar building made from concrete, mud, hay bales, sod, or
inflatable vinyl. This is especially true of highly optimized
designs, such as bicycles, where proper operation depends on the
adjacent hardware acting in a predictable manner. If the adjacent
hardware changes in some way, then literally every nearby part will
also need to change. Drastic changes, like going from steel to
plastic is going to require some rather radical design changes.

and even:
https://www.youtube.com/watch?v=DoPVe7MiY1w


Been there before, about 65 years ago:
https://www.google.com/search?tbm=isch&q=wwii+liberator+pistol
Besides identical names, there are other similarities, such as self
destruction after a few shots, shoddy construction, poor reliability,
etc. Progress blunders onward.

Whenever I see photos of the ride share fiasco in China, where
thousands (or millions?) of bicycles are literally abandoned on the
streets, I have to ask myself, how did they make those bicycles so
quickly and cheaply?
https://www.google.com/search?q=china+abandoned+bikes&tbm=isch
Probably lots of plastic parts.



--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #14  
Old May 19th 18, 08:22 PM posted to rec.bicycles.tech
AMuzi
external usenet poster
 
Posts: 9,635
Default may or may not be 'tech'

On 5/19/2018 2:08 PM, Jeff Liebermann wrote:
On Sat, 19 May 2018 11:23:05 -0500, AMuzi wrote:

On 5/19/2018 11:02 AM, Jeff Liebermann wrote:
http://www.velo-pages.com/main.php?g2_itemId=27633&g2_imageViewsIndex=1


-snip snip-

Whenever I see photos of the ride share fiasco in China, where
thousands (or millions?) of bicycles are literally abandoned on the
streets, I have to ask myself, how did they make those bicycles so
quickly and cheaply?
https://www.google.com/search?q=china+abandoned+bikes&tbm=isch
Probably lots of plastic parts.



Good query and I don't know.

I suspect that for a bicycle manufacturer on a contract for
10, 20, 50, 100,000 bicycles, assembling from mostly
standard parts (which are dirt cheap) is the logical path.
At some larger run injection molds might pay off but I don't
know that would always be true.

For a specific injection molded part I paid $3000 for a tool
in The Middle Kingdom but to replace it in Wisconsin USA
cost $11,000. So there's that. For a run of bicycles with
as you wrote, 'lots of plastic parts' you're talking 'lots
of tools' besides the amortization for each tool.

OTOH if you meant Tourney level mostly nylon gear changers
and shifters as opposed to Deore type mostly aluminum parts,
then I absolutely agree.

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


  #15  
Old May 21st 18, 02:40 AM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 2,833
Default may or may not be 'tech'

On Sat, 19 May 2018 14:22:52 -0500, AMuzi wrote:

On 5/19/2018 2:08 PM, Jeff Liebermann wrote:
On Sat, 19 May 2018 11:23:05 -0500, AMuzi wrote:

On 5/19/2018 11:02 AM, Jeff Liebermann wrote:
http://www.velo-pages.com/main.php?g2_itemId=27633&g2_imageViewsIndex=1


-snip snip-

Whenever I see photos of the ride share fiasco in China, where
thousands (or millions?) of bicycles are literally abandoned on the
streets, I have to ask myself, how did they make those bicycles so
quickly and cheaply?
https://www.google.com/search?q=china+abandoned+bikes&tbm=isch
Probably lots of plastic parts.


Good query and I don't know.

I suspect that for a bicycle manufacturer on a contract for
10, 20, 50, 100,000 bicycles, assembling from mostly
standard parts (which are dirt cheap) is the logical path.
At some larger run injection molds might pay off but I don't
know that would always be true.

For a specific injection molded part I paid $3000 for a tool
in The Middle Kingdom but to replace it in Wisconsin USA
cost $11,000. So there's that. For a run of bicycles with
as you wrote, 'lots of plastic parts' you're talking 'lots
of tools' besides the amortization for each tool.


Would $600 million dollars suffice to pay for the necessary molds and
tooling?
https://techcrunch.com/2017/06/15/mobike-raises-600-million/
That's in addition to $300 million Mobike raised from investors.

Notice the wheels on the Mobike bicycles in the photos.
https://techcrunch.com/wp-content/uploads/2017/06/mobikes-airless-tyres.jpg
Plastic rims on the bicycles some of the bicycles, while conventional
spokes and aluminum(?) rims on others. My guess(tm) is they're
replacing older higher cost technology with better and cheaper. In
large quantities, that means stamped or molded parts replacing
extruded and assembled parts.

Many of the frames look very different and are not a conventional
geometry. They seem to be designed to be rugged, easy to fabricate,
and built to be stored outdoors, all possibly at the expense of
weight.
https://media.wired.com/photos/5a84ad90a2d3835392e1b58a/master/w_582,c_limit/Limebike-TopArt.jpg
More like a "comfort bike" than a cheapened conventional bicycle. With
a "one size fits all" design and sizing, variations in frame
construction by size can be ignored resulting in even larger
production quantities using hydroforming and robotic welding.

I haven't seen one of these bikeshare bikes up close, so I'm doing
quite a bit of guessing. I may get my chance shortly as the People's
Republic of Santa Cruz now has a bikeshare program:
http://www.cityofsantacruz.com/government/city-departments/public-works/traffic-engineering/bike-share

OTOH if you meant Tourney level mostly nylon gear changers
and shifters as opposed to Deore type mostly aluminum parts,
then I absolutely agree.


Where nylon parts can't be used, I suspect that stamped steel seat
posts, cranksets, crank arms, and pedals may make a comeback simply
because they are cheaper.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #16  
Old May 21st 18, 03:29 AM posted to rec.bicycles.tech
John B.[_3_]
external usenet poster
 
Posts: 3,967
Default may or may not be 'tech'

On Sun, 20 May 2018 18:40:27 -0700, Jeff Liebermann
wrote:

On Sat, 19 May 2018 14:22:52 -0500, AMuzi wrote:

On 5/19/2018 2:08 PM, Jeff Liebermann wrote:
On Sat, 19 May 2018 11:23:05 -0500, AMuzi wrote:

On 5/19/2018 11:02 AM, Jeff Liebermann wrote:
http://www.velo-pages.com/main.php?g2_itemId=27633&g2_imageViewsIndex=1


-snip snip-

Whenever I see photos of the ride share fiasco in China, where
thousands (or millions?) of bicycles are literally abandoned on the
streets, I have to ask myself, how did they make those bicycles so
quickly and cheaply?
https://www.google.com/search?q=china+abandoned+bikes&tbm=isch
Probably lots of plastic parts.


Good query and I don't know.

I suspect that for a bicycle manufacturer on a contract for
10, 20, 50, 100,000 bicycles, assembling from mostly
standard parts (which are dirt cheap) is the logical path.
At some larger run injection molds might pay off but I don't
know that would always be true.

For a specific injection molded part I paid $3000 for a tool
in The Middle Kingdom but to replace it in Wisconsin USA
cost $11,000. So there's that. For a run of bicycles with
as you wrote, 'lots of plastic parts' you're talking 'lots
of tools' besides the amortization for each tool.


Would $600 million dollars suffice to pay for the necessary molds and
tooling?
https://techcrunch.com/2017/06/15/mobike-raises-600-million/
That's in addition to $300 million Mobike raised from investors.

Notice the wheels on the Mobike bicycles in the photos.
https://techcrunch.com/wp-content/uploads/2017/06/mobikes-airless-tyres.jpg
Plastic rims on the bicycles some of the bicycles, while conventional
spokes and aluminum(?) rims on others. My guess(tm) is they're
replacing older higher cost technology with better and cheaper. In
large quantities, that means stamped or molded parts replacing
extruded and assembled parts.

Many of the frames look very different and are not a conventional
geometry. They seem to be designed to be rugged, easy to fabricate,
and built to be stored outdoors, all possibly at the expense of
weight.
https://media.wired.com/photos/5a84ad90a2d3835392e1b58a/master/w_582,c_limit/Limebike-TopArt.jpg
More like a "comfort bike" than a cheapened conventional bicycle. With
a "one size fits all" design and sizing, variations in frame
construction by size can be ignored resulting in even larger
production quantities using hydroforming and robotic welding.

I haven't seen one of these bikeshare bikes up close, so I'm doing
quite a bit of guessing. I may get my chance shortly as the People's
Republic of Santa Cruz now has a bikeshare program:
http://www.cityofsantacruz.com/government/city-departments/public-works/traffic-engineering/bike-share

OTOH if you meant Tourney level mostly nylon gear changers
and shifters as opposed to Deore type mostly aluminum parts,
then I absolutely agree.


Where nylon parts can't be used, I suspect that stamped steel seat
posts, cranksets, crank arms, and pedals may make a comeback simply
because they are cheaper.


A couple of years ago I was at a Bike show where quite a number of
Mainland Chinese manufacturers were present. I asked one of the
vendors what he'd have to charge for a complete Head Bearing Set.
After some discussion about size of order, etc., the guy reckoned that
for a smallish order the cost would be 1 dollar each.

Or look at Alibaba volume prices and then think what they would be
when you said, "Oh say, 50,000 units"?

--
Cheers,

John B.

  #17  
Old May 21st 18, 04:49 AM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 2,833
Default may or may not be 'tech'

On Sun, 20 May 2018 18:40:27 -0700, Jeff Liebermann
wrote:

Many of the frames look very different and are not a conventional
geometry. They seem to be designed to be rugged, easy to fabricate,
and built to be stored outdoors, all possibly at the expense of
weight.


Definitely at the expense of weight. Only 42.5 lbs (19.3kg):
https://bikesiliconvalley.org/wp-content/uploads/styles/large/public/images/BABS-bike-diagram.png
Kinda looks like the down tube and rear fender were designed to act as
advertising billboards.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #18  
Old May 21st 18, 05:53 AM posted to rec.bicycles.tech
ERSHC
external usenet poster
 
Posts: 30
Default may or may not be 'tech'

On Fri, 18 May 2018 20:02:04 -0500, AMuzi wrote:
On 5/18/2018 5:13 PM, ERSHC wrote:
On Fri, 18 May 2018 13:44:19 -0500, AMuzi wrote:

Which is unrelated, those being actual products. The
Original Plastic Bike, Inc was only a brochure with slick
photo production but there was no actual product.

OPB may never have sold a bike, but they had at least one store front,
so were (slightly) more than "only a brochure". This was probably
summer of 1972. I was working in a bike shop in Rocky Point, NY (on
Long Island). OPB opened a store in a strip mall a few miles away (on
25A, maybe in Miller Place?) that was closed by the end of the summer.


Did you ever go in? I ask because the brochure showed
relatively pedestrian bike parts (some recognizable by
brand/model) with glossy polyurethane paint in bold colors.
Nothing about the presentation would have fooled an
experienced mechanic, engineer or injection mold specialist.
There was no serious attempt to disguise metal objects
which, by their shape, could not possibly be executed
successfully in polymers.


I never got in, and I don't recall seeing a bike. The one time I
stopped by, the place was already closed. I think my boss at the time
stopped in (or somehow saw the bikes) because I do recall a customer
asking about them and him replying that they didn't (yet?) have chains
and all the parts were "non-standard".


Apparently the brochure was 'good enough' to swindle some
number of investors.

Go though the linked brochure images. It's amateurish IMHO.

 




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