For Mr Chisholm

Ron Ruff wrote:
Sorni wrote:

Delta?

Speed compared to the best tire.

Merci.

http://www.rouesartisanales.com/article-1503651.html

It should take you right to the article.

Similar to the results of IRC tests done years ago, tubulars had
higher RR than clinchers. Tests performed over a range of inflation
pressures as the IRC tests were, reveal more about where the RR occurs
than just final values. Two inflation pressures do not give the
overview of continuous curves over a range that encompasses all
operating levels.

Sorry to come into this thread so late, but regarding the clincher rolling
resistance charts, isn't is the case that, the narrower a tire, the higher
the PSI required for optimal rolling resistance? The clincher chart shows
only one inflation pressure used, a rather-low (particularly for a 22mm
tire) 101 PSI. And, interestingly, the best results at that pressure came
from a tire that had the greatest width, while the poorer results were
generally from narrower tires.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com


wrote in message
...
Jeff Starr writes:

Still nothing. All I get are the topics and the pic at the top
with the two wheels and the tied and soldered spoke pic(too loose
BTW), but nothing else. Not even on the english language links.

Peter, try this link:

http://www.rouesartisanales.com/article-1503651.html

It should take you right to the article.

Similar to the results of IRC tests done years ago, tubulars had
higher RR than clinchers. Tests performed over a range of inflation
pressures as the IRC tests were, reveal more about where the RR occurs
than just final values. Two inflation pressures do not give the
overview of continuous curves over a range that encompasses all
operating levels.

http://www.sheldonbrown.com/brandt/r...e-tubular.html

Rolling losses in tires with smooth tread are caused by casing, tread,
and inner tube flex, while tires with tread patterns additionally have
tread squirm. Tread squirm, the lateral bulging of tread rubber into
voids, is most apparent on knobby tires whose knobs bulge in width and
breadth while grooved tire tread squirms laterally only.

Tubular tires have the same losses as clinchers, except that movement
between tire and rim in viscous rim glue adds a fixed loss
(independent of inflation pressure) that ultimately makes them poorer
performers, unless hardening track glue (shellac) is used. This and
tread squirm characteristics are not discernible in data presented at
rouesartisanales.

I would like to see the same kind of data display from Continental
that IRC did because it reveals more about tires besides not relying
on a single measurement.

Jobst Brandt