Re: [CR]Italian use of Reynolds tubes Was: Gitane vs Peugeot

(Example: Framebuilders:Cecil Behringer)

From: <"brianbaylis@juno.com">
Date: Thu, 4 Aug 2005 13:57:20 GMT
To: jerrymoos@sbcglobal.net
Subject: Re: [CR]Italian use of Reynolds tubes Was: Gitane vs Peugeot
cc: classicrendezvous@bikelist.org
cc: classicrendezvous@bikelist.org

Jerry,

Frames don't go out of alignment from rideing either, as you suspect. The misalignment would have to be severe; but a realigned frame will probably feel better. Misaligned frames were either built that way or they were damaged somehow.

Brian Baylis La Mesa, CA Ah, the myths that plague us as framebuilders.


-- Jerome & Elizabeth Moos wrote:


I only took undergraduate materials science courses, but I too believe that the idea that a steel frame "goes soft" with age contradicts all the applicable science. One explanation I have heard that makes more sense is that what actually happens is that frames goes out of alignment over a few years.

Frankly, I don't quite understand that either, as to deform a steel tube you should have stress it beyond its elastic limit, which should be far beyond any force applied to a bicycle frame, except in a crash. Maybe the loss of alignment actually occurs at the lugs by deforming the softer brass or silver brazing material. Or perhaps I underestimate the stress that can be applied to small tube cross-sections like at the ends of the forks and stays just above the DOs. In any case, I can much more readily believe a frams feels dead due to misalignment than because the steel tubes themselves "went soft".

I've heard it reported that "dead" steel frames were restored to "lively" feel by a proper, thorough, realignmant. The problem with proving this is that both "dead" and "lively" are subjective. But at least this version of events doesn't seem to directly contradict scientific principles.

Regards,

Jerry Moos Houston, TX

ternst <ternst1@cox.net> wrote: That is correct. I realize and understand the contradiction. I also suspect the difference in the "season" of wear is not a big amount, cause it would be difficult to quantify, but the feel is there and it's not imagination, this isn't Salem hysteria. These are serious people and that small feel is all that is needed to give pause because of the level of performance. Whether one speeds down the Alps, Rockies, or Sierras at 60mph the riders know. Obviously, regular riding at 15 - 25 mph, and folks who tell me they apply brakes and don't go over 30mph downhill probably are not going to have this experience. But it's the hard riders, as in car racing the competition drivers, who determine the limits for the improvement of product to the general sport and touring public. Testing goes so far, but NASA needs a little help out there, too. All this absolutely good discussion on blades, shape, profile, tube mix, etc., is outstanding to read and mull over, but until it's brazed up and ridden under various loads, speeds, and conditions, we don't really know. We're way ahead of the old timers in that we think it should be such or such but it still has to be ridden. That's why two bikes, put together in sequence by the same builder WILL FEEL AND RIDE ever so differently, and the owner of the matched pair with identical equipment will always have a favorite of the pair. The old track riders 80 years ago said it, and it hasn't changed today. Ted Ernst Palos Verdes Estates, CA


----- Original Message -----
From: "Ken Wehrenberg"
To:
Cc:
Sent: Wednesday, August 03, 2005 10:20 AM
Subject: Re: [CR]Italian use of Reynolds tubes Was: Gitane vs Peugeot


> Ted and list:
>
> I know that in the CO mountains, we had racers, esp some who had been in
> Europe, "test" their frames after a season or so by applying foot pressure
> to the top of six-o'clock-positioned left crank while holding bike firmly
> at handlebars and saddle. They claimed that usage could/would cause the
> frame to go "dead" and thus necessitate its replacement, sometimes with
> the same maker's geometry and frame material.
>
> Flies totally in the face of what I learned in graduate level materials
> science courses, though....
>
> Ken Wehrenberg, Hermann, MO