Re: Titanium ride verse CF

On Mon, 12 Oct 2009 09:47:37 -0700 (PDT), Frank Krygowski
<frkrygow@xxxxxxxxx> wrote:

On Oct 12, 7:26 am, Johnny Twelve-Point presented by JFT
<usenetrem...@xxxxxxxxxxx> wrote:
On Sun, 11 Oct 2009 18:50:59 -0700 (PDT), Frank Krygowski

<frkry...@xxxxxxxxx> wrote:

He concluded that tires (esp. wide, low pressure ones) gave much more
improvement than anything else, with 75 psi requiring significantly
less pedal power than 100 psi.  And that racers on Paris-Roubaix
should be on much fatter, lower pressure tires than they are.

I have two questions about this last paragraph:

Did the conclusion about what the races "should" do take into account
that the large majority of the Paris-Roubaix race is ridden on normal
(not cobbled roads).

Yes.

And do you know what pressure the guys winning that race are typically
running in their tires?  I think it's 70-80psi already.

In the article, Heine said some teams were using 100 psi rear, 95 psi
front. I'm not sure if those were with suspension forks or not. But
this web page, cited in the article's footnotes, talks about lower
pressures:

http://img2.tapuz.co.il/forums/1_115529144.doc

- Frank Krygowski

Dear Frank,

Interestingly, that 2008 article talks about punctures and stability
(to avoid crashes) in regard to tire pressure, not rolling resistance.

It's easier to read at the web site than in document form.

"For more information on the traditional wheel approach, we placed a
call to BKW friend and PRO mechanic George Noyes. As a recap, George
turned wrenches for cycling's best and did his time in the trenches
for 7-Eleven, Motorola, Cofidis, and Mapei. George has built enough
wheels in his career to fill a stadium and included in his builds are
wheels that carried the Lion himself to victory at Roubaix. . . ."

"Tire pressure remains as much art as science. According to George,
the ideal tire pressure for the Roubaix course walks a very fine line,
balancing enough pressure to keep the rider above the stones and low
enough that the bike feels stable and provides shock absorption. Like
cyclocross, tire pressure is considered too high if the rider doesn't
frequently bounce off the rim."

"The best riders have mastered the art of riding 'lightly' enough that
they can run a ridiculously low pressure without puncturing. Typical
pressure for the Mapei riders hovered around 5 3/4 bars (83 PSI) for
the rear and a shockingly low 5 bars (72 PSI) in the front. 'The lower
the pressure, the more stable the bike is over the stones,' notes
George."

"During our talks, George laughed as he recalled Museeuw's tendency to
bleed out air prior to the start of Roubaix. This served as an outlet
for nervous energy and the best were always pushing the envelope,
seeking the lowest possible pressure. 'I used to threaten to glue the
valves closed so Johan could not change the pressure,' says George."

http://www.belgiumkneewarmers.com/2008/04/tradition-vs-technology.html

Even with wide tubulars at low pressures, flats and crashes on the
straights are routine in Paris-Roubaix:

"'I crashed once and punctured three times,' Maaskant told VeloNews."
http://www.velonews.com/article/90463/boonen-blitzes-paris-roubaix

That's from the 2009 Paris-Roubaix, won by Boonen in about 6 hours 15
minutes at about 26 mph over about 162 miles.

Cheers,

Carl Fogel
.

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