On 12/28/2018 7:46 PM, Frank Krygowski wrote:
On 12/28/2018 7:35 PM, AMuzi wrote:
On 12/28/2018 6:00 PM, John B. Slocomb wrote:
On Fri, 28 Dec 2018 14:41:12 -0800 (PST),
wrote:
On Wednesday, December 26, 2018 at 4:22:08 PM UTC-8,
John B. Slocomb wrote:
On Wed, 26 Dec 2018 12:02:58 -0800 (PST),
wrote:
On Thursday, November 29, 2018 at 1:25:28 PM UTC-8,
Sir Ridesalot wrote:
An interesting video of track bicycles crashing.
Amazing what happens when a tubular tire comes off
the rim. I was surprised at how long one rider stayed
up - he was okay until the front tire went under his
rear wheel.
I saw bits flying around in some of the crashes but
couldn't make out what those bits were.
https://www.youtube.com/watch?v=tf17hFikqrQ
Cheers
Track tubulars are paper thin so flats from
overheating aren't all that uncommon. My friend who
has turned into a total anti-carbon fiber nut sent me
a video link to a subject he called "carbon fiber rim
exploding under track rider." That isn't what I would
have called it. If you look at it closely it looks
like a track tandem gets a flat in the final sprint
which throws the entire weight of the team unto the
front disk which slowly comes apart as the tire peels
off.
I showed him that foregoing manufacturing errors that
all of the bicycle materials have approximately the
same loaded lifespan. That was sort of surprising to
me since I have a lot of steel bikes and never had a
failure. But I suppose I usually buy them with very
little use and they simply don't have that many miles.
Actually the most common frame material to fail is
aluminum. Come sources say never keep an aluminum
frame for more than 10 years max. And the failures are
highly reminiscent of the Internet pictures of carbon
fiber failures save that the CF bikes usually have
been hit by cars whereas the AL bikes simply fall apart.
Interesting.
Of course Sheldon Brown, that sneaky devil, describes a
study
conducted by EFBe (Engineering for Bikes) which is now,
I believe, one
of the main elements of the DIN 79100 bicycle-testing
standard, which
was published in TOUR magazine of Oct 1997 ( more then
20 years ago)
that demonstrated that two of the three frames that
completed the test
with no failures were welded aluminum frames. Two out
of three... lets
see, that is about 66.666 %, isn't it?
The Christian Bible has a phrase that seems to apply
here (Proverbs
17:28. New International Version)
"Even a fool is thought wise if he keeps silent, and
discerning if he
holds his tongue."
cheers,
John B.
Of course anyone with any training would understand that
this testing meant nothing. While the test itself was
well designed using a single example of each frame
yielded no more information that THAT single example.
But then you're the sort of engineer who would build a
bridge without actually testing the components of it.
I see... first you condemn a test to failure as it tests
only one
example and then you refer to testing bridge components.
Tom, you are a fool. Or do you actually believe that each
component of
a bridge is tested to failure... before it is used?
I worked for a company that specialized in contacting with
international oil companies to build and.or maintain oil
fields in
remote areas and in doing so we built innumerable bridges
and I'm
sorry to inform you that we never tested the components
of any of the
bridges... never. And I can assure you that none of the
bridges ever
fell down.
I might add, that as we were in business for over 20
years, and as oil
companies were still giving us contacts it is patently
obvious that we
knew what we were doing as oil companies don't renew
contacts to
companies that build bridges that fall down.
I keep telling you, "It's better to keep your mouth shut
and appear
stupid than open it and remove all doubt" and you don't
listen.
Indonesia may have some regard for human life and
engineering standards. Not everyone does:
https://am1590theanswer.com/news/nat...10-years-later
"...federal funding has been 'pretty stagnant,' but about 20
states raised taxes to increase their bridge spending."
Where are the "No new taxes" guys?
[raises hand] Over here! And ditch old ones as well!
The bridge was built with the wrong plates _and_ it passed
inspection. This is not a 'funding' problem except insofar
as public monies seem to attract corruption generally.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971