32 spoke wheels in Tour de France? - Page 2

On Sat, 12 Apr 2003 15:25:13 +0000, Frank Riley wrote:

> "David L. Johnson" <david.johnson@lehigh.edu> wrote in news:b77v7n$6bq@fidoii.CC.Lehigh.EDU:
>
>> On Sat, 12 Apr 2003 02:00:30 +0000, Jiyang Chen wrote:
>>
>> 3) Rotational weight is weight, pure and simple.
>
> Not quite. Heavier wheels have more angular momentum, which is proportional to rotational inertia,
> which, in essence, means a spinning wheel wants to keep on spinning. This is an advantage on long
> flats, but a disadvantage in sprints and climbs.

How, pray tell, would that be an advantage on long flats? The only extra energy input is in
accellerating that huge mass to obtain the required rotational inertia. To get an idea of the amount
of energy that takes, put your bike on a stand, put it in your biggest gear, grab the pedal with one
hand, and spin the rear wheel. That sucker is probably going as fast as it would at 30mph or more.
Now, of course you double that seeing as how you have two wheels, but that was one push on a pedal
with one hand.

Once you get to cruising speed, you are not accelerating the wheel much at all, so the issue is
moot. But even with a lot of acceleration, that rotational energy is small potatoes. By the way, in
climbing, as long as your speed is reasonably uniform, the only problem is getting the mass up the
hill. Again, no change in speed means no need to contribute to the rotational energy. You do, of
course, have to carry that weight up the hill, be it on the rim or on your waist.

--

David L. Johnson

__o | You will say Christ saith this and the apostles say this; but _`\(,_ | what canst thou say?
-- George Fox. (_)/ (_) |

On Sat, 12 Apr 2003 20:38:13 +0000, Antti Salonen wrote:

> Jiyang Chen <Jiyangc@yahoo.com> wrote:
>
>> A cycling catalog... "Upgrading from a 32 spoke wheels to Mavic Ksyrium Elites save half a pound
>> of rotational weight, or 2-3 pounds elsewhere."
>
> This is almost definitely marketing BS. Ksyrium Elites are HEAVIER, not lighter than a pair of
> hand-built 32-spoke wheels of the same price.

I don't know about that. For the same price you can get gold-plated rims, which would add to the
"rotational weight".

--

David L. Johnson

__o | "It doesn't get any easier, you just go faster." --Greg LeMond _`\(,_ | (_)/ (_) |

> Anyway, the days of riding on 32 spoked wheelsets built by some old guy at the bike shop are
> forever long gone. Old silly stuff like Mavic's CXP-33, Open Pros, and MA3 aren't going to get you
> anywhere and look really cluncky.

In the Tour de France, that's certainly true. I spent some time last night going over the photos I took during
the last 3 TDFs. There were no "conventional" wheels in evidence in any of the photos. Some of that
has to do with sponsorship $$$, some with aerodynamics. Aerodynamics don't mean squat when you're in
the middle of the peloton, but they can become significant if you're off the front. Does the cannon
fodder (domestique) need aero wheels? In most cases, probably not. But it's easier for the team
mechanic if he only has to deal with one type of equipment, and it's better for the wheel sponsor
when their product gets greater exposure.

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

On Mon, 14 Apr 2003 17:21:21 +0000, Mike Jacoubowsky wrote:

>> Anyway, the days of riding on 32 spoked wheelsets built by some old guy at the bike shop are
>> forever long gone. Old silly stuff like Mavic's CXP-33, Open Pros, and MA3 aren't going to get
>> you anywhere and look really cluncky.
>
> In the Tour de France, that's certainly true. I spent some time last night going over the photos I took
> during the last 3 TDFs. There were no "conventional" wheels in evidence in any of the photos. Some
> of that has to do with sponsorship $$$, some with aerodynamics.

BS. It _all_ had to do with sponsorship dollars.

> Aerodynamics don't mean squat when you're in the middle of the peloton, but they can become
> significant if you're off the front.

I remember seeing Jalabert (sp?) reaching down to re-do his brake QR after a climb. His "high-tech"
wheels gave so much on the climb that the brake would rub otherwise. Such an advantage. Also keep in
mind the sight of the US Postal team time trial in '01, blown apart literally by crosswinds that
caught the big flat sides of their aerodynamic wheels. Sure, they would have helped if the wind was
calm, but it wasn't anywhere near calm and they rode them anyway. What's to blame there, bad
management or the insistance of sponsors?

--

David L. Johnson

__o | A mathematician is a machine for turning coffee into theorems. _`\(,_ | -- Paul Erdos
(_)/ (_) |

> BS. It _all_ had to do with sponsorship dollars.

> BS. It _all_ had to do with sponsorship dollars.

> Also keep in mind the sight of the US Postal team time trial in '01, blown apart literally by
> crosswinds that caught the big flat sides of their aerodynamic wheels. Sure, they would have
> helped if the wind was calm, but it wasn't anywhere near calm and they rode them anyway. What's to
> blame there, bad management or the insistance of sponsors?

And people call *me* cynical?

Whether your sponsor is Mavic or Rolf or Bontrager, they really don't give a rat's tail which of
their wheels you use in a given event, as long as you use their wheel. Postal (and every other Tour de France
team) has a number of special and general-purpose wheels at their disposal...most often by the same
manufacturer. The choice of which wheel to use for a given course, *especially* for a time trial, is
never the sponsor's. They sign a contract that says they'll professionally represent the product,
not that they'll use a aero wheel with "big flat sides" in every time trial.

Your bone to pick is with the team manager and perhaps some riders, maybe the mechanic. But it's not
with Mavic or Bontrager or whomever. So, to answer your specific question, "bad management" is to
blame. Sorry it cannot be more insidious than that.

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

"David L. Johnson" <david.johnson@lehigh.edu> wrote in message
news:b7fgjh$eqe@fidoii.CC.Lehigh.EDU...
> On Mon, 14 Apr 2003 17:21:21 +0000, Mike Jacoubowsky wrote:
>
> >> Anyway, the days of riding on 32 spoked wheelsets built by some old guy at the bike shop are
> >> forever long gone. Old silly stuff like
Mavic's
> >> CXP-33, Open Pros, and MA3 aren't going to get you anywhere and look really cluncky.
> >
> > In the Tour de France, that's certainly true. I spent some time last night going
over
> > the photos I took during the last 3 TDFs. There were no "conventional" wheels in evidence in any
> > of the photos. Some of that has to do with sponsorship $$$, some with aerodynamics.
>
> BS. It _all_ had to do with sponsorship dollars.
>
> > Aerodynamics don't mean squat when you're in the middle of the peloton, but they can become
> > significant if you're off the front.
>
> I remember seeing Jalabert (sp?) reaching down to re-do his brake QR after a climb. His
> "high-tech" wheels gave so much on the climb that the brake would rub otherwise. Such an
> advantage. Also keep in mind the sight of the US Postal team time trial in '01, blown apart
> literally by crosswinds that caught the big flat sides of their aerodynamic wheels. Sure, they
> would have helped if the wind was calm, but it wasn't anywhere near calm and they rode them
> anyway. What's to blame there, bad management or the insistance of sponsors?
>
> --
>
> David L. Johnson
>
> __o | A mathematician is a machine for turning coffee into theorems. _`\(,_ | -- Paul Erdos
> (_)/ (_) |