Re: [CR]A chicken and egg question about large and small flange hubs

(Example: Component Manufacturers:Cinelli)

From: <Hughethornton@aol.com>
Date: Tue, 23 Nov 2004 07:52:19 EST
Subject: Re: [CR]A chicken and egg question about large and small flange hubs
To: classicrendezvous@bikelist.org


Unless someone else has already done it, the only way to get a definitive answer is to build wheels with small and large flange hubs using identical rims, identical number of spokes and spoking pattern and tension the spokes to the same or recommended value, fit identical tires and then go try them.

Any other answers will just be opinion, but here FWIW is my opinion:

For radially spoked wheels, the spokes are shorter and at a wider angle with large flanged hubs, therefore more lateral and radial stiffness (high lateral stiffness means, in theory, slightly higher efficiency, especially when riding out of the saddle and swaying the bike from side to side; high radial stiffness means, again in theory, marginally higher efficiency and less spring, i.e. you just might notice bumps and road irregularities a bit more, but in any case, the radial stiffness of the wheel is going to be way higher than the stiffness of the tire)

For tangentially spoked wheels, there really is not a lot of difference in spoke length or sideways angle whatever the flange size, therefore, in my opinion, not much difference in radial or lateral stiffness. I am sure there will be a lot of disagreement with this, but I would only accept the results of a blind test with wheels that are identical except for hub flange size, preferably with laboratory test results to back them up. With a large flange hub rear wheel, the change in spoke tension with the application of drive force will be lower than with a small flange, because of the geater leverage afforded by the flange diameter (i.e. it will have slightly higher rotational stiffness). In theory, this means marginally higher efficiency because of less spoke stretch and a longer life for the spokes.

For any wheel, a stiffer spoke will result in greater lateral and radial stiffness, assuming it is correctly tensioned. Likewise more spokes will give more stiffness. The modern trend towards fewer spokes would seem to indicate that ultimate wheel stiffness is not a big deal and that traditional spoke numbers were more for durability than anything else.

The moral is: ride what looks good (i.e. large flanges and butted spokes because the plain gauge ones look clunky).

Hugh Thornton Cheshire England

tsan7759142@comcast.net writes:


> If double butted spokes are more flexible than straight gauge spokes would
> a
> large flange hub with butted spokes be as comfortable to ride as a small
> flange hub with straight gauge spokes or would I just be destroying any
> advantage gained by the use of the large flange hubs by using such spokes?
> I've sure wasted some money on fancy spokes if this is so. I know this is
> getting pretty close to "How many Angels can dance on the head of a Campy
> drop out screw?" thing I usually eschew but it is running around in my mind
> and I'll be darned if I an figure it out.
> Tom Sanders
> Lansing, Mi