brave new world...

John Thompson wrote:
On 2008-08-07, jim beam wrote:

John Thompson wrote:

Who said he was standing? I seldom stand on climbs; only when I'm riding
fixed, really.

that's my point!!! if you want to stand, you want sti/ergo. guys that
say they use bar end shifting aren't standing with their hands on the hoods.

You and Frank are arguing about apples and oranges then. Give it a rest.

no. i'm arguing apples to apples. idiot krygowski keeps trying to
argue prunes.



I did an experiment with an A9 headset. I
installed it on my commuter bike and rode it for 20 years with no
maintenance. Then I opened it up to see how it fared:

http://www.os2.dhs.org/~john/A9.jpg

You can see a little bit of fretting damage on the inner lower race, but
that's about it. I switched lower for upper, repacked and figure I'm
good for another 20 years.

that's not an experiment, that's normal service.

No; "normal service" calls for periodic maintenance.

why? where is that spec written in the manufacturer literature?
answer: it isn't, it's just something you thought you'd say as if it
supports the line you want to take.


I did *nothing* to
that headset for 20 years, and the bike gets ridden in all sorts of
nasty conditions.

so what? most "working" bikes experience long periods of neglect.



...unless you're suggesting a 20-year maintenance period, I suppose.
:-)


no, i'm suggesting you call a spade a spade. deployment is deployment,
not experiment.

Michael Press wrote:
In article
],
Ryan Cousineau wrote:

In article
,
Ozark Bicycle wrote:

On Aug 6, 9:02 am, Ryan Cousineau wrote:
In article
,
Ozark Bicycle wrote:



On Aug 6, 1:44 am, Ryan Cousineau wrote:
In article
,
Ozark Bicycle wrote:
On Aug 5, 9:38 am, Ryan Cousineau wrote:
In article
,
Ozark Bicycle wrote:
* The Quill stem connection between stem and steerer tube
is more subject to corrosion; more so to the extent that
the Al of the quill stem corrodes so much that the steel
steer tube is deformed, rendering the quill stem difficult
or impossible to remove.
Have you ever actually seen this (firsthand) in a well maintained
bicycle?
I have a Pinarello frame currently suffering from this.
To the point "that the steel steer[er] tube is deformed"? Or is the
stem merely 'stuck'?
Semantic quibbling notwithstanding, probably the former.
Why do you assume that to ne the case?
The stem is
stuck, and behaving exactly as Jobst predicts in the FAQ: I could break
it loose so that it will now turn relative to the fork, but I could not
separate the stem from the fork despite considerable applications of
force: the stem would not move vertically relative to the fork.
I have encountered that behavior many times, recently including three
70s-ish vintage bikes which were stored in a barn for 20+ years. Stuck
stems? Yes. Steerer tube(s) deformed by corrosion? Nope!
Well, this is interesting...if the stem is stuck, but not actually
seized to the steer tube, why is it stuck?

Corrosion is the culprit, but not to the extent of deforming the
steerer tube.
I read Jobst's theory as asserting that the corrosion on the inside of
the steertube effectively changes its dimensions above the quill,
causing it to fill the space between the stem and the ID of the steerer.
That's not surprising, given that rust takes up more space than steel.

The quill is actually up against the steerer where it tightens up
(obviously...), so the rust can't expand the ID there (I doubt any rust
really forms there). When you break loose the quill, it's turning freely
in its little space, but can't be pulled out because something is
blocking its way.

Has the aluminum stem rusted? Has the inside of the steer tube rusted?
What is blocking the way?

Like I say, I think you're making a distinction without a difference,
but I've been wrong before, and will be wrong again.

Heck, I'm planning to be wrong sometime tomorrow morning, I've got it in
my calendar and everything,

The Al oxide is what makes the problem. It does not flake
as does Fe oxide, but rather makes an inert, mechanically
tough layer that occupies more volume than the Al.


bull****. it's just as flaky, if not more so than rust. that also
means it's not "tough".

Michael Press wrote:
In article ,
A Muzi wrote:

Ryan Cousineau wrote:
In article
,
Ozark Bicycle wrote:

On Aug 6, 1:44 am, Ryan Cousineau wrote:
In article
,
Ozark Bicycle wrote:



On Aug 5, 9:38 am, Ryan Cousineau wrote:
In article
,
Ozark Bicycle wrote:
* The Quill stem connection between stem and steerer tube
is more subject to corrosion; more so to the extent that
the Al of the quill stem corrodes so much that the steel
steer tube is deformed, rendering the quill stem difficult
or impossible to remove.
Have you ever actually seen this (firsthand) in a well maintained
bicycle?
I have a Pinarello frame currently suffering from this.
To the point "that the steel steer[er] tube is deformed"? Or is the
stem merely 'stuck'?
Semantic quibbling notwithstanding, probably the former.
Why do you assume that to ne the case?

The stem is
stuck, and behaving exactly as Jobst predicts in the FAQ: I could break
it loose so that it will now turn relative to the fork, but I could not
separate the stem from the fork despite considerable applications of
force: the stem would not move vertically relative to the fork.
I have encountered that behavior many times, recently including three
70s-ish vintage bikes which were stored in a barn for 20+ years. Stuck
stems? Yes. Steerer tube(s) deformed by corrosion? Nope!
Well, this is interesting...if the stem is stuck, but not actually
seized to the steer tube, why is it stuck?
Because the steerer is 'mushroomed' where the cone has deformed the
aluminum stem base.

The mushrooming is typically from corrosion of the Al itself,

typically, no it's not - it's mechanical action from the wedge action of
the plug. it /can/ happen, but it's rare.


making a monolithic layer that occupies more volume than the
original Al.

anodizing is monolithic. the kind of gross corrosion that could jam a
stem is far from it.

On Aug 7, 8:32 pm, jim beam wrote:

you're a cheat, a liar and a crappy engineer.

Again, if you restricted yourself to things you actually know about,
your posting volume would drop by 90%. Your accuracy would improve,
too! ;-)

- Frank Krygowski

Frank Krygowski wrote:
On Aug 7, 8:32 pm, jim beam wrote:
you're a cheat, a liar and a crappy engineer.

Again, if you restricted yourself to things you actually know about,
your posting volume would drop by 90%. Your accuracy would improve,
too! ;-)

- Frank Krygowski


restrict myself to what i actually know? ok, that's easy.

1. i actually know you're a cheat because you snip out of context and
you try to red herring away from the facts.

2. i actually know you're a liar because you fabricate untruthful stories.

3. i actually know you're a crappy engineer because you don't know ****
about brinell theory. [among many other things.]

there you go krygowski - 100% accuracy. complete ****ing idiot.