Re: [CR]Too cheap De Rosa sold on Ebay ... why?

(Example: Framebuilders:Tony Beek)

Date: Sat, 15 Apr 2006 22:38:51 -0700
From: "Steve Maas" <stevem@mail.nonlintec.com>
To: CLASSIC RENDEZVOUS <classicrendezvous@bikelist.org>
Subject: Re: [CR]Too cheap De Rosa sold on Ebay ... why?
References: <20060416021034.80134.qmail@web50207.mail.yahoo.com>
In-Reply-To: <20060416021034.80134.qmail@web50207.mail.yahoo.com>


These tests (which have been on the web for years) have been criticized quite a bit, with justification, I think. The problem is in the way that the frame is mounted, with stress applied in ways that don't correspond to real use. Even so, I think they illustrate a point that is often missed: fundamental properties (in this case, fatigue resistance) of any material shouldn't be viewed as a norm, but as a limiting case. That is, they represent the BEST you can get, not what you ALWAYS get. Improper (or even proper) handling can make things a lot worse; for example, by overheating the downtube when you braze on the lever bosses. Things like this easily become the limiting factor, and the ideal material properties become irrelevant.

In any case, tests like this are for evaluating some particular product, to make sure there are no hidden flaws that might lead to early failure. They are NOT for determining general characteristics of a type of frame; we already know all about that. Many heavily used, decades old, steel frames are still around and still going strong. Plenty of them. Do we really need testing to find out whether they work?

So, gang, don't ditch your DeRosas right away. Or, if you must, you may send them to me for proper disposal. (Well, at least the 58-60 cm ones, especially in red...!)

Steve Maas Long Beach, California

John Barry wrote:
> Interesting reading, but for such a "scientific"
> endeavor, I am immediately struck by two things the
> testers have either overlooked, or simply chosen not
> to mention.
>
> First, no comparison to real-world results was made.
> Second, the sampling population is one - which renders
> any analysis statistically insignificant.
>
> I am unswayed by their findings - and not just because
> I'm a bit of a Luddite.
>
> John Barry
> (6 steel road bikes with 170 total years behind them
> with no signs of failure)
> Mechanicsburg, PA
>
> --- Angel Garcia <veronaman@gmail.com> wrote:
>
>
>>Funny, I was reading a frame stiffness test article
>>just now and read this:
>>"Steel in crisis: De Rosa's SLX quickly breaks after
>>57.000 cycles..."
>>You can read the whole thing at:
>>
>
> http://www.damonrinard.com/EFBe/frame_fatigue_test.htm
>
>>Angel Garcia
>>Verona, Italy
>>
>>
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