On Nov 27, 8:22 am, "
[email protected]" <
[email protected]> wrote:
> On Nov 26, 11:45 am, [email protected] wrote:
>
> > You'd better decide whether you're talking about racing or not.
>
> YOU'RE the one who brought racing into the discussion.
Nope. Not so. Both Carl Fogel and SocSecTrainWreck mentioned it
earlier than I did. Check the posts. I was merely following the
course of the conversation.
>
> (In reaction to the typical snotty Frank Krygowski-style "you'd
> better blah blah blah).
<sigh> D-y, you've got a knack for misinterpreting my tone, plus an
incredible chip on your shoulder! I had nothing "snotty" in mind when
I replied to you, and nothing in my tone was intended to sound that
way.
If you can't stand even mild disagreement, you shouldn't be posting to
Usenet.
No, wait! Strike that! Replace it with:
In my humble and respectful opinion, if mild disagreement disturbs and/
or distresses you, you might want to consider finding another way to
pass your time. Your interpretation of Usenet posts may possibly
induce unpleasant negative emotions, and I certainly wouldn't want any
unpleasantness at all to befall such a nice guy! ;-)
> > If you're
> > not, neither a small reduction in wheel inertia nor a small
> > reduction in wheel aero drag matter, so the tradeoff between the two
> > is moot.
>
> Moot? You seem to want to think so. Other people might not, for
> obvious reasons.
Of course others may think differently. And, for a given set of
criteria, one side might be right and the other side wrong. So why
not deal with the facts, instead of taking offense at any
disagreement?
>
> > If you are talking about racing, you'd _better_ be riding over "15mph
> > or so." And then, that tradeoff goes in favor of aero, not less
> > inertia.
>
> Unless we're going up a long, steep climb. That's why people who can
> spend a comparatively large sum on the lightest wheel they can get
> with the most aero in it.
Sorry, but "the lightest wheel with the most aero" is not what I was
talking about - because it doesn't exist. I was discussing the
tradeoff between two conflicting benefits.
>
> > We also need to review the concept of "negligible." Do you shave off
> > your arm hair before a road race? I never did, even though I know it
> > would have "helped" at some level. Some effects really do disappear
> > in the noise.
>
> Typical Krygowsky rhetoric. Attempt to ridicule, set up a straw man.
Nope, attempt to illustrate. Failed attempt, I see.
The point is, small theoretical performance benefits are not reliable,
and are often negligible. That includes minor aerodynamic
advantages. (Remember Shimano Aero groups, or whatever they were
called? Where are they now? Why didn't they stick around?)
And in most riding done with an objective of even moderate speed or
distance, inertia changes are less valuable than aerodynamic changes
of equal magnitude.
>
> You still didn't make that seven seconds for 40k go away, Frank.
If you want to theoretically "prove" the seven second benefit in the
context of what I've been saying, here's what you do: You spec two
wheelsets, one with a bit less inertia and a bit more aero drag
compared to the other wheelset. Ideally, make the differences of
equal percentage magnitude (i.e. 5% less inertia, 5% more drag). And
since we're talking inertia (vs weight), adjust the weight of the bike
+rider to keep it constant.
Put those two bikes into one of the bike performance calculators.
Report back on which is faster over the 40k time trial.
I think you'll find the seven seconds goes away very nicely. The aero
advantage on the bike with more slippery wheels will more than consume
the inertia disadvantage.
If that were not so, these guys
http://en.wikipedia.org/wiki/Individual_time_trial
would be stripping off those high-inertia rear disks.
- Frank Krygowski
