700/23 vs 700/25 tires ?

On Sun, 01 Feb 2009 01:11:09 GMT, John Forrest Tomlinson
wrote:

On Sat, 31 Jan 2009 17:44:58 -0700, wrote:

As always, it's your imagination and over-sensitive reaction, not my
lack of understanding.

But keep on ranting that victory depends on details likely to be lost
in the noise or even mistaken--the law of averages suggests that
you'll have to be right occasionally, and the challenge for the rest
of us is to make sure that we don't just dismiss you automatically.

I said it can be affected by details. You've repeatly said that
because something has a tiny or extremley difficult to measure effect
it has no effect.

And you're repeatedly refused to answer simple questions I've asked
you whereas I've answered many of yours.

Cluck cluck cluck


Excuse me, I have to clarify something about the first paragraph I
wrote above. Carl, you have generally been too cowardly to assert that
a tiny difference is not a difference, but rather you have implied it
over and over again by asking me to quanitify things. That is, you
not only are too cowardly to answer questions I put to you, you are
often (though not always) too cowarwdly even to assert things in a
positive manner but instead suggest those things over and over again.
Your meaning is clear enough, but I guess that allows you some sort of
mental defense against saying things that are clearly wrong.

Sorry to not say that in the first place.

Chalo wrote:

My point is that the fastest
bike riders around used to agree that
40mm tires were the best, then later
they agreed that 19mm tires were
best, and now it's something else. Were they all correct?

Hhhmm, well if we compared the speed of the riders on 40s and riders
nowadays, who is going faster?

But , I'm not familiar with those days that 40s were common -- it's
possible that that was the best given the materials tires were made of
at the time.

More generally, knowledge increases over time, so absent other
changes, what is chose later is probably better that what was chosen
earlier. Sometimes we overshoot -- the move to super narrow tires by
men of average weight was an example, but the fact that 20s and 19s
were briefly used and then average racing men now choose 23s adds more
weight to likelihood that 23 is best for racing men of average height
and good weight (that is, not heavy).

On Fri, 30 Jan 2009 11:31:22 -0700, wrote:

Carl, do you have any practical experience in bike racing whatsoever?
And if so, did you achieve success of any kind?

Dear John,

Ah, your usual signal that you have no argument!

Ah Carl, the usual inability to answer a simple question about
yourself.

Did you acutally try racing and just suck? Did some riders you
thought were racers make fun of you and hurt your feelings? Or did you
give some advice to some beginning bike racer and they followed your
advice and then realized you don't know what you're talking about?

I guess if it's something really embarrassing like that (though the
second scenario is really no fault of your own and the first really
isn't bad either, you might not be cut out for it. I'm bad with
speaking foreign languages -- no big deal) you don't want to talk
about it, but a simple "Yes" or "no" might help.

wrote:

You're the one who proposed mysterious "wrong" wheels causing flats in
Paris-Roubaix, not me. It's up to you to tell us what's wrong with
them--I have no idea what you're thinking.

I put a question mark at the end. "Something wrong with the wheels?". I'm
not claiming it's the cause, I'm asking if it could be. I remember hearing
complaints about wheels one year I watched the race on TV. I don't remember
the details.

The same thing is true of the mysterious "slow leaks" that you propse
to explain the well-known impact flats that plague Paris-Roubaix every
year in the cobblestone sections.

Slow leaks are common in road races, and are bound to be even more common on
poor surfaces. They're more likely to lead to a pinch flat when the surface
is cobbled. Not all that bizarre a theory, is it?

But since you're asking for help, I'll give you what I can. I was
surprised, too, when I learned that some impacts can damage a rim
without causing an impact puncture (and vice-versa).

I know that already from experience. By the way, the bent rims I mentioned
were bent sideways in the crash rather than getting dinged from any direct
initial impact.

What happens depends roughly on how broad the impact area is--you can
spread enough force out over a rim to damage it splitting the inner
tube. Speed, inflation, rim brand, rider weight, and so on make it
well-nigh impossible to predict what will happen with any given
pothole, crack, or chunk of gravel.

OK, if I accept that the cobblestones on the Paris-Roubaix cause
pinch-flats, the riders hit thousands of them before suffering the bad luck
of a pinch flat, and some ride over millions of them without getting any
flats. What relevance does that have to me, mainly riding on reletaively
good surfaces, only occasionaly hitting very nasty objects at 20 to 30 mph,
none of which have caused a pinch flat except when the tyre pressure has
been low?

As for what I know about Paris-Roubaix, it's not unheard of for RBT
posters to post bizarre theories that hitting the cobblestones is
somehow not the cause of the swarms of flats, ruined wheels, and
crashes, decade after decade.

Do you know what proportion of the flats suffered on the P-R are pinch
flats? Do you know what proportion of the pich-flatted tyres had an
ordinary puncture shortly before? Has anyone examined the tubes?

~PB

On Sat, 31 Jan 2009 17:44:58 -0700, carlfogel wrote:
Dear John,

As always, it's your imagination and over-sensitive reaction, not my
lack of understanding.

But keep on ranting that victory depends on details likely to be lost in
the noise or even mistaken--the law of averages suggests that you'll
have to be right occasionally, and the challenge for the rest of us is
to make sure that we don't just dismiss you automatically.

Cheers,

Carl Fogel

I lean quite a bit from a few of the posters here. I've found many of
Carls posts interesting, and some informative. That said, I've done some
racing of different styles, some bike and some non. A couple things I
learned over time are never to dismiss the input of an experienced and
successful racer, and practice often trumps theory. You can research for
weeks, but a lesson from someone who's already good usually means more.

I'm not going to start dismissing JFT, an accomplished racer, anytime
soon. Not when it comes to bikes and racing.

On Sat, 31 Jan 2009 14:37:53 -0600, Carl Sundquist
wrote:

[snip]

I don't think the UCI banned Steve Bauer's 1993 bike. They don't get
much more ridiculous than that. Unfortunately I can't find a link on the
web.

Dear Carl,

See page 3 for photo and desciption of Bauer's bike, which involved
sitting far back over the rear wheel:
http://www.fizik.it/files/pressBook/CYCLE_SPORT_USA.pdf

Some raw comments on Bauer's 1993 stretch ride:
http://www.serotta.com/forum/archive...hp?t-6580.html

Cheers,

Carl Fogel

Ryan Cousineau wrote:
I agree with Carl's claim that "all too often, we have no real
evidence whether [racers] won because or in spite of their
equipment."

and

Carl, in my opinion, has thought about this question as carefully as
most bike racers. He has thought about it at least as carefully as I
have.

Were this rbr, I'd have a salutation to offer you.

More to the point, Carl is right: there's a lot of equipment choices
in bike racing that are either hard to analyze, or hard to defend.

Perhaps. However, we actually know quite a bit about certain types of
equipment, including tires.

In article
,
Chalo wrote:

dusoyevsky wrote:

Chalo wote:

As I've pointed
out, early 20th century racers used tires about 1.5" wide on their
bikes, thinking that was faster than the alternatives.

Of course roads (speaking of the 20's) were not the
equal of the good roads of more recent times.

But the velodromes and tracks where most racing took place were
smoother than today's roads and most of today's 'dromes.

IMHO it goes to flats-- you use the smallest (lightest, most aero)
tire you can that doesn't "flat too often".
Note the handling problems seen on the TT bikes, where they're using
small-section tires pumped hard. That tells you something about
"priorities", which may have a basis in wind tunnel testing-- and
probably does with LanceCo.

There has been a whole lot less effort expended in fairing the tire to
the rim than I would expect. A tire-rim system with the shape and
width of both parts controlled to give an aerodynamically efficient
shape would yield much better results than just making the tire
smaller. Deep section rims are a move in that direction, but rims
that combine with the tire to make a streamlined unit would be much
better-- and they wouldn't have to be silly narrow either.

It's happening. Zipp already has a matched (dimpled?) tire for their
wheels. And read this note:

http://www.trisports.com/hedst90fr.html

"The 2006 Stinger 90 is designed to be most aero with a 22mm tire. A
19mm tire will not be as fast, and will not adhere to the rim as well as
a 21-23mm tire."

I think the wheels are where the fairing-in is being done, since it's
easier to mess with rim shapes than sidewall shapes.

--
Ryan Cousineau http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."

Nick L Plate wrote:

Chalo wrote:

My point is that the fastest bike riders around used to agree
that 40mm tires were the best, then later they agreed that
19mm tires were best, and now it's something else. *Were they
all correct? *If they weren't all correct, why should we
believe that it's racers who use 23mm tires who have it right?

Yes, they were, at that time, considering their equipment, their
event and themselves.

So, in your estimation, is there enough difference between mass start
pro road racing in the '80s and mass start pro road racing in the '00s
to merit a 21% difference in nominal tire width?

What happened in the intervening years to make the fastest possible
tire fatter than it had been before?

Chalo

On Sun, 1 Feb 2009 01:42:33 -0000, "Pete Biggs"
t wrote:

wrote:

You're the one who proposed mysterious "wrong" wheels causing flats in
Paris-Roubaix, not me. It's up to you to tell us what's wrong with
them--I have no idea what you're thinking.

I put a question mark at the end. "Something wrong with the wheels?". I'm
not claiming it's the cause, I'm asking if it could be. I remember hearing
complaints about wheels one year I watched the race on TV. I don't remember
the details.

The same thing is true of the mysterious "slow leaks" that you propse
to explain the well-known impact flats that plague Paris-Roubaix every
year in the cobblestone sections.

Slow leaks are common in road races, and are bound to be even more common on
poor surfaces. They're more likely to lead to a pinch flat when the surface
is cobbled. Not all that bizarre a theory, is it?

But since you're asking for help, I'll give you what I can. I was
surprised, too, when I learned that some impacts can damage a rim
without causing an impact puncture (and vice-versa).

I know that already from experience. By the way, the bent rims I mentioned
were bent sideways in the crash rather than getting dinged from any direct
initial impact.

What happens depends roughly on how broad the impact area is--you can
spread enough force out over a rim to damage it splitting the inner
tube. Speed, inflation, rim brand, rider weight, and so on make it
well-nigh impossible to predict what will happen with any given
pothole, crack, or chunk of gravel.

OK, if I accept that the cobblestones on the Paris-Roubaix cause
pinch-flats, the riders hit thousands of them before suffering the bad luck
of a pinch flat, and some ride over millions of them without getting any
flats. What relevance does that have to me, mainly riding on reletaively
good surfaces, only occasionaly hitting very nasty objects at 20 to 30 mph,
none of which have caused a pinch flat except when the tyre pressure has
been low?

As for what I know about Paris-Roubaix, it's not unheard of for RBT
posters to post bizarre theories that hitting the cobblestones is
somehow not the cause of the swarms of flats, ruined wheels, and
crashes, decade after decade.

Do you know what proportion of the flats suffered on the P-R are pinch
flats? Do you know what proportion of the pinch-flatted tyres had an
ordinary puncture shortly before? Has anyone examined the tubes?

~PB

Dear Pete,

Why would slow leaks be more common on cobblestones? The debris is
usually down in the cracks.

The riders in Paris-Roubaix hit more nasty bumps in one day at higher
speeds than most of us hit in years of riding.

Now you've stated that your experience and Paris-Roubaix are not
relevant to each other, but you still seem to think that your
experience is

Why do you think that there is anything except impact flats causing
the typical rider in Paris-Roubaix to expect flats? Is the course
deliberately salted with goathead thorns to cause slow leaks?

Where else do riders in a road race expect dozens and dozens of flats,
ruined wheels, and crashes _every_ year?

Do you think that the cause has remained mysterious for over a
century? That no one has examined the tubes, noted the obvious impact
punctures, and admitted that there's no real remedy for a traditional
bicycle going at racing speeds over miles of cobblestones?

Forgive me, but it's hard to take conspiracy theories about flat tires
at Paris-Roubaix seriously. If you find some evidence that the vast
majority of the numerous flat tires in that race are anything but the
obvious and expected result of going that fast over nasty
cobblestones, let us know.

Cheers,

Carl Fogel