700/23 vs 700/25 tires ?

On Thu, 12 Feb 2009 11:24:15 -0800 (PST), Frank Krygowski
wrote:

Most cyclists aren't trying to
save ten second on their ride; they're
trying to enjoy themselves, or
just get where they want to go.

Wow, Frank, you beat me. You won. I've got no response to that
argument.

Chung's a lot smarter than me but frankly I don't think even he has a
comeback to that.

You win.

On Thu, 12 Feb 2009 11:25:26 -0800 (PST), Frank Krygowski
wrote:

On Feb 12, 1:44=A0pm, John Forrest Tomlinson
wrote:
On Thu, 12 Feb 2009 09:26:54 -0800 (PST), Frank Krygowski

wrote:
Why are these guys not on the drops? =A0http://tinyurl.com/b9m253

The speed is low enough that the improvement in breathing/etc is worth
the aero trade off.

I think we're making progress! You're at least thinking in
comparative terms, rather than absolute terms. Good!

Nice. You get me to say something obvious, then pretend it's in
contrast to my earlier statements to make it look like I'm backing
down.

You're pathetic.

On Thu, 12 Feb 2009 11:42:21 -0800 (PST), Frank Krygowski
wrote:

Oh, he's long gone.

But his casually posted question, "Will 2mm make you that [much]
slower or faster?" indicated to me that he was concerned about a
significant difference, not some difference measurable only with
precision equipment.

Do you disagree?

I don't know. I do know that when some of us said that difference in
bikes, such as tire size, can have a tiny effect, you have comeback
saying that tiny effects are basically non-effects that are lost in
"noise" and should be ignored.

On Thu, 12 Feb 2009 11:44:38 -0800 (PST), Frank Krygowski
wrote:

On Feb 12, 1:54=A0pm, John Forrest Tomlinson
wrote:
On Thu, 12 Feb 2009 18:44:37 GMT, John Forrest Tomlinson

wrote:
On Thu, 12 Feb 2009 09:26:54 -0800 (PST), Frank Krygowski
wrote:

Why are these guys not on the drops? =A0http://tinyurl.com/b9m253

The speed is low enough that the improvement in breathing/etc is worth
the aero trade off.

PS - it's kind of funny to note some of those guy on aero wheels.

It's also funny to note that all those guys have non-aerodynamic water
bottles. Even the guy on the Cervelo! What are they thinking?

It's kind of funny that you think that because someone says that X is
more aero than Y that means they think racers should always use X.

On Thu, 12 Feb 2009 09:26:54 -0800 (PST), Frank Krygowski
wrote:

On Feb 11, 11:28*pm, John Forrest Tomlinson
wrote:
On Wed, 11 Feb 2009 20:10:59 -0800 (PST), Frank Krygowski

wrote:

Nonetheless, if you remain convinced that the shelter of the pack is a
small effect, you certainly shouldn't be coaching.

Nice - now you're just straight-up lying.

I never said anything even remotely close to that the shelter of the
pack being a small effect.

I said that aerodynamics is is important in racing almost all the
time, including in mass start racing (even when on a wheel or in a
pack).

Then you suggest that is not true for riders ""almost completely
shielded from the wind" by a pack.

Which is laughable.

Then you started backtracking about the "almost completely part"

The lies annoy me but please keep dancing around and shifting meaning
-- it's kind of funny.

Why are these guys not on the drops? http://tinyurl.com/b9m253

- Frank Krygowski

Dear Frank,

As others point out, they're climbing--the camera angle is always hard
to be sure about, but at full size the photo lets you see chains on
the big rear sprocket.

Aerodynamics _do_ matter at the speeds pros climb, but most riders
straighten up into a more natural position when they start to climb.
When it gets tough, they climb out of the saddle.

The photo shows a couple of riders wearing wris****ches (horrors, the
extra weight!), some disagreement about whether to carry one or two
water bottles up the hill, and even disagreement about where to place
a single water bottle:
http://i41.tinypic.com/2n19flh.jpg

Yellow circles show three wris****ches (I skipped some bracelets).

Green circles show the two-gun school of water bottles.

Purple circles show disagreement about where to place a single water
bottle.

There's also obvious disagreement about aero or less aero wheels.

The stage winner averaged 36.65 km/h, almost 23 mph, so aero certainly
mattered:
http://www.cyclingnews.com/road/2005...sults/tour0510

Some guys felt like carrying more weight up the hills, others felt
like carrying a different number of water bottles or single water
bottles in different places.

I suspect that they'd laugh if anyone told them that they needed to
get rid of the wris****ches or carry a single water bottle in the more
aerodynamic position.

They'd probably have more serious responses about why they used heavy
aero wheels or light ordinary wheels, though the logic might be hard
to follow.

Cheers,

Carl Fogel

On Feb 12, 11:44*am, John Forrest Tomlinson
wrote:
On Thu, 12 Feb 2009 09:26:54 -0800 (PST), Frank Krygowski

wrote:
Why are these guys not on the drops? *http://tinyurl.com/b9m253

The speed is low enough that the improvement in breathing/etc is worth
the aero trade off.

They're soft pedaling. Look at where the yellow jersey
is - one teammate in front of him, nowhere near the
front. It is obviously not a critical moment in the race.

Ben

On Thu, 12 Feb 2009 13:36:33 -0700, wrote:

They'd probably have more serious responses about why they used heavy
aero wheels or light ordinary wheels, though the logic might be hard
to follow.

Does that make you feel superior?

Did you ever race bikes by the way? It must be nice nowing you're
smarter than those guys.

In article
,
Frank Krygowski wrote:

On Feb 11, 4:12*pm, Michael Press wrote:
In article
,
*Frank Krygowski wrote:



On Feb 11, 4:32*am, Michael Press wrote:
In article
,
*Frank Krygowski wrote:
... if a person finds himself in that position
very often, his problem isn't aerodynamics; it's strategy.

If a tiny aero advantage ever does make the difference in winning a
road race, it can't happen more than once in a blue, blue moon.

You claim that most of the time most of the riders are sucking wheel.
However each spends time in the wind, and typically the same
amount of time. Anybody that tries to suck wheel all the time
is dealt with by the pack. When your time in the wind comes up
do you want your ears flapping like a pennant in a gale?

:-) Of course, like any serious rider, my ears wouldn't be flapping.
As you and others have noted, all serious riders tape their ears back
flat against their heads, for the obvious aero advantage!

The point I'm making about the peloton, which you, Robert and John are
steadfastly refusing to acknowledge, is that for the bulk of a road
race (not time trial), the wind-tunnel predicted magnitude of benefit
is simply not there. The 30 mph relative wind is not there, so the
small predicted benefit is much smaller. And if you really do work in
mathematics, Michael, surely you understand that there are factors
small enough that they don't matter - they're negligible.

The relevant figure is watts dissipated to an aerodynamic
disadvantage compared to the watts available. Does the rider
go into the red zone or not? How many forays into the red zone
does he get in one race? Here is where analysis is difficult.

Now improvement A is negligible,
and improvement B is negligible,
and improvement C is negligible,
and improvement D is negligible,
and improvement E is negligible,
and improvement F is negligible.
Is improvement A+B+C+D+E+F negligible?

(If you prefer, I could say there are factors small enough that the
probability of them mattering in any particular instance is
negligible. I wouldn't want you, like Robert, to ignore the overall
meaning and pounce on any phrase that allows the tiniest opportunity
to yell "gotcha.")

Or do
you want every aerodynamic advantage you can musters against
the competition?

NOBODY with sanity wants every aerodynamic advantage they can muster
over the competition - at least, not in road race or recreational
ride!

Road racing and recreational rides are two different environments.
You mix them for no reason apparent to me.

[...]

I take that to mean "A racer that doesn't tape back his ears, shave
all body hair and file down his fingernails has already lost the
race."

That's what you meant, right? *You must use _every_ "potential
advantage"?

I meant what I said. Dismissing potential advantages is
a recipe for defeat; it means adopting a mental attitude
that does not promote winning.

When I did a little racing I never did tape my ears. How about you?
Seriously!

You choose not to seriously address the argument I make.

--
Michael Press

On Thu, 12 Feb 2009 07:17:06 -0800 (PST), Nick L Plate
wrote:

On 11 Feb, 21:26, wrote:
"Tying" probably means merely bending the spokes where they cross, not
actual tying with wire and soldering. As mentioned later, this is
supposed to remove the "arc" and make the wheel stiffer and longer
lasting.

You are again wrong.
When I use the term tying, I mean tying with thin iron/steel wire.


"At this point the nipples are nipped down . . . " may mean that the
spoke nipples are crimped with pliers to prevent them from unscrewing?

And again. Perhaps I didn't use the best term here, snugged may have
been better. Obvious when continuing to read the rest of my post that
crimping the nipples would not enable the spokes to be brought to
working tension. Just use fingertips, no torque to tension spoke.

Dear Trevor,

Good lord!

So you actually tie your spokes together with wire?

Just to pin down the details, is the tying enough, or do you also
solder the wire?

Alas, nothing is obvious in your posts:

"Just use fingertips, no torque to tension spokes."

Classic!

Maybe that means that you estimate "working tension" by pushing the
spokes sideways with your fingertips instead of using a tension gauge?

"Torque" might be the wrong word for tensiometer, but it might be
something else, if you've developed a method of tightening spoke
nipples without torque.

Cheers,

Carl Fogel

Frank Krygowski wrote:
On Feb 12, 1:03 am, "Robert Chung"
wrote:
Frank Krygowski wrote:

As Carl said, you claimed that new water bottles (NOT entire new
super- aero bikes) reduce CdA much more. Can you give us data just
on water bottles, not on entire new frames?
Of course. But first, I don't believe the Rocket Science Sports claims that
Carl pointed to so I ignore them. Here's someone I do believe: Damon Rinard
(remember Damon? Damon used to post here but doesn't any more. Ever wonder
why?) tested Bontrager Speedbottles. At zero yaw a Speedbottle on the
downtube is about 0.3 sec/km faster than a conventional round bottle on the
downtube, or about 15 secs per 40km.

Are you talking about time trials yet AGAIN? Instead of road races or
recreational rides?

Would you like to give a reasonable estimate for what I am actually
discussing... the time benefit for an actual road race, instead of in
a wind tunnel or time trial? And when you've done that, could you
discuss the tremendous advantages for non-competitive cyclists, like
the OP?

That's 3x better than the 2003 Profile
bottle when compared to a conventional water bottle. You know, the Profile
bottle that only idiots think that mass-start racers can use.

:-) Or the Profile bottle that I already pointed out was usable only
with illegal (for road racing) bars, a fact a certain reader somehow
missed!

Since I've admitted my prior mistake on a rather irrelevant time
calculation, you have an opportunity to do likewise on this point.
Got class?

Anyway, the
interesting thing is that this benefit reaches its *minimum* at zero yaw. As
yaw angle increases, the Speedbottle's advantage gets larger and larger. The
problem with the Bonty was supposedly the cage, not the bottle itself.
Arundel water bottles are supposed to be in the same ballpark (and with the
same non-zero yaw behavior) as the Speedbottle, but they've been working on
a cage that holds the bottle securely. The bottles are kinda expensive so if
you hit a bumnp and lose one it can add up.

What I'm waiting for is the conclusion. I keep asking why road racers
don't universally use these amazing technical advantages you keep
referring to. Are the "idiots" all the road racers that still use
cylindrical bottles? Should you not be scolding and haranguing them?

Because every time a road racer pops a standard bottle in his cage,
he's agreeing with me and disagreeing with you. Or he's making a
quick judgment based merely on fashion.

What are you doing to correct this travesty? Hmm... maybe you're not
insulting them enough?

"I keep asking why road racers don't universally use these amazing
technical advantages you keep referring to"

Because that's how it is. It's an essential aspect of the sport.

In Keirin, all the equipment is effectively identical save frame color
(Td'F was once like that, see also "Little 500" race)

The combination of genetic ability, skill set/experience, metabolic
aptitude (VO2 and muscle) from training as well as equipment choices all
have wide variance.

As I mentioned earlier, if an equipment change is _no worse_ but the
rider feels it adds an edge, (s)he'll perform well. No harm at all in that.

There's a counter trend too; it isn't a ratchet effect. Ask any Masters
racer if he would go back to thirty year old 'superlight' trendy gear
with a real risk of DNF or injury.

As much discussed, parameters of equipment choice may include function,
aero, weight, durability, cost and probably fashion. The combination is
so complex that there may be no single 'right' or 'best' answer for
every portion of every event.

Riders may make various choices and that's good. As with any process
that has feedback loops, riders will either adopt or abandon various
equipment choices based on performance over the long term.

Else we'd be in 'heaven', another word for 'stasis'. feh.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971