[email protected] wrote:
> Ed Pirrero wrote:
> >
> >
> > These are not one-off designs. The raw materials to make the tests are
> > trivially inexpensive for the manufacturers of the items in question.
>
> I didn't say they were one-off designs.
That was the example you used.
> In many cases, it comes down to a judgement about most efficient use of
> resources. Is it easier to set up carefully controlled lab tests to
> verify an obvious problem, or is it easier to simply and easily fix it?
> In this case, the fixes are trivially easy.
Unless, of course, there is no problem to fix. Other than the
hypothetical one.
> >
> > But when there is a question of safety of design, doing some small
> > amount of destructive testing can completely answer questions without
> > being excessively expensive.
>
> I can draw up a revised dropout design, or a revised disk caliper
> mount, in less than an hour.
So can I, and I'm not even an engineer. But if the revision is not
needed, then the redesign is not required.
> To develop a test to prove the obvious -
> that these axles can slip dangerously under certain conditions
There's that word again: danger. And yet, with no actual proven cases
of injury, the loaded language is trotted out.
> - would
> take at least a week.
Actually, I thought up a test in my head in about thirty seconds. It
would actually require someone to do some real work, instead of tapping
on a keyboard, but I guess that's really the big impediment here,
right? Sheer laziness.
> IMO, the only reason a company wouldn't do the
> easy re-design would be the complications coming from our liability
> system - an admission of liability on the forks & brakes on the market.
Everyone moving to a QR20 sort of system? A system that already
exists? A system that could be marketed as a "fork stiffening"
redesign?
Give me a break.
> > > > > There will always
> > > > > be people so welded to their own view that no amount of evidence and
> > > > > logic will suffice.
> > > >
> > > > A lovely strawman. Knock it down!
> > >
> > > You seem very confused about the definition of a "strawman argument."
> >
> > Actually, I'm quite clear. You are implying that I am welded to my own
> > view, and that no amount of evidence and logic will suffice.
>
> Yes, I believe that's true.
What you *believe* is irrelevant. I told you what my position was.
Mischaracterizing it is engaging in the logical fallacy of the
strawman.
> But that wasn't a strawman argument. You
> don't understand the definition of the term.
LOL. Of course I do. I gave a paraphrased definition with your
posting as an example.
Feel free to prove me wrong, if you dare.
> [regarding QRs loosening under the lateral forces imposed by the disk,
> just as industrial fasteners loosen under lateral forces:]
> > > > > > Another presumption. It *might*. But *does it*? We don't know,
> > > > > > because nobody has actually done any controlled testing.
> > > > >
> > > > > Our of curiosity, Ed, why do you think that well known mechanism for
> > > > > loosening of industrial threaded fasteners would _not_ apply to
> > > > > fasteners with far less locking power and far greater transverse loads?
> > > >
> > > > Who says they don't?
> > > >
> > > > Oh, that's right, another strawman.
> > >
> > > Again, you seem very confused about that definition.
> >
> > Actually, it is you who are confused. Again, you state clearly that I
> > have a particular position - a position that I don't actually have, in
> > order to paint a rhetorical picture.
>
> 1) The mechanism of such loosening is well known.
Indeed. The bolt science website describes it.
> 2) This situation
> has all the earmarks of the physics that loosens such fasteners.
A nicely weaselled comment. It does have the *earmarks*. But it
hasn't been shown that it happens but even in the very smallest
minority of cases - such a small sample as to be indistinguishable from
statistical noise.
Maybe it happens. What's the comparison between disk brakes and the
control group?
> 3)
> You implied QRs might not loosen here, despite all those earmarks.
Since we have some folks who have said theirs don't loosen, there's a
chance that they don't. Oh, wait - that data doesn't count, right?
That doesn't even count the thousands upon thousands that have not
reported either way.
> 4)
> I asked why you believed they might not - that is, what might prevent
> it.
I don't "believe" anything about the system. I have stated, a bunch of
times for you Alzheimers types, that the system seems to defy portions
of the hypothesis at will. This implies some additional complication
unaccounted-for in the hypothesis.
> Again, that does _not_ fit the definition of a strawman.
It does, because you are assigning to me beliefs that I do not hold.
No matter how you attempt to weasel out of it, that is what you are
doing.
I'm am not offering a counter-hypothesis. I'm not going to. I'm using
the available evidence as supporting data to show shortcomings *in the
current hypothesis.* If you have a problem with that data set, you may
certainly show how it is not applicable.
> > > > Or maybe, just maybe, not everything is known about the system. It
> > > > could be that James is 100% correct. I don't discount that possiblity,
> > > > because I understand how hypotheses work. But it sure would be nice to
> > > > see SOMETHING other than supposition and conjecture.
> > >
> > > You mean like reports of front wheels popping out on hard application
> > > of a rear-mounted disk brake?
> >
> > Reports? I've only seen conjecture on a couple of incidents where what
> > really happened is still unknown.
>
> The point is, the wheels popped out. They were reported. That makes
> them "reports."
Nice weasel. What reports are you talking about?
> > > Or you mean like multiple reports of QR skewers being carefully
> > > adjusted and fastened, then becoming loose on their own after bumpy
> > > braking with a rear mounded disk brake?
> >
> > And how many incidents of bikes with rim brakes have had the same thing
> > happen?
>
> Zero, AFAIK.
Of course, you haven't even bothered to look. When I was riding my
cruiser bike, I once came off a curb and had the wheel come out of one
of the drop outs. Turned the bars and threw me right onto the
sidewalk. That bike had no front brake at all.
There's one.
> If you pretend otherwise, say so.
I don't pretend - it's happened to me, before disk-brake bikes even
existed. And I've had other front wheel incidents after transport that
were quite obviously user error.
All with rim brakes.
> If not, quit asking
> distracting, hypothetical and irrelevant questions.
LOL. You do know what a "control group" is, right, Frank? If not,
then we're done here.
> Meanwhile, you
> asked for something other than conjecture, and I'm giving it to you.
Actually, you have offered no additional data. Where's the statistics?
The numerical data from the actual experiments? What, you don't have
any? Just rehashed opinion, and not even original opinion? No, you're
still engaging in the very same conjecture.
> > > Or you mean standard engineering calculation techniques showing forces
> > > in directions backwards from the original design intent of fork
> > > dropouts?
> >
> > That's part of the original hypothesis, and isn't more convincing upon
> > multiple repetition.
>
> Again, "convincing" depends on the background knowledge of the reader.
No, it doesn't. The force exists. Whether or not it's "dangerous" has
not yet been answered. Circumlocution doesn't impress me. Nor does ad
hominem logical fallacy.
[The "lack of background knowledge" part is the ad hominem.]
> Some people just won't understand, and thus won't be convinced.
Wrong. Some people take the entire data set and look at it as a whole,
instead of picking the data that suit their biases.
> (I notice that many of the
> people arguing against you are engineers.)
Logical fallacy: appeal to authority.
> > > But frankly, I think it's
> > > just because you've staked out your position so strongly that you now
> > > require extreme (and expensive) levels of "proof."
> >
> > Yet another strawman. Imbuing me with some sort of attitude that I
> > just don't have. But hey, they are fun to knock down...
>
> 
Wow! Talk about ignoring the evidence!
Non sequitur. Less rhetoric, and more "technical". You do realize
that anyone who has taken a logic class can see right through this
****, right, Frank?
E.P.
