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post #61 of 89

Re: Dumb question #3 - counting gears

Frank Krygowski writes:

>>> My point is: every sport has accumulated generations of wisdom,
>>> which came from generations of trial and error. And people have
>>> known for at least 100 years that spinning bike cranks at, say, 80
>>> to 100 rpm works better in the long run. That is, you'll be able
>>> to ride faster and further on any given ride, and you're knees
>>> will probably last longer.


>> Where do you get this stuff?


> ??


> _Richard's 21st Century Bicycle Book_, by Richard Ballantine.


> _Effective Cycling_ by John Forester


> _Cycling for Fitness_ by John Schubert


> _The Woman Cyclist_ by Elaine Mariolle


> etc, etc, etc. It would take me all evening to give you all the sources
> on my bookshelf that agree with what I've said.


> So, where do you find sources that disagree?


As I stated, from aerodynamic calculations inspired by observations in
years of riding with believers in the power of huge gears. Typically
John Howard's gear on his land speed record that was so high he could
not propel the bicycle at all with it unless he was in the vortex of
the race car on the salt flats. He had to be pulled up to speed to
even turn the pedals.

At least two of the works you cite are written by rave charlatans. I
have testified against them as expert witness in court cases in which
plaintiffs made irrational claims and to which they gave support with
pseudo science.

"Defective Cycling" is a great one for half truths and misleading
"facts". John Howard pandered to the plaintiffs claims as well
brining us "lawyer lips" long before the disk brake fiasco made them
somewhat useful.

Jobst Brandt
jobst.brandt@stanfordalumni.org
post #62 of 89

Re: Dumb question #3 - counting gears

jobst.brandt@stanfordalumni.org wrote:

> Frank Krygowski writes:
>
>
>
>>_Richard's 21st Century Bicycle Book_, by Richard Ballantine.

>
>
>>_Effective Cycling_ by John Forester

>
>
>>_Cycling for Fitness_ by John Schubert

>
>
>>_The Woman Cyclist_ by Elaine Mariolle

>
>
>>etc, etc, etc. It would take me all evening to give you all the sources
>>on my bookshelf that agree with what I've said.

>
>
>>So, where do you find sources that disagree?

>
>
> As I stated, from aerodynamic calculations inspired by observations in
> years of riding with believers in the power of huge gears.


This thread has subdivided into two topics.

One regards the uselessness of super-high gears on steep descents. On
that you and I agree.

The other regards optimum cadence for putting out power for long periods
of time. The sources listed above talk about that issue, not the first one.

>
> At least two of the works you cite are written by rave charlatans.


The world would be simpler if "rave charlatans" (or those disparaged as
such) were _never_ correct, and if people who weren't called
"charlatans" were never wrong. But the world is simply not that way!

> I
> have testified against them as expert witness in court cases in which
> plaintiffs made irrational claims and to which they gave support with
> pseudo science.


.... and the world would be simpler if people didn't demonize those who
have been their opponents. But, sadly, the world isn't that way either.

http://www.nizkor.org/features/fallacies/ would make good reading
before we return to actually discussing facts.


>
> "Defective Cycling" is a great one for half truths and misleading
> "facts".


I do not agree with every word in that book. However, most of it is
definitely correct, in my experience.


John Howard pandered to the plaintiffs claims as well
> brining us "lawyer lips" long before the disk brake fiasco made them
> somewhat useful.


My guess is you're confusing John Howard (who is not mentioned above)
with John Schubert (who is). They are not the same person.


--
--------------------+
Frank Krygowski [To reply, remove rodent and vegetable dot com,
replace with cc.ysu dot edu]
post #63 of 89

Re: Dumb question #3 - counting gears

On Sun, 15 Aug 2004 14:28:21 GMT, <jobst.brandt@stanfordalumni.org> wrote:

> Frank Krygowski writes:
>
> As I stated, from aerodynamic calculations inspired by observations in
> years of riding with believers in the power of huge gears. Typically
> John Howard's gear on his land speed record that was so high he could
> not propel the bicycle at all with it unless he was in the vortex of
> the race car on the salt flats. He had to be pulled up to speed to
> even turn the pedals.
>
> Jobst Brandt
> jobst.brandt@stanfordalumni.org

I don't know that it was John Howard, but I read years ago about a
fellow doing 105 MPH behind a train that had been rigged with a
special aero shield/tunnel on the trailing car. The tracks were also
paved between the rails so a bike could ride on it. The article
mentioned that his front chainring was so large that if he angled
the bicycle over just a few degrees it would hit the ground. This
was, as far as I can remember something that I read about when I was
very young, so it was probably back in the 50s or early 60s. The
magazine may have been Popular Science or Popular Mechanics since I
read those from about second grade on up. If Howard did over 105
then I have to give him credit for pushing the salt, if not, then
he does not have the real record. Just don't ask me to quote the
exact issue since it was over 40 years ago.
Bill Baka


--
Using M2, Opera's revolutionary e-mail client: http://www.opera.com/m2/
post #64 of 89

Re: Dumb question #3 - counting gears

Peter Cole <peter_cole_no_spam_at_all@comcast.net> wrote:
>But, if you & I were riding at the same speed, you in your 50x13 and me in my
>53x11, the only difference would be our cadence.


He's spinning at 84 rpm and you're mashing at 67. You're
both doing 26 mph. You're both putting out the same amount
of power. But you're holding a higher force over a longer
time in each stroke. If you're lifting weight, the heavier
weight can make you train to exhaustion within a few reps,
while you might push a much lighter one at a higher rate
essentially all day.

And if you're not 25% stronger in the first place, you're
going to have to stand up to maintain that cadence.

So, the significant difference would be that your thighs
would be about 6 inches bigger from all the mashing you'd
have to do to keep up on your daily ride.

>By saying people have no need
>for such a ratio, you're just saying your cadence is the "right" one for
>everybody.


Is 67 rpm right for anyone who isn't scanning the shoulder
for aluminum cans?

>I think you'd have to admit that there is a variation as to what
>cadence (range) is preferred, and the difference between a 50x13 and 53x11
>might simply reflect that preference.


I think the difference is bigger than that, and appears on the
descents, where such gears as 53/11 actually make some sense and
a 50/13 get useless in a hurry.

--Blair
"Wait. What kind of chain lube are
you using?"
post #65 of 89

Re: Dumb question #3 - counting gears

Frank Krygowski writes:

>> "Defective Cycling" is a great one for half truths and misleading
>> "facts".


> I do not agree with every word in that book. However, most of it is
> definitely correct, in my experience.



>> John Howard pandered to the plaintiffs claims as well brining us
>> "lawyer lips" long before the disk brake fiasco made them somewhat
>> useful.


> My guess is you're confusing John Howard (who is not mentioned above)
> with John Schubert (who is). They are not the same person.


Not at all. John Howard testified in a case where a rider claimed he
had properly closed a QR and that the wheel came out after he had
ridden some insignificant distance. John Howard testified that as a
professional racer he was aware the QR's work loose and the the claim
of the plaintiff was valid. The result at that time were lawyer lips
on dropouts of less expensive bicycles. Only later when wheel
separations occurred on MTB's with disk brakes did these devices
become common and meaningful. Road racers still want to drop a wheel
out fast and install a replacement one without these retention ridges
and they do so.

Besides, when I see an expert witness outright lie in a law suit, it
destroys his credibility altogether for me. "I was lying then, but
now I'm telling the truth." What can you believe? I get involved in
these cases only when I see grave harm being done to the bicycle
business, be that a retail shop or a major manufacturer. The retail
shop is the cruelest one where there is no deep pockets and insurance,
if it must pay, will often pull the plug or raise the premium beyond
what the shop can afford.

Jobst Brandt
jobst.brandt@stanfordalumni.org
post #66 of 89

Re: Dumb question #3 - counting gears

Bill Baka writes:

>> As I stated, from aerodynamic calculations inspired by observations
>> in years of riding with believers in the power of huge gears.
>> Typically John Howard's gear on his land speed record that was so
>> high he could not propel the bicycle at all with it unless he was
>> in the vortex of the race car on the salt flats. He had to be
>> pulled up to speed to even turn the pedals.


http://www.newuniquevideos.com/DISTR...hn_howard.html

In fact his contribution to propulsion was so small that throttle
control was given to Howard on the bicycle so he could remain in the
vortex, the car driver not having enough control to maintain contact.

> I don't know that it was John Howard, but I read years ago about a
> fellow doing 105 MPH behind a train that had been rigged with a
> special aero shield/tunnel on the trailing car. The tracks were also
> paved between the rails so a bike could ride on it. The article
> mentioned that his front chainring was so large that if he angled
> the bicycle over just a few degrees it would hit the ground. This
> was, as far as I can remember something that I read about when I was
> very young, so it was probably back in the 50s or early 60s. The
> magazine may have been Popular Science or Popular Mechanics since I
> read those from about second grade on up. If Howard did over 105
> then I have to give him credit for pushing the salt, if not, then he
> does not have the real record. Just don't ask me to quote the exact
> issue since it was over 40 years ago.


You are thinking of "Mile a minute Murphy" who was famous for his
feat. It was repeated by others, the area between the rails having a
board track installed. These guys were mainly entertainment and knew
how to please an unwitting crowd. That riding at those speeds without
special streamlining was not possible, did not occur to folks.

http://www.newsday.com/extras/lihist...lt/lirrsky.htm

The shape of the wind screen had the effect that is common in
convertible cars where hair is blown forward into the passenger's face
by wind curling around the wind screen. I suspect it was just such an
observation that led to these "record" runs.

To me, the interesting records are those achieved with human power
only in the HPVA (Human Powered Vehicle Assn.)

http://www.wisil.recumbents.com/wisi...tsSaturday.htm

Jobst Brandt
jobst.brandt@stanfordalumni.org
post #67 of 89

Re: Dumb question #3 - counting gears

On 16 Aug 2004 04:03:52 GMT, R15757 <r15757@aol.com> wrote:

> Bill Baka wrote:
>
> << I don't know that it was John Howard, but I read years ago about a
> fellow doing 105 MPH behind a train that had been rigged with a
> special aero shield/tunnel on the trailing car. The tracks were also
> paved between the rails so a bike could ride on it. The article
> mentioned that his front chainring was so large that if he angled
> the bicycle over just a few degrees it would hit the ground. This
> was, as far as I can remember something that I read about when I was
> very young, so it was probably back in the 50s or early 60s. The
> magazine may have been Popular Science or Popular Mechanics since I
> read those from about second grade on up. If Howard did over 105
> then I have to give him credit for pushing the salt, if not, then
> he does not have the real record. Just don't ask me to quote the
> exact issue since it was over 40 years ago.>>
>
>
> Charlie Murphy rode a mile in under 58 seconds
> in 1899, behind a train on Long Island. He probably
> reached 70 mph at some point. He reported
> being burned by cinders and said the planks
> laid down between the tracks were undulating
> wildly as the train passed over them. At the end
> of the run, he crashed heavily into the back
> of the train.
>
> Robert
>

That was not the incident. It was a diesel and he hit 105, not just 70
Bill Baka


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post #68 of 89

Re: Dumb question #3 - counting gears

On Sun, 15 Aug 2004 23:39:36 -0700, Bernie <bmcilvan@mouse-potato.com>
wrote:

> R15757 wrote:
>
>> Bill Baka wrote:
>>
>> << I don't know that it was John Howard, but I read years ago about a
>> fellow doing 105 MPH behind a train that had been rigged with a
>> special aero shield/tunnel on the trailing car. The tracks were also
>> paved between the rails so a bike could ride on it. The article
>> mentioned that his front chainring was so large that if he angled
>> the bicycle over just a few degrees it would hit the ground. This
>> was, as far as I can remember something that I read about when I was
>> very young, so it was probably back in the 50s or early 60s. The
>> magazine may have been Popular Science or Popular Mechanics since I
>> read those from about second grade on up. If Howard did over 105
>> then I have to give him credit for pushing the salt, if not, then
>> he does not have the real record. Just don't ask me to quote the
>> exact issue since it was over 40 years ago.>>
>>
>>
>> Charlie Murphy rode a mile in under 58 seconds
>> in 1899, behind a train on Long Island. He probably reached 70 mph at
>> some point. He reported
>> being burned by cinders and said the planks
>> laid down between the tracks were undulating wildly as the train passed
>> over them. At the end
>> of the run, he crashed heavily into the back
>> of the train.
>>
>> Robert
>>
>>

> I read this mind blowing story a couple of years ago about "MILE A
> MINUTE MURPHY". He had an exciting adventure, and proved himself right
> in the process:
>
> http://www.newsday.com/extras/lihist...lt/lirrsky.htm
>
> Best regards, Bernie
>

Again, 105 MPH wan not Murphy.
Bill Baka


--
Using M2, Opera's revolutionary e-mail client: http://www.opera.com/m2/
post #69 of 89

Re: Dumb question #3 - counting gears

On Mon, 16 Aug 2004 07:15:05 GMT, <jobst.brandt@stanfordalumni.org> wrote:

> Bill Baka writes:
>
>>> As I stated, from aerodynamic calculations inspired by observations
>>> in years of riding with believers in the power of huge gears.
>>> Typically John Howard's gear on his land speed record that was so
>>> high he could not propel the bicycle at all with it unless he was
>>> in the vortex of the race car on the salt flats. He had to be
>>> pulled up to speed to even turn the pedals.

>
> http://www.newuniquevideos.com/DISTR...hn_howard.html
>
> In fact his contribution to propulsion was so small that throttle
> control was given to Howard on the bicycle so he could remain in the
> vortex, the car driver not having enough control to maintain contact.
>
>> I don't know that it was John Howard, but I read years ago about a
>> fellow doing 105 MPH behind a train that had been rigged with a
>> special aero shield/tunnel on the trailing car. The tracks were also
>> paved between the rails so a bike could ride on it. The article
>> mentioned that his front chainring was so large that if he angled
>> the bicycle over just a few degrees it would hit the ground. This
>> was, as far as I can remember something that I read about when I was
>> very young, so it was probably back in the 50s or early 60s. The
>> magazine may have been Popular Science or Popular Mechanics since I
>> read those from about second grade on up. If Howard did over 105
>> then I have to give him credit for pushing the salt, if not, then he
>> does not have the real record. Just don't ask me to quote the exact
>> issue since it was over 40 years ago.

>
> You are thinking of "Mile a minute Murphy" who was famous for his
> feat. It was repeated by others, the area between the rails having a
> board track installed. These guys were mainly entertainment and knew
> how to please an unwitting crowd. That riding at those speeds without
> special streamlining was not possible, did not occur to folks.
>
> http://www.newsday.com/extras/lihist...lt/lirrsky.htm
>
> The shape of the wind screen had the effect that is common in
> convertible cars where hair is blown forward into the passenger's face
> by wind curling around the wind screen. I suspect it was just such an
> observation that led to these "record" runs.
>
> To me, the interesting records are those achieved with human power
> only in the HPVA (Human Powered Vehicle Assn.)
>
> http://www.wisil.recumbents.com/wisi...tsSaturday.htm
>
> Jobst Brandt
> jobst.brandt@stanfordalumni.org


Quite simply I will now have to find the article that says a fellow
did 105 MPH behind a train, and not on the salt flats.
Bill Baka


--
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post #70 of 89

Re: Dumb question #3 - counting gears

"Blair P. Houghton" <b@p.h> wrote in message
news:T7XTc.21857504$Of.3642082@news.easynews.com...
> Peter Cole <peter_cole_no_spam_at_all@comcast.net> wrote:
> >But, if you & I were riding at the same speed, you in your 50x13 and me in

my
> >53x11, the only difference would be our cadence.

>
> He's spinning at 84 rpm and you're mashing at 67. You're
> both doing 26 mph. You're both putting out the same amount
> of power. But you're holding a higher force over a longer
> time in each stroke. If you're lifting weight, the heavier
> weight can make you train to exhaustion within a few reps,
> while you might push a much lighter one at a higher rate
> essentially all day.


Yes, and if I'm riding all day, I'd likely use a higher cadence. The faster
cadence will generally delay muscle fatigue to an extent, but for short, fast
rides (1-2 hr), the lower cadence will support higher speeds because of
aerobic efficiency, it's a tradeoff. I don't usually switch cassettes for
rides, so I use a wide (11-28) to be able to use high gears on short rides and
still have very low gears for all day climbing in ultra events.

It's obvious from physics that there's a diminishing return from pedaling at
high speeds, and that more can be obtained from a good tuck than pedaling on a
reasonably steep descent. I'd say the highest gear you need is the one your
most comfortable with under your highest speed pedaling scenarios, for me,
that's a 53x11.
post #71 of 89

Re: Dumb question #3 - counting gears

On Sun, 15 Aug 2004 11:34:54 -0700, Bill Baka <bbaka@syix.com> wrote:

>I don't know that it was John Howard, but I read years ago about a
>fellow doing 105 MPH behind a train that had been rigged with a
>special aero shield/tunnel on the trailing car. The tracks were also
>paved between the rails so a bike could ride on it. The article
>mentioned that his front chainring was so large that if he angled
>the bicycle over just a few degrees it would hit the ground.


I think you are confusing two different events. Alfred Letourner was
the one that jumped the paced land speed record to the 105 mph range
(actually, over 108) behind a car. His first attempt ended in a
horrible crash and he either literally or figuratively lived like a
monk (can't remember the exact story) in the process of rebuilding his
body. His paced record was behind a car in the 1940s.

His was also a huge gear and is probably the one that would have a
problem with tilting the bike, although 'a few degrees' seems
unlikely, more like hyperbole.

The rest sounds like what the others have said, Mile-a-Minute Murphy.

Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
post #72 of 89

Re: Dumb question #3 - counting gears

On Sun, 15 Aug 2004 11:34:54 -0700, Bill Baka <bbaka@syix.com> wrote:

>I don't know that it was John Howard, but I read years ago about a
>fellow doing 105 MPH behind a train that had been rigged with a
>special aero shield/tunnel on the trailing car. The tracks were also
>paved between the rails so a bike could ride on it. The article
>mentioned that his front chainring was so large that if he angled
>the bicycle over just a few degrees it would hit the ground.


I think you are confusing two different events. Alfred Letourner was
the one that jumped the paced land speed record to the 105 mph range
(actually, over 108) behind a car. His first attempt ended in a
horrible crash and he either literally or figuratively lived like a
monk (can't remember the exact story) in the process of rebuilding his
body. His paced record was behind a car in the 1940s.

His was also a huge gear and is probably the one that would have a
problem with tilting the bike, although 'a few degrees' seems
unlikely, more like hyperbole.

The rest sounds like what the others have said, Mile-a-Minute Murphy.

Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
post #73 of 89

Re: Dumb question #3 - counting gears

On Mon, 16 Aug 2004 10:09:24 -0400, Curtis L. Russell
<curtis@the-md-russells.org> wrote:

> On Sun, 15 Aug 2004 11:34:54 -0700, Bill Baka <bbaka@syix.com> wrote:
>
>> I don't know that it was John Howard, but I read years ago about a
>> fellow doing 105 MPH behind a train that had been rigged with a
>> special aero shield/tunnel on the trailing car. The tracks were also
>> paved between the rails so a bike could ride on it. The article
>> mentioned that his front chainring was so large that if he angled
>> the bicycle over just a few degrees it would hit the ground.

>
> I think you are confusing two different events. Alfred Letourner was
> the one that jumped the paced land speed record to the 105 mph range
> (actually, over 108) behind a car. His first attempt ended in a
> horrible crash and he either literally or figuratively lived like a
> monk (can't remember the exact story) in the process of rebuilding his
> body. His paced record was behind a car in the 1940s.
>
> His was also a huge gear and is probably the one that would have a
> problem with tilting the bike, although 'a few degrees' seems
> unlikely, more like hyperbole.
>
> The rest sounds like what the others have said, Mile-a-Minute Murphy.
>
> Curtis L. Russell
> Odenton, MD (USA)
> Just someone on two wheels...


Remember I am trying to go on 40+ year old memories. I do remember
the mark at 105 (+/-) though, train or car.
Bill Baka


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post #74 of 89

Re: Dumb question #3 - counting gears

jobst.brandt@stanfordalumni.org wrote:

> Frank Krygowski writes:
>
>
>>>"Defective Cycling" is a great one for half truths and misleading
>>>"facts".

>
>
>>I do not agree with every word in that book. However, most of it is
>>definitely correct, in my experience.

>
>
>
>>>John Howard pandered to the plaintiffs claims as well brining us
>>>"lawyer lips" long before the disk brake fiasco made them somewhat
>>>useful.

>
>
>>My guess is you're confusing John Howard (who is not mentioned above)
>>with John Schubert (who is). They are not the same person.

>
>
> Not at all. John Howard testified in a case where a rider claimed he
> had properly closed a QR and that the wheel came out after he had
> ridden some insignificant distance. John Howard testified that as a
> professional racer he was aware the QR's work loose and the the claim
> of the plaintiff was valid. The result at that time were lawyer lips
> on dropouts of less expensive bicycles. Only later when wheel
> separations occurred on MTB's with disk brakes did these devices
> become common and meaningful. Road racers still want to drop a wheel
> out fast and install a replacement one without these retention ridges
> and they do so.
>
> Besides, when I see an expert witness outright lie in a law suit, it
> destroys his credibility altogether for me. "I was lying then, but
> now I'm telling the truth." What can you believe? I get involved in
> these cases only when I see grave harm being done to the bicycle
> business, be that a retail shop or a major manufacturer. The retail
> shop is the cruelest one where there is no deep pockets and insurance,
> if it must pay, will often pull the plug or raise the premium beyond
> what the shop can afford.


I understand. And, FWIW, I wouldn't trust John Howard on anything but,
perhaps, advice on building a world-record motor pacing bike - even
though it's not impossible for such a person to give valid advice on
other matters.

What I meant, though, was that the list of sources I cited did not
include John Howard.


--
--------------------+
Frank Krygowski [To reply, remove rodent and vegetable dot com,
replace with cc.ysu dot edu]
post #75 of 89

Re: Dumb question #3 - counting gears

Frank Krygowski writes:

>>>> "Defective Cycling" is a great one for half truths and misleading
>>>> "facts".


>>> I do not agree with every word in that book. However, most of it is
>>> definitely correct, in my experience.


>>>> John Howard pandered to the plaintiffs claims as well brining us
>>>> "lawyer lips" long before the disk brake fiasco made them somewhat
>>>> useful.


>>> My guess is you're confusing John Howard (who is not mentioned
>>> above) with John Schubert (who is). They are not the same person.


>> Not at all. John Howard testified in a case where a rider claimed he
>> had properly closed a QR and that the wheel came out after he had
>> ridden some insignificant distance. John Howard testified that as a
>> professional racer he was aware the QR's work loose and the the claim
>> of the plaintiff was valid. The result at that time were lawyer lips
>> on dropouts of less expensive bicycles. Only later when wheel
>> separations occurred on MTB's with disk brakes did these devices
>> become common and meaningful. Road racers still want to drop a wheel
>> out fast and install a replacement one without these retention ridges
>> and they do so.


>> Besides, when I see an expert witness outright lie in a law suit, it
>> destroys his credibility altogether for me. "I was lying then, but
>> now I'm telling the truth." What can you believe? I get involved in
>> these cases only when I see grave harm being done to the bicycle
>> business, be that a retail shop or a major manufacturer. The retail
>> shop is the cruelest one where there is no deep pockets and insurance,
>> if it must pay, will often pull the plug or raise the premium beyond
>> what the shop can afford.


> I understand. And, FWIW, I wouldn't trust John Howard on anything
> but, perhaps, advice on building a world-record motor pacing bike -
> even though it's not impossible for such a person to give valid
> advice on other matters.


> What I meant, though, was that the list of sources I cited did not
> include John Howard.


Well I have run into Sloan, Green, and Forester, all testifying to BS
that would fool a jury unless someone explained why their story was
untrue. These were up to million dollar damage claims.

OK, so you need to hear the typical story:

I came across Forester more than once, the most recent time was about
a sponsored MTB racer who made up a **** and bull story how a flat
front tire caused his fall, claiming the flat was caused by a faulty
rim strip that cut the tube. In fact he rode with too low inflation
pressure on a knobby large cross section tire after muddy trails,
descending a paved road where he rolled the tire that did not separate
from the rim.

When such a tire rolls to one side it gets snake bite cuts, not on the
side as though you were to pinch your cheek, but on the underside as
if you were to pinch your adam's apple. Visualize pinching under the
chin and leaning the head to one side as the tire did. This causes
the underside of the tube to get pinched.

The tube was about half the size of the tire volume, so when inflated
it was far larger than deflated. The pinch slits caused by rolling
forward while lying to one side were spaced about as far apart as the
rim strip was wide. Hence a plausible cause to an uninitiated viewer.
What doesn't work is that the tube would have cuts half as far apart
as the width of the tape (if it had been the cause) when inspected
because it shrank to its un-inflated size and would have marks half a
wide as the rim tape width. Beyond that, pinch flats always have an
impression of the bias ply casing embossed into the rubber leaving
characteristic cloth markings.

Above and beyond that, the rider lied about the circumstances,
something that was brought out by the service log of the rescue crew
that picked him up... at home instead of painfully lying on the road
at the scene as he claimed. Meanwhile he cooked up the story so he
could explain his crash to his peers as being someone else's fault.

In court, grazing incident photos clearly showed the cloth marks,
cited the circumstances under which they were made along with the
reconnaissance of the crash scene where there was a pot hole in the
apex of the turn that had to be avoided by cutting inside of it. This
rolled the tire.

All this didn't seem to bother Forester who, if he is as astute as he
puts forth, should have recognized the whole scenario as I did. His
claims did not hold up under scrutiny. The bicycle shop was spared
disaster.

Jobst Brandt
jobst.brandt@stanfordalumni.org
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