Re: [CR]Urban Legends, by Jobst Brandt

(Example: Framebuilders:Alex Singer)

Date: Mon, 18 Aug 2003 22:15:16 -0500
Subject: Re: [CR]Urban Legends, by Jobst Brandt
From: "Todd Kuzma" <tullio@theramp.net>
To: <dbilenkey@sympatico.ca>, <Classicrendezvous@bikelist.org>
In-Reply-To: <HBECIOPCNPKEJLCJBKNKKEEFGLAA.dbilenkey@sympatico.ca>


on 8/18/03 1:34 PM, David Bilenkey at dbilenkey@sympatico.ca wrote:
> So he measured lateral and torsional rigidity, but not vertical compliance
> (which I personally think changes when you tie a wheel). Perhaps if someone
> has space (perhaps Bulgier.net?) I could scan the wheel rigidity testing
> that was done in Bike Tech back in June of '85. I know it's slightly OT.
> These tests were of different spoking patterns and not tied and soldered
> wheels, but it makes for interesting reading.

Damon Rinard didn't test for vertical stiffness, but Francois Grignon did, and Damon included his test data on his site, now on Sheldon Brown's site: http://www.sheldonbrown.com/rinard/wheel/grignon.htm

This testing did not include tied and soldered spokes. However, its results are still interesting since it shows that the measured vertical stiffness can be quite different from perceived stiffness. The most compliant wheel tested was a Specialized trispoke, and the stiffest wheel tested was a Mavic GL330 laced 36H.

I have yet to see any data which suggest that the difference between a vertically stiff and a vertically compliant wheel is perceptible to a rider. The difference in deflection is many times smaller than that of a high-pressure tire. The flex of the fork, stem, handlebars, seatpost, and saddle further mask this difference.

Still, I would be very interested in any test data that anyone is willing to post. It's never too late to learn something new!

Todd Kuzma
Heron Bicycles
LaSalle, IL
http://www.heronbicycles.com/