Comfortable Wheelsets - Again?

Quoted message said:

I have a set of old Matrix Aurora box rims laced to Shimano Ultegra
hubs, 32 spoke round. Old school, or rather, old. W

Quoted message said:

they are
definitely the most comfortable as far as smoothness and roadsoaking
ability.

Quoted message said:

I am wondering
if these old things are the most comfortable, then why is it?

It's because they've aged into smoothness, like a fine wine. Sell them
on Ebay for lots of $$, or continue aging them & save them for your
kids.

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In article <[email hidden]>,

Quoted message said:

I have read quite a few posts regarding the "comfort" and "softness" of
different wheelsets. Each thread usually starts with someone advocating
the stiffness or comfort of a particular wheel, and ends with "you
can't tell the difference because deflection is too small on any
wheelset".

I have a set of old Matrix Aurora box rims laced to Shimano Ultegra
hubs, 32 spoke round. Old school, or rather, old. While I would never
say they are the most responsive wheels I've ridden, they are
definitely the most comfortable as far as smoothness and roadsoaking
ability. I have compared them to Mavics/Ultegras (low rim), custom
Velocity's (med rim) and Bontrager X Lite (deep).

By comparing I mean same bike (steel), same tubes and tires
(Vredsteins) with same tire pressure (100). Not believing myself, I
dragged my wife and a couple of friends into this. Independently, we
all chose the Auroras.

I am not submiting that this is the absolute way it is. I am wondering
if these old things are the most comfortable, then why is it? If
deflection is truly too minute to detect, what other variables apply?
Does a heavier wheel mute road noise better? Spoke style and
application? Can a hub create ride differences? I'd be very interested
to know why, to me, different wheelsets feel very differently. I don't
know.

_ This is just a wild a** guess, but the one variable that pops
to mind is rim width, in effect a wider rim can make a small
tire wider in some sense[1]. If you're really curious you might
try measuring the contact patch on the various wheels,
unfortunately I don't have any good ideas on how to do this.

_ You could also make statements about more spokes dampening out
low frequency vibration modes, but "vibration dampening" is
generally accompanied by lot's of snake oil and there doesn't
seem to be any way discuss it emprically. Wheels ting very
nicely without tires on them so they must have some resonant
frequencies, going from there to vibrations of the saddle
and handlebars is unfortunately where the snake oil seeps
in....

_ Booker C. Bense

[1]- The radius of the inflated tube is limited by tire size +
rim width, so on a wider rim at the same pressure a tire will
have more volume of air. The more I think about this the
less convinced I am that it would make a difference...

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In article <[email hidden]>,

Booker C. Bense said:

In article <[email hidden]>,

Quoted message said:

I have read quite a few posts regarding the "comfort" and "softness" of
different wheelsets. Each thread usually starts with someone advocating
the stiffness or comfort of a particular wheel, and ends with "you
can't tell the difference because deflection is too small on any
wheelset".

[ comparison snipped.

Quoted message said:

Quoted message said:

I am not submiting that this is the absolute way it is. I am wondering
if these old things are the most comfortable, then why is it? If
deflection is truly too minute to detect, what other variables apply?
Does a heavier wheel mute road noise better? Spoke style and
application? Can a hub create ride differences? I'd be very interested
to know why, to me, different wheelsets feel very differently. I don't
know.

_ This is just a wild a** guess, but the one variable that pops
to mind is rim width, in effect a wider rim can make a small
tire wider in some sense[1]. If you're really curious you might
try measuring the contact patch on the various wheels,
unfortunately I don't have any good ideas on how to do this.

Quoted message said:

[1]- The radius of the inflated tube is limited by tire size +
rim width, so on a wider rim at the same pressure a tire will
have more volume of air. The more I think about this the
less convinced I am that it would make a difference...

_ I thought about this some more during my afternoon bike ride
and came to the conclusion that for a relatively small tire the
volume of the rim and tire combo could very well be different
enough to affect the feel of the wheels. For any given
displacement of the tire, the relative change in volume for
a boxy wide rim is going to be less than for a narrower
more aero rim. Thus while the two tires start at the same
pressure, the pressure in response to a bump[1] is going to
be higher for a smaller rim. Boyle's law in action..

http://www.grc.nasa.gov/WWW/K-12/airplane/aboyle.html

_ Booker C. Bense

[1]- A fixed size change in volume.

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Thank you Booker, good thoughts.

skim

Booker C. Bense said:

For any given
displacement of the tire, the relative change in volume for
a boxy wide rim is going to be less than for a narrower
more aero rim. Thus while the two tires start at the same
pressure, the pressure in response to a bump[1] is going to
be higher for a smaller rim. Boyle's law in action..

The increase in tire pressure is miniscule, the difference in tire
pressure change between the wheels would be a miniscule fraction of
that miniscule amount -- smaller than the princess's pea.