Hincapie's broken fork in Paris-Roubaix



Mike Jacoubowsky wrote:

<snipped>

-Hincapie's failed fork-
>
> The fact that it's unusual, and yet from a product in common use, makes it
> more likely it was a result of the previous accident.
>


Quite so. The question that remains, however, is this: was there
anything unusual about the first (aka, "previous") crash? What might
have transpired that left the bike looking and feeling ridable in the
judgement of a very experienced rider, yet led to a subsequent failure?

My theory: the stem/bar was knocked off center by the crash and someone
(Hincapie?) quickly knocked it back in place. This might have scored
the aluminum fork column, leading to a stress riser which gave way to a
break in the tough conditions of P-R.

I do wonder, why an aluminum fork column on a "commuter" fork?
 
Mike DeMicco wrote:
> What's the point of an aluminum steerer over steel?


Aside from marketing considerations ("the weight! the weight!"), I
can't think of one.


> I can see in larger
> diameters aluminum has a strength to weight advantage over steel, but in
> small diameters? No. I can't help but think if the steerer tube of this
> fork were made of steel then it wouldn't have failed.
>


Personally, I wouldn't go near a fork with an aluminum steerer. IMO,
the risk/benefit ratio is all out of whack.
 
Phil--

Your instructor is right (as far as I know) but he and I are talking
about different things. Since aluminum has no fatigue limit, any stress
cycle creates fatigue--on this, we agree. The phenomenon I'm referring
to entails the compressive residual stress created by bead blasting (or
shot peening, as appropriate). This compressive stress inhibits (but
does not prevent) crack propagation by "squeezing the cracks closed" so
to speak. This phenomenon is reasonably well understood; here's one
reference:

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392002000200002

Here's a link to Independent Fabrications' take on the subject as it
pertains to welded titanium joints:

http://www.ifbikes.com/frames2/faq_shotpeening.shtml

Note that the first reference pertains to media blasting 4340 steel
(not aluminum) but the article abstract does describe the concept in
general terms, to wit:

"With regard to fatigue, it is possible to improve the resistance of a
component with the application of shot peening treatment, whose
compressive residual stresses delay or eliminate the initiation and
propagation of fatigue cracks."

Again, I wouldn't claim that this is necessarily worth doing on
aluminum steerers; my guess is that Hincapie's first crash caused the
steerer to yield and then crack, with the crack propagating until the
bars and stem came off in Hincapie's hands--not at all a fatigue
failure. Of course, until we can collectively examine the steerer,
we're having an angels-on-the-head-of-a-pin discussion. That's totally
unheardof in r.b.t., I know, but I suspect it won't be the last time.
;)

Jason
 
No, Mike, Phil's professor is not wrong--he's talking about a subtly
(but critically) different phenomenon. Phil mentions that fatigue can
occur even if the mean stress never rises above zero, which is just
means that fatigue occurrs in pure compression as well as in tension.
 
Well, if you look in a mechanics of materials (or strength of
materials) textbook, you'll find the equations you need to determine
whether you should use an aluminum or steel steerer in a given
application with a given wall thickness.

It's a little dangerous to generalize about materials this way; if
Hincapie's steerer were very thin steel--say, shim stock--it would
crumple when he put any substantial weight on the bars. One can't
consider the merits of any material in a given application without
considering *all* of the design variables along with those merits.

Jason
 
Mike DeMicco wrote:
> "Phil, Squid-in-Training" <[email protected]> wrote
> in news:FUY_f.715$fG3.27@dukeread09:
>
> > [email protected] wrote:
> >> amakyonin wrote:
> >>> The cyclingnews article on the bike quotes a Trek represe ntative in
> >>> discussing the steerer: "No, it's aluminium; it's been blasted then
> >>> anodized black". Presumably by "blasted" he means bead blasted.


> >> bead blasting causes the outer aluminum to deform plastically,
> >> compressing in the radial direction. (That's why it has that nifty
> >> flat, textured finish). This plastic deformation causes residual
> >> stress, keeping the outer aluminum in a "compressed" state.
> >>
> >> The claim is that this resitual stress improves fatigue life. Since
> >> cracks don't typically grow in regions under compressive stress
> >> (tension is generally what makes cracks propogate) then keeping the
> >> outer "fibers" of aluminum in compression keeps microcracks from
> >> propagating and that's where the improved fatigue life comes from. As
> >> I said, that's the claim. It makes sense to me from a mechanics of
> >> materials perspective, but I have no idea whe ther the theory actually
> >> translates into real-world fatigue-life benefits.

> >
> > It doesn't, according to my instructor from yesterday's lecture. With
> > a mean stress below 0, fatiguing cycles still produce fatigue
> > failures, even if there i s a compressive stress. I'm trying to
> > remember exactly what it was he said, but I'll ask again and find out.
> >

>
> Well, your prof. is wrong. Shot peening has been proven to increase
> fatigue life.


Why do you assume it's the prof's fault? Remember, grasshopper doesn't
remember exactly what was said.

BUT:
(a) bead-blasting is not shot-peening, shot-peening improves fatigue
life, bead-blasting does not. Shot peening is particularly important
before an aluminum part is either anodized or heavily machined.
(b) we don't know whether the steerer actually was bead-blasted, or in
fact shot-peened. I surely hope Trek had the sense to shot-peen such a
crucial part before anodizing it. Just because the mechanic says it was
"blasted" doesn't mean anything.

One of the objections I have to threadless headsets is they clamp the
steerer too tight. With a regular stem, in a crash the bars turn and
can be straightened out with no ill effect. Not necessarily the same
with threadless, depending.

FYI: below first is a manufacturer's blurb about shot peening Ti
frames. It's useful because it distinguishes bead blasting from shot
peening. After is a more general discussion from elsewhere about shot
peening and its uses re machining and anodizing.

---------------------------------------------------------------------------------------------------------
Shot Peening- Why Do We Do It?
Shot peening has 4 major benefits in the crafting of titanium bicycle
frames:

Fatigue life is enhanced significantly increasing the useful life of
the frame The frame is stress relieved so that all of the component
parts work together Surface hardness is enhanced increasing resistance
to scratches Provides an esthetically pleasing finish

Shot peening is a cold working process in which the frame is bombarded
with small spherical metal balls called shot at a precise angle. Shot
act like tiny ball peen hammers and create a uniform dimpled texture on
the surface of the frame. This compacts the outer layer of the
material.

The processes of butting and welding titanium tubes to make a bike
frame are known to create tensile stresses in the frame material.
Tensile stresses make the area in question want to pull itself apart.
This is a bad property to impart to a bicycle frame as any minor notch
or micro crack in the frame will want to propagate and further
compromise the material. The induced tensile stresses are most
concentrated in the heat affected zone - the area of the welds. Thus,
strength is compromised precisely where you would like it to be
greatest.

Shot peening of a welded titanium joint substantially increases both
fatigue strength and fatigue life as compared to the same joint which
is not shot peened. Shot peening imparts what is called residual
compressive stress which counteracts the residual tensile stress, which
is created in the process of cutting, grinding and welding. Typically,
fatigue strength of a welded titanium joint after shot peening is
double that without shot peening. Fatigue life is enhanced by shot
peening to an even greater degree.

By shot peening the frame after it is welded together, we are able to
relieve the stresses in the material providing compressive qualities,
which are known to reduce micro cracking and enhance fatigue life.
Without stress relieving, each of the tubes will retain tensile
stresses which tend to conflict with one another. Stress relieving
allows the component tubes of the frame to work together as designed,
acting as a unified structure rather than a collection of competing
parts.

The shot peening process work hardens the surface of the tube, while
giving it a finely textured surface. These two properties together
create an attractive finish that is highly resistant to scratches. If
scratched, the scratch is harder to see because the surface is
textured. The textured surface glitters in the sun in a manner similar
to that of a pearl paint job.

Some people may confuse shot peening with sand blasting or bead
blasting. At IF, we use sand blasting on our steel frames to remove
contaminants. We also use it impart a microscopic tooth to the surface
of the metal to provide a mechanical bond with the paint. Bead blasting
is used for cosmetic purposes to provide a uniform finish to the
surface of the metal. Neither sand blasting nor bead blasting improve
the mechanical properties of the metal.

Shot peening is used precisely because it improves the performance
characteristics of the finished parts. It is used in the aerospace
industry, in high performance cars and motorcycles, and in light weight
bicycle stems and bars where light weight and high strength are
performance imperatives.

What's the big deal? Don't a lot of frame builders shot peen their
frames?
To the best of our knowledge we are the only titanium frame builder
using the shot peening process. This process should not be confused
with bead blasting, which is used to provide a cosmetic finish to ti
bikes. Any company that claims to bead blast over a shot peened finish
does not understand shot peening. Any type of finish polishing brushing
or bead blasting applied after shot peening negates the benefits of
shot peening.




1. INTRODUCTION
1.1 Shot Peening Described
Shot peening is a cold working process in which the surface of a part
is bombarded with small spherical media called shot. Each piece of shot
striking the material acts as a tiny peening hammer, imparting to the
surface a small indentation or dimple. In order for the dimple to be
created, the surface fibers of the material must be yielded in tension.
Below the surface, the fibers try to restore the surface to its
original shape, thereby producing below the dimple, a hemisphere of
cold-worked material highly stressed in compression. Overlapping
dimples develop an even layer of metal in residual compressive stress.
It is well known that cracks will not initiate or propagate in a
compressively stressed zone. Since nearly all fatigue and stress
corrosion failures originate at the surface of a part, compressive
stresses induced by shot peening provide considerable increases in part
life. The maximum compressive residual stress produced at or under the
surface of a part by shot peening is at least as great as half the
yield strength of the material being peened. Many materials will also
increase in surface hardness due to the cold-working effect of shot
peening.

Benefits obtained by shot peening are the result of the effect of the
compressive stress and the cold working induced. Compressive stresses
are beneficial in increasing resistance to fatigue failures, corrosion
fatigue, stress by corrosion cracking, hydrogen assisted cracking,
fretting, galling and erosion caused by cavitation. Benefits obtained
due to cold working include work hardening, intergranular corrosion
resistance, surface texturing, closing of porosity and testing the bond
of coatings. Both compressive stresses and cold-worked effects are used
in the application of shot peening in forming metal parts.

1.2 Residual Stresses
Residual stresses are those stresses remaining in a part after all
manufacturing operations are completed, and with no external load
applied. These residual stresses can be either tensile or compressive.
For example, a welded joint will contain high magnitude residual
tensile stresses in the heat-affected zone (HAZ) adjacent to the weld.
Conversely, the surface of induction hardened components may contain
residual compressive stresses. In most applications for shot peening,
the benefit obtained is the direct result of the residual compressive
stress produced.

2. MANUFACTURING PROCESSES - EFFECT ON FATIGUE LIFE
2.1 Beneficial Manufacturing Processes
Surface hardening which typically leaves the surface of the part with a
residual compressive stress is a beneficial manufacturing process.
Honing, polishing and burnishing are surface enhancement processes
which remove many of the defects and stress risers which can occur
during other manufacturing operations. Surface rolling will leave the
surfaced in residual compressive stress but is limited to regular
geometries while shot peening, properly controlled, produces the best
results.


2.2 Detrimental Manufacturing Processes
Manufacturing processes are known to have significant effects on
fatigue properties of parts. The effects are either detrimental to
fatigue properties or beneficial. Detrimental processes can include
through-hardening, grinding, abusive machining, plating and welding.
These processes tend to induce residual tensile stresses into the part,
thereby lowering fatigue characteristics. Nontraditional machining,
(ECM, EDM) also results in fatigue debits. In EDM (Electro-Discharge
Machining) a recast layer is produced which can be brittle and notch
sensitive and under residual tensile stress. Fatigue failures can
originate in the recast layer and propagate into the base metal. In ECM
(Electro-chemical machining), the chemical used can attack the grain
boundaries leaving them in a weak, notch sensitive condition.


2.2.1 Grinding
Residual tensile stresses and surface brittleness can be caused by the
generation of high surface temperatures during severe grinding
operations. It has been found that residual tensile stresses created by
grinding can approach the ultimate tensile strength of the material
itself. Residual tensile stress will dramatically reduce the fatigue or
stress corrosion resistance of ground parts. Shot peening after
grinding can overcome the detrimental effect of tensile stresses
induced by severe grinding, as shown in Figure 7.


2.2.5 Anodizing
Anodizing is another application in which shot peening improves fatigue
resistance of coated materials. Benefits similar to those shown for
plating are illustrated in Figure 13 where the high-strength aluminum
base metal was shot peened prior to the hard anodize process.
Fig. 13 The Influence of Hard Anodizing and Shot Peening on the Failure
Strength of Duralumin (LI)
============================================================================
 
In article
<[email protected]>,
"spin156" <[email protected]> wrote:

> Michael Press wrote:
> > > >
> > > > How did it come about that cyclists started to tie and
> > > > solder spokes?
> > >

> .
> >
> > The only practical advantage was on penny-farthing
> > bicycles where a broken spoke of that length was
> > dangerous. Hence tying and soldering to prevent a broken
> > spoke from whipping around dangerously.

>
> So, you asked a question which you already knew the answer to. I
> am curious, what exactly was your purpose in asking this question?


I responded to
<[email protected]>
> I have to
> kind of laugh at all the people that pooh-pooh tying and soldering.
> For something that some experts scoff at, it sure seems to get popular
> every year when this race is run.


Trying to figure out why you are laughing at the people.

--
Michael Press
 
amakyonin wrote:
> The cyclingnews article on the bike quotes a Trek representative in
> discussing the steerer: "No, it's aluminium; it's been blasted then
> anodized black". Presumably by "blasted" he means bead blasted. Are
> either of these two practices sound things to do on an aluminum
> steerer? Is there any value in bead blasting aluminum? I would think
> that this process increases the risk of cracking in stressfull
> conditions as was experienced by Hincapie. I also wonder how much the
> elastomer damper contributed to the failure.


The elastomer damper was on the rear wishbone.
--
Phil, Squid-in-Training
 
D'ohBoy wrote:
> JFT asked OB:
>
>
>>Your comments demonstrate such anti-lawyner, anti-marketing contempt it's
>>nutty. There are times those sentiments might be appropriate, but you
>>seem to relish displaying them. So I ask again -- why the bitterness?

>
>
> Probably the carbon. OB has a thing - he keeps spouting about
> "soul-less" bikes which he, apparently, has extrapolated to the mfr's
> of same.
>
> Plus, lawyers and marketeers ARE frequently agents of Satan.


I, um, saw a movie about that once.

Mark
 
On 11 Apr 2006 19:22:26 -0700, "Ozark Bicycle"
<[email protected]> wrote:

>
>Mike Jacoubowsky wrote:
>
><snipped>
>
>-Hincapie's failed fork-
>>
>> The fact that it's unusual, and yet from a product in common use, makes it
>> more likely it was a result of the previous accident.
>>

>
>Quite so. The question that remains, however, is this: was there
>anything unusual about the first (aka, "previous") crash? What might
>have transpired that left the bike looking and feeling ridable in the
>judgement of a very experienced rider, yet led to a subsequent failure?
>
>My theory: the stem/bar was knocked off center by the crash and someone
>(Hincapie?) quickly knocked it back in place. This might have scored
>the aluminum fork column, leading to a stress riser which gave way to a
>break in the tough conditions of P-R.
>
>I do wonder, why an aluminum fork column on a "commuter" fork?


Why not? Oh yeah, there is a super-remote chance of it failing, and
anything that's lighter and super-remotely less durable is bad, right?

Most importantly, it let's you rag on it.

JT


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John Forrest Tomlinson wrote:
> On 11 Apr 2006 19:22:26 -0700, "Ozark Bicycle"
> <[email protected]> wrote:
>
> >
> >Mike Jacoubowsky wrote:
> >
> ><snipped>
> >
> >-Hincapie's failed fork-
> >>
> >> The fact that it's unusual, and yet from a product in common use, makes it
> >> more likely it was a result of the previous accident.
> >>

> >
> >Quite so. The question that remains, however, is this: was there
> >anything unusual about the first (aka, "previous") crash? What might
> >have transpired that left the bike looking and feeling ridable in the
> >judgement of a very experienced rider, yet led to a subsequent failure?
> >
> >My theory: the stem/bar was knocked off center by the crash and someone
> >(Hincapie?) quickly knocked it back in place. This might have scored
> >the aluminum fork column, leading to a stress riser which gave way to a
> >break in the tough conditions of P-R.
> >
> >I do wonder, why an aluminum fork column on a "commuter" fork?

>
> Why not? Oh yeah, there is a super-remote chance of it failing, and
> anything that's lighter and super-remotely less durable is bad, right?
>
> Most importantly, it let's you rag on it.
>
>


Anything you say, JackAss.
 
On 12 Apr 2006 04:01:07 -0700, "Ozark Bicycle"
<[email protected]> wrote:

>
>John Forrest Tomlinson wrote:
>> On 11 Apr 2006 19:22:26 -0700, "Ozark Bicycle"
>> <[email protected]> wrote:
>>
>> >
>> >Mike Jacoubowsky wrote:
>> >
>> ><snipped>
>> >
>> >-Hincapie's failed fork-
>> >>
>> >> The fact that it's unusual, and yet from a product in common use, makes it
>> >> more likely it was a result of the previous accident.
>> >>
>> >
>> >Quite so. The question that remains, however, is this: was there
>> >anything unusual about the first (aka, "previous") crash? What might
>> >have transpired that left the bike looking and feeling ridable in the
>> >judgement of a very experienced rider, yet led to a subsequent failure?
>> >
>> >My theory: the stem/bar was knocked off center by the crash and someone
>> >(Hincapie?) quickly knocked it back in place. This might have scored
>> >the aluminum fork column, leading to a stress riser which gave way to a
>> >break in the tough conditions of P-R.
>> >
>> >I do wonder, why an aluminum fork column on a "commuter" fork?

>>
>> Why not? Oh yeah, there is a super-remote chance of it failing, and
>> anything that's lighter and super-remotely less durable is bad, right?
>>
>> Most importantly, it let's you rag on it.
>>
>>

>
>Anything you say, JackAss.


I asked a question too. Why not?

JT

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Visit http://www.jt10000.com
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John Forrest Tomlinson wrote:
> On 12 Apr 2006 04:01:07 -0700, "Ozark Bicycle"
> <[email protected]> wrote:
>
> >
> >John Forrest Tomlinson wrote:
> >> On 11 Apr 2006 19:22:26 -0700, "Ozark Bicycle"
> >> <[email protected]> wrote:
> >>
> >> >
> >> >Mike Jacoubowsky wrote:
> >> >
> >> ><snipped>
> >> >
> >> >-Hincapie's failed fork-
> >> >>
> >> >> The fact that it's unusual, and yet from a product in common use, makes it
> >> >> more likely it was a result of the previous accident.
> >> >>
> >> >
> >> >Quite so. The question that remains, however, is this: was there
> >> >anything unusual about the first (aka, "previous") crash? What might
> >> >have transpired that left the bike looking and feeling ridable in the
> >> >judgement of a very experienced rider, yet led to a subsequent failure?
> >> >
> >> >My theory: the stem/bar was knocked off center by the crash and someone
> >> >(Hincapie?) quickly knocked it back in place. This might have scored
> >> >the aluminum fork column, leading to a stress riser which gave way to a
> >> >break in the tough conditions of P-R.
> >> >
> >> >I do wonder, why an aluminum fork column on a "commuter" fork?
> >>
> >> Why not? Oh yeah, there is a super-remote chance of it failing, and
> >> anything that's lighter and super-remotely less durable is bad, right?
> >>
> >> Most importantly, it let's you rag on it.
> >>
> >>

> >
> >Anything you say, JackAss.

>
> I asked a question too. Why not?
>


Does anyone use the nickname "Osmium Head" (or "Ozzy", for short) in
referring to you? ;-)
 
On 12 Apr 2006 05:22:44 -0700, "Ozark Bicycle"
<[email protected]> wrote:

>
>John Forrest Tomlinson wrote:
>> On 12 Apr 2006 04:01:07 -0700, "Ozark Bicycle"
>> <[email protected]> wrote:
>>
>> >
>> >John Forrest Tomlinson wrote:
>> >> On 11 Apr 2006 19:22:26 -0700, "Ozark Bicycle"
>> >> <[email protected]> wrote:
>> >>
>> >> >
>> >> >Mike Jacoubowsky wrote:
>> >> >
>> >> ><snipped>
>> >> >
>> >> >-Hincapie's failed fork-
>> >> >>
>> >> >> The fact that it's unusual, and yet from a product in common use, makes it
>> >> >> more likely it was a result of the previous accident.
>> >> >>
>> >> >
>> >> >Quite so. The question that remains, however, is this: was there
>> >> >anything unusual about the first (aka, "previous") crash? What might
>> >> >have transpired that left the bike looking and feeling ridable in the
>> >> >judgement of a very experienced rider, yet led to a subsequent failure?
>> >> >
>> >> >My theory: the stem/bar was knocked off center by the crash and someone
>> >> >(Hincapie?) quickly knocked it back in place. This might have scored
>> >> >the aluminum fork column, leading to a stress riser which gave way to a
>> >> >break in the tough conditions of P-R.
>> >> >
>> >> >I do wonder, why an aluminum fork column on a "commuter" fork?
>> >>
>> >> Why not? Oh yeah, there is a super-remote chance of it failing, and
>> >> anything that's lighter and super-remotely less durable is bad, right?
>> >>
>> >> Most importantly, it let's you rag on it.
>> >>
>> >>
>> >
>> >Anything you say, JackAss.

>>
>> I asked a question too. Why not?
>>

>
>Does anyone use the nickname "Osmium Head" (or "Ozzy", for short) in
>referring to you? ;-)


Not that I'm aware of -- what does that mean?

And why not aluminum steerers on a commuting bike?

JT

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John Forrest Tomlinson wrote:
> On 12 Apr 2006 05:22:44 -0700, "Ozark Bicycle"
> <[email protected]> wrote:
>
> >
> >John Forrest Tomlinson wrote:
> >> On 12 Apr 2006 04:01:07 -0700, "Ozark Bicycle"
> >> <[email protected]> wrote:
> >>
> >> >
> >> >John Forrest Tomlinson wrote:
> >> >> On 11 Apr 2006 19:22:26 -0700, "Ozark Bicycle"
> >> >> <[email protected]> wrote:
> >> >>
> >> >> >
> >> >> >Mike Jacoubowsky wrote:
> >> >> >
> >> >> ><snipped>
> >> >> >
> >> >> >-Hincapie's failed fork-
> >> >> >>
> >> >> >> The fact that it's unusual, and yet from a product in common use, makes it
> >> >> >> more likely it was a result of the previous accident.
> >> >> >>
> >> >> >
> >> >> >Quite so. The question that remains, however, is this: was there
> >> >> >anything unusual about the first (aka, "previous") crash? What might
> >> >> >have transpired that left the bike looking and feeling ridable in the
> >> >> >judgement of a very experienced rider, yet led to a subsequent failure?
> >> >> >
> >> >> >My theory: the stem/bar was knocked off center by the crash and someone
> >> >> >(Hincapie?) quickly knocked it back in place. This might have scored
> >> >> >the aluminum fork column, leading to a stress riser which gave way to a
> >> >> >break in the tough conditions of P-R.
> >> >> >
> >> >> >I do wonder, why an aluminum fork column on a "commuter" fork?
> >> >>
> >> >> Why not? Oh yeah, there is a super-remote chance of it failing, and
> >> >> anything that's lighter and super-remotely less durable is bad, right?
> >> >>
> >> >> Most importantly, it let's you rag on it.
> >> >>
> >> >>
> >> >
> >> >Anything you say, JackAss.
> >>
> >> I asked a question too. Why not?
> >>

> >
> >Does anyone use the nickname "Osmium Head" (or "Ozzy", for short) in
> >referring to you? ;-)

>
> Not that I'm aware of -- what does that mean?
>


Please! I'm gonna die laughing!


> And why not aluminum steerers on a commuting bike?
>
>


See if you can figure it out for yourself, Ozzy.
 
Ozark Bicycle wrote:
> Sally wrote:
> > "Mike Jacoubowsky" <[email protected]> wrote in
> > news:[email protected]:
> >
> > > The official press release, from Zapata Espinosa at Trek, 4/10/06

> >
> > That's a pretty quick CYA.

>
> That's what all those lawyers on retainer are for.
>
> And didn't ya just love Bruyneel's kiss-the-sponsor's-ass statement?


gee, ever figure out what Trek gives to Discovery as a sponsor? This is
NOT a design problem, nothing that points any finger at Trek or any
other manufacturer that has something break at P-R...this didn't happen
on the smooth roads of the TdF ya know. I am amazed at all these posts
like it is something to be amazed and worried about. What stuff do any
of you ride? has it ever been used in P-R? If it has it has
broken....this just happened to be on TV on the favorite's bike...

>
> This fork-failure/crash/injury must be really embarrassing to Trek
> Corporate.


In 2 weeks it will be water cooler talk and peple will still buy
Treks...
>
> > And without any update or concern about George's
> > condition.
 
Michael Press wrote:
> In article
> <[email protected]>,
> "spin156" <[email protected]> wrote:
>
> > Michael Press wrote:
> > > > >
> > > > > How did it come about that cyclists started to tie and
> > > > > solder spokes?
> > > >

> > .
> > >
> > > The only practical advantage was on penny-farthing
> > > bicycles where a broken spoke of that length was
> > > dangerous. Hence tying and soldering to prevent a broken
> > > spoke from whipping around dangerously.

> >
> > So, you asked a question which you already knew the answer to. I
> > am curious, what exactly was your purpose in asking this question?

>
> I responded to
> <[email protected]>
> > I have to
> > kind of laugh at all the people that pooh-pooh tying and soldering.
> > For something that some experts scoff at, it sure seems to get popular
> > every year when this race is run.

>
> Trying to figure out why you are laughing at the people.
>
> --
> Michael Press


Sorry, Michael, I'll try explaining myself a little differently.
There are many professional cyclists that obviously believe that it is
of value to them (in the P-R race, at least). Apparently they know
something than many of the so-called experts - most of whom are not
professional cyclists (I'm saying this as I don't see any of the well
known names in pro racing contributing to this forum on a regular
basis). I think that is amusing - and, at the same time unfortunate
- that people can be so certain of themselves that they are not even
willing to admit it's just their opinion, or theory.

I'm disappointed that you didn't just ask me what you wanted to know in
the first place and that you felt it necessary to bait me.

The amount of acid that courses through the veins of this forum is
incredibly sad. When I first found r.b.t. I thought that I had
found a good source of information where people could have resonable
discourse on bicycles. I'm here primarily to learn some things and
make a contribution when I can. What I am learning (more than the
technical stuff I am looking for) is just how rude people are. I
really don't get all the bitterness that surfaces here. The
sniping, namecalling, personal attacks, and just_plain_nastiness is
incredible. It's amazing that people who are presumably adults carry
on in this fashion. The saddest things in our world today are that
people are dying in wars, starving, dying from diseases and natural
disasters on a continuing basis.
Yet, somehow hate of war has managed to permeate down to the level of
this forum. If you can't even show some respect for the fellow
members of an internet forum, how can anyone complain about how the big
politicians are running the world (this seems to be a favorite off
topic thread here). It's completely hypocritical. This is
easy. Start with yourself and show respect for the people that are
around you and maybe, just maybe, that will grow into something larger.
As the expression goes, "pay it forward". Agree to disagree, and
try to do it with some modicum of respect. It's not that hard.

I, for one, am committed to doing my small part.

Regards,
-- Bill
 
Qui si parla Campagnolo wrote:

<snipped>

-on Hincapie's broken fork at P-R-

> This is
> NOT a design problem, nothing that points any finger at Trek or any
> other manufacturer that has something break at P-R..


Those were my thoughts, too, especially when there was some speculation
that Hincapie's bike was fitted with a 'special' steerer tube in an
attempt to shave a few grams. Now, however, it seems this was a
box-stock Bontrager Satellite fork with it's stock aluminum steerer
tube.

This makes me wonder: 1) what was the nature of the first crash that
left the bike seemingly looking and feeling ridable? 2) would a steel
steerer tube have fared better? 3) what is the wisdom of putting an
alumimum steerer tube on a fork that is marketed to commuters? 4) would
a seemingly routine crash during a commute make this fork vulnerable to
failure at a later date over the random rough roads, potholes, etc.
encountered by many commuters.
 
Ozark Bicycle wrote:
([email protected] wrote):

> > Crashed aluminum?
> >

> Could you clarify your question?


I broke a steel fork that had been crashed before I owned it. While
motorpacing, the right fork blade snapped off about four inches below
the crown/blade joint.

One very useful "lesson" to be learned from this is that headsets
*don't* "loosen up" that much (ref. Hincapie quote). That's what I
thought, too, while in the warmup for a motorpace ride. Far too much
movement for anything non-catastrophic, in retrospect, and I even put
my front brake on to stop! When the skewer was loosened, clang went the
fork blade on the ground. Since I wasn't severely injured or dead, it
was funny. Ha ha.

There was a track rider on the Nat. circuit a few years ago who had a
steerer tube pull out of a fork crown, in the middle of a mass start
event at Alkek (Houston V-drome). I forget the name, he rode further
than necessary, too, before pulling into the infield, and clanging one
himself-- tire, forks, crown all together but not attached to the bike
any more. Yup, "I thought my headset had loosened up" (approx.,
accurate quote). Well, in a way, it had...

Your point about the stem scoring the steer tube on Hincapie's bike (if
it was indeed twisted and banged back straight to continue the race)
sounds like a real possibility, another useful "fallout" from this
event.

Is there a steel-steerer carbon fork in production, or available
used/NOS?

Sooo... what's with the "jackass" and "learn to read, take your time"
BS? Were you raised in the Ozarks, or something? --D-y
 
spin156 <[email protected]> wrote:
> There are many professional cyclists that obviously believe that

^^^^^^^

> it is of value to them (in the P-R race, at least).
> Apparently they know something than many of the so-called experts

^^^^

Maybe you want to elaborate on how you come from "believe" to
"know", besides you opinion.


> I think that is amusing - and, at the same time unfortunate - that
> people can be so certain of themselves that they are not even
> willing to admit it's just their opinion, or theory.


Obviously you're eager to contribute quite a lot to that amusement...


--
MfG/Best regards
helmut springer
 

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