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steel frame - does it age well?(18 posts)

steel frame - does it age well?laffeaux
Apr 1, 2003 3:49 PM
Does a steel frame with many many miles on it, that has never been crashed (and otherwise treated well), ride as well as it did when it was new? Does the fatigue from years of use add up to make the frame less stiff?

I thought that I had heard that fatigue will show, but wanted to confirm that this is either true or an old wives tale.
re: steel frame - does it age well?teoteoteo
Apr 1, 2003 3:54 PM
I have been told by many wisened elder's of the bike world that old steel frames can get noodly--whether it's true or not is another matter. So I am in the same boat as you.
unlike wine, it ages badlyFender
Apr 1, 2003 4:23 PM
My experience with a steel frame, well taken care off did become more flexiable as time went on. I was losing lots of power on sprints and out of the saddle climbing. The frame had about 10 years of use.

my 2 cents.
re: steel frame - does it age well?gtx
Apr 1, 2003 4:48 PM
I have a lugged SL/SP frame built custom for me in 1989 with 50K + miles on it that still feels new to me. My other steel frames built in 85, 90 and 95 all feel as good as new, too. I think the metal fatique thing with high quality tubing and good build is a bit of a myth (in terms of something you could actually feel), but then again none of the frames I have experience with are very light by today's standards.
Never noticed a difference in 20+ year-old framesSilverback
Apr 1, 2003 4:56 PM
I have a couple of bikes that are more than 20 years old, made of only decent steel (Columbus InExternal and Reynolds 531), both ridden as my main bikes for several years, then used regularly as commuters and beaters. I can't tell any difference from new--which doesn't mean there isn't any, but if there is it's been a small and very gradual change. Like Fender's bike, they go slower than they did 10 years ago...but I'm not blaming the steel.
Absolutly no difference with age...alansutton
Apr 1, 2003 5:28 PM
Steel retains it's elastic modulus (stiffness) unless the frame is damaged.
Absolutly no difference with age...alansutton
Apr 1, 2003 5:30 PM
I think that some of the confusion (and heat...) on this subject
arises because people misunderstand the term fatigue and equate it
with some sort of "work hardening" phenomena.

By definition, metal fatigue and subsequent fatique failure are
well-studied phenomena that occur when metal (steel, aluminum,
etc.) is subjected to repeated stresses within the _elastic_ range
of its deformation. Elastic deformation is defined as deformation
that results in no permanent change in shape after the stess is
removed. Example: your forks "flexing" as the bike rolls over a
cobblestone street.

(an aside... The big difference between steel and aluminum
as a material for bicycles or anything similar is that you
can design the tubes in a steel frame so that they will
NEVER fail in fatigue. On the other hand, no matter how
over-designed an aluminum frame is, it always has some
threshold in fatigue cycles beyond which it will fail.)

This constant flexing of a steel frame that occurs within the
elastic range of deformation must not be confused with the
permanent deformation that happens when the steel is stressed beyond
its elastic limit, (e. g., a bent fork). Repeated permanent
deformation to steel or to any other metal changes its strength
characteristics markedly (try the old "bend a paper clip back and
forth until it breaks" trick).

Because non-destructive bicycle riding almost always limits the
stresses on a frame to the elastic range of deformation, you don't
have to worry about a steel frame "wearing out" over time.

I'm sorry if all of this is old stuff to the majority of this
newsgroup's readers; I just joined a few months ago.
Absolutly no difference with age...Anotheralansutton
Apr 1, 2003 5:33 PM
Another artical:

> I have read accounts of "frames going dead" in cycling literature in
> the past. If you have information that debunks this, I'd like to
> know about it. The explanations I have read claim that the flexing
> of a metal causes it to heat up and harden, making it more brittle.
> Eventually it will break under stress. In fact, I read recently
> that aluminum frames are coming out with warning stickers stating
> "this frame will break someday". I have also read that this happens
> to titanium and steel.

It was in print, therefore it is true! Also known, is that a freshly
washed and polished car runs better. Just the idea that the car is
admirably clean makes this concept appear true for many drivers. The
same psychosomatic mechanism is at work when a bicycle racer thinks it
is time for a new frame. I even suspect that some frame builders
assisted in spreading this idea to improve frame sales.

Metal fatigue and failure occur, but they do not change the elastic
response of the metal. Steel (and of course aluminum and other common
metals) have been metallurgically characterized over more than a
century to a precise understanding. None of this research has shown
the possibility of perceptible change in elastic response from any
stresses to which a bicycle frame might be subjected.

You mention brittleness. Brittleness describes the failure mode of a
material and is not a perceptible unless the material breaks.
Hardness is also not perceptible unless you exceed the elastic limit
and permanently bend the frame, exposing the metal's yield point, the
point at which it no longer rebounds. If not, it springs back
unchanged as do most ceramics such as a dish, or a glass that is
dropped without breaking. If it breaks, it does not bend and none of
the shards show any distortion. It either breaks or it doesn't.
That's brittleness personified.

What escapes the believers of material change is that neither
"softening" or "hardening" effects the elastic modulus of the metal.
A coat hanger and a highspeed steel drill of the same diameter have
the same elastic bending stiffness. For small bending deflections,
both are equally stiff, although the hardened steel can bend farther
than the soft steel and still spring back unchanged. The stress at
which it permanently deforms is the measure of "hardness" of the
metal, not its elasticity.

Classically, when bicycle parts or frames fail, the rider usually
notices nothing before hand. This is true for most thick cross
section parts and often even frame tubes frames. The reason for this,
is that to permit any perceptible change in deflection, all the added
elasticity must come from a crack that has practically no volume. So
the crack would need to open substantially to, by itself, allow
perceptible motion. Since this is not possible without complete
failure, the crack grows in length, but not width, until the remaining
cross section can no longer support the load, at which time it
separates.

> If these ideas have been widely disproven, I'd appreciate knowing
> how. I've read all six parts of the FAQ and did not see it mentioned.

The reason this was not in the FAQ may be that the whole subject is so
preposterous to engineers, metallurgists, and physicists, that they,
the people who might explain it, are generally not inclined to bother
discussing whether "the moon is made of green cheese" or not.

> PS. If what you're objecting to is the use of the word "dead" as
> opposed to brittle and inflexible, I'll grant you that.

The objection is that you present something for which there is no iota
of scientific evidence, nor any even slightly credible explanation, as
though it were fact. It is as though bicyclists have a different
natural world, where the technical laws are entirely different from
all other machinery, and the most per
Thank You Professor Sutton :-) (nm)TREKY
Apr 1, 2003 6:02 PM
this is the answer I wantedlaffeaux
Apr 1, 2003 6:37 PM
And I hope it's the right one. Another independent source to verify this?
"Another independent source to verify this?"Ahimsa
Apr 1, 2003 7:30 PM
"Let's slaughter one of those sacred cows. Steel frames do not go soft. Okay, I said it. So what is metal fatigue? It is a crack resulting from repeated stress cycles above a critical point that we call the fatigue limit. The crack might get started at a stress peak, like a weld or a deep scratch. Stress is extremely high at the tips of cracks, and so the crack grows, just like in a windshield. Eventually, the crack has nearly crossed all the way through the tube, and what's left isn't strong enough, and it breaks. This may seem sudden, but the good news is that a fatigue crack causes so much popping and creaking that a cracked frame will usually give you lots of warning.

Fatigue, however, has no effect on stiffness. Strength degrades, but not stiffness. So, a crack-free steel frame that's 20 years old is as stiff as the day it was made."

-Rick Denney

From "The Truth About Frame Materials, Part 1"
Triathlete Magazine, July 1999

Cheers!

A.
Now that's funny!53T
Apr 2, 2003 6:25 AM
Using a Triathlete Magazine article as an independent source for a metalurgy question. Was it a toss up between that and Mark's Mechanical Engineering Handbook?
re: steel frame - does it age well?toomanybikes
Apr 1, 2003 6:25 PM
I have an old favourite 753 custom build that is 20 years old and has literally tens of thousands of miles on it.

The bike is as good as new, while I have replaced many derailleurs and rims and..... , the frame feels like the day I took delivery.

For a "good" bike - nothing but steel.
I thought that I had "worn out" my frame, until I saw the light.MR_GRUMPY
Apr 1, 2003 8:06 PM
I thought that my classic Bianchi was wearing out. It didn't want to dive through the turns anymore. It felt "funny" going downhill very fast. I was ready to scrap it when I realized the problem. The problem was, that my ass had gotten too fat. Yes, I was suffering from the dreaded "fat guy on a lightweight racing bike" problem. I still ride my Bianchi for training, but I race on a modern, hi-tech, steel frame, that can corner with my 200 lbs.
32 years this summer ...Humma Hah
Apr 2, 2003 8:02 AM
... and good as new.

Just don't leave it outdoors and dirty for very long.

Keeping a little paint on it and maybe spraying the inside of the tubes with an aircraft tubing corrosion preventer won't hurt either.
re: steel frame - does it age well?Fredrico
Apr 2, 2003 9:36 AM
My experience has been that if a steel frame gets noodly with age, it's almost always because it wasn't well brazed when manufactured. The tubing got "cooked" around the lugs. I've seen seat tubes crack right above the BB, and chainstays crack right behind the BB for this reason. The tubing was brittle from too much brazing heat, subjected to high lateral stresses from pedaling, and eventually cracked.

I had a Reynold 531 Puch that seemed to get a little noodly over the years. I speculated it was because the headtube wasn't solidly brazed onto the down tube and top tube. You could see the lugs weren't completely filled in with braze. I gave it to a college student, who said he rode it for several more years. Never found out if it finally gave up, or just stayed noodly.

A carefully brazed frame will last a lifetime, as this thread has already noted. I've been riding a hand brazed SLX frame that had a front end collision with a brick wall 14 years ago. The frame maker bent the fork and head tube back into spec. It has survived several crashes since, but still shows no signs of tube failure, and rides as stiff as it did on the first ride.
the guy who built my steel frame thinks so....Stinky Hippie
Apr 2, 2003 9:43 AM
...I trust him

Feel the gin
only material that rustsjuanteal
Apr 3, 2003 9:03 AM
Unless you live in AZ, it's probably been ridden in the rain and there's probably rust inside.

So, yes, in the long run the frame will become less stiff. Eventually the down tube will open like a can of spagettio's, like mine did.