odd rim profiles

"Art M" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

What's the rationale/aerodynamics behind some of the odd rim profiles available? Specifically, the
cutaway between the spoke holes on the Ksyriums and the inverted cross-sectional curve of Alex
R390 rims (pic at

nashbar.comprofile moreimages.cfmOpen ↗

Quoted message said:

sku=1128&brand= ).

--Art

Dunno about the Alex rims, but the Ksyriums cutouts are for reducing weight.

Mike

"Mike S." <mikeshaw2@coxDOTnet> wrote in message news:<O0zWb.61043$F15.52507@fed1read06>...

Quoted message said:

"Art M" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

What's the rationale/aerodynamics behind some of the odd rim profiles available? Specifically,
the cutaway between the spoke holes on the Ksyriums and the inverted cross-sectional curve of
Alex R390 rims (pic at

nashbar.comprofile moreimages.cfmOpen ↗

Quoted message said:

sku=1128&brand= ).

--Art

Dunno about the Alex rims, but the Ksyriums cutouts are for reducing weight.

Mike

If you want to look at rim cross-sections, look through the QBP catalog, in particular:
harriscyclery.netpage.cfmOpen ↗

The R390 is an odd cross-section, but I'm not sure I believe the miraculous properties listed on the
Alex site: "Lighter yet stronger than conventional road bike rims with its inside arch design, it
also helps to reduce wind resistance. The thicker inner wall prevents rim deformation caused by hard
braking and improves durability, the deep round inner wall prevents the rim strip from moving from
side to side, and the inner convex design fits the rim sleeve tightly."

(from alexrims.comindex.htmOpen ↗ - click on "Road Pro" then "R390" )

Jeff

Art-<< What's the rationale/aerodynamics behind some of the odd rim profiles available?
Specifically, the cutaway between the spoke holes on the Ksyriums and the inverted cross-sectional
curve of Alex R390 rims (pic at
nashbar.comprofile moreimages.cfmOpen ↗ sku=1128&brand= ).

Quoted message said:

Quoted message said:

<BR><BR>

Like a gent at Interbike said about a really wierd front der I was looking at-

" what's that thing for?", I ask.

"For selling", he says.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

"Qui si parla Campagnolo" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Art-<< What's the rationale/aerodynamics behind some of the odd rim

profiles

Quoted message said:

available? Specifically, the cutaway between the spoke holes on the Ksyriums and the inverted cross-
sectional curve of Alex R390 rims (pic at

nashbar.comprofile moreimages.cfmOpen ↗

Quoted message said:

sku=1128&brand= ).

Quoted message said:

Quoted message said:

<BR><BR>

Like a gent at Interbike said about a really wierd front der I was looking

at-

Quoted message said:

" what's that thing for?", I ask.

"For selling", he says.

LOL. You have a nice economy of dialog. The thing that threw me about the Alex rim was that you
usually don't see that much flair in a bike product that's so inexepensive.

--Art

Quoted message said:

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

Thanks for the links.

There seem to be a many medium aero rims that meet at an angle with the breaking surface. I would
hope that someone has tested and found that any small hit on drag there is less than the improvement
at the tire to rim junction. Or is it just another marketer's whim.

--Art

"Jeff Wills" <[email hidden]> wrote in message
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Quoted message said:

"Mike S." <mikeshaw2@coxDOTnet> wrote in message

news:<O0zWb.61043$F15.52507@fed1read06>...

Quoted message said:

Quoted message said:

"Art M" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

What's the rationale/aerodynamics behind some of the odd rim profiles available? Specifically,
the cutaway between the spoke holes on the Ksyriums and

the

Quoted message said:

Quoted message said:

Quoted message said:

inverted cross-sectional curve of Alex R390 rims (pic at

nashbar.comprofile moreimages.cfmOpen ↗

Quoted message said:

Quoted message said:

Quoted message said:

sku=1128&brand= ).

--Art

Dunno about the Alex rims, but the Ksyriums cutouts are for reducing

weight.

Quoted message said:

Quoted message said:

Mike

If you want to look at rim cross-sections, look through the QBP catalog, in particular:
harriscyclery.netpage.cfmOpen ↗

The R390 is an odd cross-section, but I'm not sure I believe the miraculous properties listed on
the Alex site: "Lighter yet stronger than conventional road bike rims with its inside arch design,
it also helps to reduce wind resistance. The thicker inner wall prevents rim deformation caused by
hard braking and improves durability, the deep round inner wall prevents the rim strip from moving
from side to side, and the inner convex design fits the rim sleeve tightly."

(from alexrims.comindex.htmOpen ↗ - click on "Road Pro" then "R390" )

Jeff