CPSC judgement on disk brakes and QR forks - Page 2

Gary Young wrote:

> It's a little hard to judge the adequacy of the response without knowing what information you put
> before them. Could you post your letter to the CPSC here? Then we might be able to suggest ways to
> beef it up.

Can't remember in detail, it was just the sort of stuff that has been discussed here, together with
some description of one or two of the crashes I've heard about. One minor difficulty is that they
didn't seem capable of considering the generic problem but were only geared up to handle a specific
complaint from a victim.

> The CPSC is supposed to be above politics, but perhaps the problem is that your letter didn't come
> from a U.S. citizen. Those of us who live in the U.S. should start sending letters. Is there a
> particular person you dealt with there?

Yes, the CPSC actually asked me to encourage others to add their experiences and I did suggest this
some time ago (maybe not here though). Of course got plenty of criticism from those who said I was
'scaremongering' and exaggerating the problem...but as we see, without such support from others, the
CPSC believes that quite literally there is no problem to investigate.

If anyone wishes to write to express their views, the CPSC person responsible for this is JDeMarco
(at) cpsc (dot) gov. I would appreciate a copy (preferred address on my web page, although the
hotmail one is checked occasionally) just so I can keep track of anything useful. I haven't yet
bothered replying to his recent letter but I suppose I should let him know what I think of his
performance. He might also be interested to hear that a couple of victims are taking legal advice on
the matter, since according to him such people don't exist.

> I'm also curious if you've gotten any responses in other countries.

I didn't bother contacting anyone else directly, since the manufacturers are all based in the USA
and the CPSC had a convenient web site and email address... It has been reported that the Australian
authorities were looking into it, but that was months ago. Also I heard that a Trading Standards
Officer in the UK actually advised a retailer to stop selling forks, but this was off the record and
an isolated incident that went no further.

James

In article <bfbe6ed3.0308280706.cc59a26@posting.google.com>, garyyoung3@hotmail.com (Gary
Young) wrote:

> The CPSC is supposed to be above politics

The CPSC on which planet? The one in the US is terminally embroiled in politics, and those politics
change like the wind with the various Administrations. This Administration is determined to remove
as much government interference from business as possible (while maximizing big government
interference into people's personal lives). You can be sure that the CPSC will be rendered as
powerless as possible for the next 6 years.

In article <jsh3b.29293$cj1.15508@fed1read06>, "Mike S." <mikeshaw2@coxDOTnet> wrote:

> > If no one knew about it, what would prompt someone to do something?
> >
> > Joe Riel
>
> If noone knows, is there a really a problem?

Yes. Virnigia, there really is a problem. Even if you lack the wit to understand it.

> Seems that someone would know if they had a problem with their dropouts, and the LBS would start
> to hear about it, and then the manufacturers would start to get warranty claims, and...

Not in this case because "everyone knows" that front wheels only fall out of the fork as a result of
operator error, and that if it happens to you it's your own damned fault. Unfortunately this is just
more ignorance and misplaced lore.

> Sounds to me like some little boy's calling "wolf."

A call that's had some independent verification within the industry.

In article <ek5skv0qe8ts5crocn0dark2hptruj21ra@4ax.com>, Doug Taylor
<taylordw@choiceonemail.com> wrote:

> "Mike S." <mikeshaw2@coxDOTnet> wrote:
>
> >Sounds to me like some little boy's calling "wolf."
>
> Or Chicken Little crying that the sky is falling.
>
> The evidence to date simply does not support labeling disc brakes used with forks having quick
> releases as a substantially product hazard.

Actually, the evidence is precisely contrary to your clam, and stands in support of Annan's
analysis. But feel free to continue to deny reality. And do check those QRs occasionally.

> It is a rare and obscure problem that happens infrequently (if at all) and interests only bike
> geeks who post on usenet.

It interests anyone who uses this equipment.

> Cost benefit analysis says hold 'em.

Until the costs include a hospital stay and facial reconstruction surgery.

"S. Anderson" wrote:
>
> <jobst.brandt@stanfordalumni.org> wrote in message
> news:SRa3b.15874$dk4.530160@typhoon.sonic.net...
> >
> > What strike me about this is that it is a typical NASA "culture" approach to the subject. If you
> > read the item on NASA denial at:
> >
> >
> http://www.sfgate.com/cgi-bin/articl...003/08/26/nati onal0151EDT0426.DTL
> >
> > You could easily replace NASA with CPSA and the glove would fit.
> >
> > I see we must wait for one of the victims to bring a multi-million $ damage claim against the
> > industry. CPSA should be culpable as well.
> >
> > Jobst Brandt jobst.brandt@stanfordalumni.org Palo Alto CA
>
> I think NASA is its own little universe. I'm not sure that the situation that exists there, an
> organization that is dependent on government funding for its existence, can necessarily be
> translated to this situation. But to be sure, most large corporations behave in a similar fashion
> to the CPSA in this case. Certainly the auto industry does. It will boil down to the cheaper
> option: lawsuits or revising the product to make it safe. As far as most corporations go, a human
> life has a price. And if that price is lower than fixing the problem, the problem usually doesn't
> get fixed. Sad as that may be.

Hey, if tort law "reform" passes, even the civil court route might fail. Caveat emptor.

"gwhite" <gwhite@ti.com> wrote in message news:3F4E9267.2777F31B@ti.com...
>
>
> "S. Anderson" wrote:
> >
> > <jobst.brandt@stanfordalumni.org> wrote in message
> > news:SRa3b.15874$dk4.530160@typhoon.sonic.net...
> > >
> > > What strike me about this is that it is a typical NASA "culture" approach to the subject. If
> > > you read the item on NASA denial at:
> > >
> > >
> >
http://www.sfgate.com/cgi-bin/articl...ve/2003/08/26/ nati
> > onal0151EDT0426.DTL
> > >
> > > You could easily replace NASA with CPSA and the glove would fit.
> > >
> > > I see we must wait for one of the victims to bring a multi-million
$
> > > damage claim against the industry. CPSA should be culpable as
well.
> > >
> > > Jobst Brandt jobst.brandt@stanfordalumni.org Palo Alto CA
> >
> > I think NASA is its own little universe. I'm not sure that the
situation
> > that exists there, an organization that is dependent on government
funding
> > for its existence, can necessarily be translated to this situation.
But to
> > be sure, most large corporations behave in a similar fashion to the
CPSA in
> > this case. Certainly the auto industry does. It will boil down to
the
> > cheaper option: lawsuits or revising the product to make it safe.
As far as
> > most corporations go, a human life has a price. And if that price
is lower
> > than fixing the problem, the problem usually doesn't get fixed. Sad
as that
> > may be.

I met Hal Stratton, the Chairman of the CPSC, a few months ago. I was prepared to hate him because
he is a Bush appointee, but he seemed like a nice guy who takes his job very seriously. But his job
is a big one, and the CPSC has a tiny budget. In fact, there should be five commissioners, but only
three spots have been funded. It is not a billion dollar agency like NASA. I does not own real
estate in Florida or employ rocket scientists or maintain spaceships. Hal has a lot to worry about
besides after market bicycle brakes -- like things that blow up and catch on fire and really hurt
people besides Missy Giove.

> Hey, if tort law "reform" passes, even the civil court route might fail. Caveat emptor.

Class action and tort reform is needed, and the reform I have seen proposed would not prevent most
products-related law suits. It usually involves damages caps and exclusive federal jurisdiction over
certain suits, and most proposed reform at the local level involves doctors who have been sued out
of delivering babies. It will never pass anyway, because the trial lawyers have more money than
industry -- plus they get Erin Brockovich to display her breasts and talk about the importance of
the jury system -- when her famous case was decided by an arbitrator (go figure). -- Jay Beattie.

"Jay Beattie" <jbeattie@lindsayhart.com> wrote in message news:vkt9m9konbqeca@corp.supernews.com...
>
>
> > Hey, if tort law "reform" passes, even the civil court route might fail. Caveat emptor.
>
> Class action and tort reform is needed, and the reform I have seen proposed would not prevent most
> products-related law suits. It usually involves damages caps and exclusive federal jurisdiction
> over certain suits, and most proposed reform at the local level involves doctors who have been
> sued out of delivering babies. It will never pass anyway, because the trial lawyers have more
> money than industry -- plus they get Erin Brockovich to display her breasts and talk about the
> importance of the jury system -- when her famous case was decided by an arbitrator (go figure). --
> Jay Beattie.
>
>

Interesting. I think it's commonly thought up here (Canada) that the civil legal system is out of
control in the States. We often read things about auto lawsuits (I'm in the engineering business)
and wonder which way is up. You know, the usual millions awarded some drunk driver who fell asleep
at the wheel at 140mph and crashed into a bridge abutment whose family argues that the car should
have protected the driver against all foreseeable impacts, or someone with a "back injury" who sues
for salary and the right to never work again due to this injury etc etc. Is that the common thought
in the States as well? Is this the motivation for the civil litigation reform?

Incidentally, I really enjoyed Dr. Feynman's article on the first shuttle crash. He asked the
engineers on the floor what their estimate of total vehicle loss on any given mission was, approx. 1
in 50 or 1 in 100. He THEN asked NASA management, who confidently assured him the chances were more
like 1 in 100,000. It seems the same problems illustrated 15 years ago reveal themselves again.

Cheers,

Scott..

<jobst.brandt@stanfordalumni.org> wrote in message news:OFq3b.16156$dk4.534441@typhoon.sonic.net...
> Mike Shaw writes:
>
> >> If no one knew about it, what would prompt someone to do something?
>
> > If noone knows, is there a really a problem?
>
> Noon is the time we usually eat lunch, no one should have a problem with that...
>

Well, since Miraim-Webster puts a space in, from now on so will I.

> However, causes for all sorts of common phenomena are being discovered daily. That wheels have
> separated is not a contention here but what one of the causes are is.
>

A small correction of terminology: a potential cause.

> > Seems that someone would know if they had a problem with their dropouts, and the LBS would start
> > to hear about it, and then the manufacturers would start to get warranty claims, and...
>
> Oh, what you say. We read here regularly of people who have common mechanical problems with their
> bicycles and are at a loss to explain what the cause is. Likewise, those who have had a wheel come
> out are no better informed, especially since attributing it to incorrect QR closure is simple and
> entirely believable. For proof of that, just read the insulting responses James Annan has gotten
> from this forum.
>
> > Sounds to me like some little boy's calling "wolf."
>
> Mike, what motivates you to take this position?
Why do you feel so attacked that you must go on the offensive and give rude retorts to someone who
has done nothing to you?
>
Now THAT'S the pot calling the kettle black! At least in this post you're being polite, thank you.
To answer, I don't feel like I'm being attacked, I just feel that there are people out there trying
to create a problem where there really isn't one.

That there are wheels being ejected for some reason is a given. We've got actual examples. To blame
everything BUT user error sounds like someone's crying wolf. If there is a real problem, AND it can
be definitively proven to be the QR/dropout design, I'll be the first to change my opinion. Right
now, I haven't seen anything to definitely PROVE that it's the QR.

Personal experience, the personal experience of everyone I know, and everyone they know (and a lot
work in shops) hasn't come up with one example of this phenomenon in the SoCal/San Diego area that
I've heard of. Have you heard of anyone that has had the problem? Seems to me that if there were
actually a problem, at least one of us would've heard about it by now.

Mike

> Jobst Brandt jobst.brandt@stanfordalumni.org Palo Alto CA

Mike S. said...

> Now THAT'S the pot calling the kettle black! At least in this post you're being polite, thank you.
> To answer, I don't feel like I'm being attacked, I just feel that there are people out there
> trying to create a problem where there really isn't one.
>
> That there are wheels being ejected for some reason is a given. We've got actual examples. To
> blame everything BUT user error sounds like someone's crying wolf. If there is a real problem, AND
> it can be definitively proven to be the QR/dropout design, I'll be the first to change my opinion.
> Right now, I haven't seen anything to definitely PROVE that it's the QR.
>
> Personal experience, the personal experience of everyone I know, and everyone they know (and a lot
> work in shops) hasn't come up with one example of this phenomenon in the SoCal/San Diego area that
> I've heard of. Have you heard of anyone that has had the problem? Seems to me that if there were
> actually a problem, at least one of us would've heard about it by now.
>
> Mike

The only place I have heard about unexplained wheel ejection is in these usenet threads. This isn't
to say that it never happens, it just isn't that common compared to the usual mechanical failures
like bent rims, and broken frames. As off-road bicyclists we just have more important things to
worry about. I was always willing to admit that James Annan had an interesting point, but it was the
hype, the ego and the exaggeration that made me want to jump in and throw some obstacles in front of
the band wagon, for whatever good it did. Less scare-mongering and arrogance might have actually
resulted in a better reception by the world cycling community. Instead we get a guy trying to set
himself up as the Ralph Nader of bicycles. How could any rational person not give a resounding Bronx
cheer to that? Fortunately, the bicycling community is smaller and more sophisticated than the auto
industry and that turkey won't fly in this little world.

Tim McNamara <timmcn@bitstream.net> wrote:

>> The CPSC is supposed to be above politics
>
>The CPSC on which planet? The one in the US is terminally embroiled in politics, and those politics
>change like the wind with the various Administrations. This Administration is determined to remove
>as much government interference from business as possible (while maximizing big government
>interference into people's personal lives). You can be sure that the CPSC will be rendered as
>powerless as possible for the next 6 years.

I get it. It's a conspiracy! The government wants to hide this huge problem with disc brakes and
quick releases, which is a dire threat to the health and freedom of all cyclists, so that Big
Business (the bike industry? Hah) will thrive. But little Timmie McNamara knows the TRUTH. He heard
it from James Annan, who crashed on his tandem, and Jobst Brandt, who knows everything. So it must
be true. Forget the fact that if it were true, it would be in the interest of the CPSC and the
cycling industry to nip it in the bud, BEFORE the tort lawyers blow the whole thing to holy hell.
And that only a tiny minority of cyclists have been injured by this problem, IF it's a problem and
IF the problem caused the injury. --dt

"Mike S." <mikeshaw2@coxDOTnet> writes:

> That there are wheels being ejected for some reason is a given. We've got actual examples. To
> blame everything BUT user error sounds like someone's crying wolf.

"To blame *everything* but user error"? James is putting the blame on precisely one thing. It is
those who do not understand engineering mechanics that are missing the point.

> Personal experience, the personal experience of everyone I know, and everyone they know (and a lot
> work in shops) hasn't come up with one example of this phenomenon in the SoCal/San Diego area that
> I've heard of.

Lots of products have been recalled, how much personal experience do you have with people being
injured as a result of a defective design that was recalled? I cannot think of anyone. Presumably
the CPSC doesn't rely on personal experience when making a judgement. Are recalls unjustified unless
most people have personal experience with that product failure [rhetorical question]?

Joe Riel

"S. Anderson" <scott.anderson3@zsympaticoz.ca> wrote in message
news:T%x3b.2308$O05.562125@news20.bellglobal.com...
> "Jay Beattie" <jbeattie@lindsayhart.com> wrote in message
> news:vkt9m9konbqeca@corp.supernews.com...
> >
> >
> > > Hey, if tort law "reform" passes, even the civil court route might fail. Caveat emptor.
> >
> > Class action and tort reform is needed, and the reform I have seen proposed would not prevent
> > most products-related law suits. It
usually
> > involves damages caps and exclusive federal jurisdiction over
certain
> > suits, and most proposed reform at the local level involves doctors
who
> > have been sued out of delivering babies. It will never pass anyway, because the trial lawyers
> > have more money than industry -- plus they
get
> > Erin Brockovich to display her breasts and talk about the importance
of
> > the jury system -- when her famous case was decided by an arbitrator
(go
> > figure). -- Jay Beattie.
> >
> >
>
> Interesting. I think it's commonly thought up here (Canada) that the
civil
> legal system is out of control in the States. We often read things
about
> auto lawsuits (I'm in the engineering business) and wonder which way
is up.
> You know, the usual millions awarded some drunk driver who fell asleep
at
> the wheel at 140mph and crashed into a bridge abutment whose family
argues
> that the car should have protected the driver against all foreseeable impacts, or someone with a
> "back injury" who sues for salary and the
right
> to never work again due to this injury etc etc. Is that the common
thought
> in the States as well? Is this the motivation for the civil
litigation
> reform?

The too big verdict is one of the motivating factors for tort reform, but the more important problem
is the effect of mass tort litigation on certain legitimate industries, and the abuse of the class
action procedure. Random bad verdicts will always occur, but there are system problems that could be
fixed without denying reasonable compensation to legitimately injured plaintiffs. It has been done
in Canada and elsewhere in the civilized world. -- Jay Beattie.

"Mike S." <mikeshaw2@coxDOTnet> wrote in message news:<dTB3b.30101$cj1.11404@fed1read06>...
> <jobst.brandt@stanfordalumni.org> wrote in message
> news:OFq3b.16156$dk4.534441@typhoon.sonic.net...

> > However, causes for all sorts of common phenomena are being discovered daily. That wheels have
> > separated is not a contention here but what one of the causes are is.
> >
>
> A small correction of terminology: a potential cause.
> >
> > > Sounds to me like some little boy's calling "wolf."
> >
> > Mike, what motivates you to take this position? Why do you feel so attacked that you must go on
> > the offensive and give rude retorts to someone who has done nothing to you?
> >
>
> Now THAT'S the pot calling the kettle black! At least in this post you're being polite, thank you.
> To answer, I don't feel like I'm being attacked, I just feel that there are people out there
> trying to create a problem where there really isn't one.

Or that the problem has not been clearly defined in it's actual failure mode.

> That there are wheels being ejected for some reason is a given. We've got actual examples. To
> blame everything BUT user error sounds like someone's crying wolf. If there is a real problem, AND
> it can be definitively proven to be the QR/dropout design, I'll be the first to change my opinion.
> Right now, I haven't seen anything to definitely PROVE that it's the QR.

That's not entirely accurate. At this point, it is really unknown what the "user error" failure rate
is, in comparison to the proposed mechanism.

> Personal experience, the personal experience of everyone I know, and everyone they know (and a lot
> work in shops) hasn't come up with one example of this phenomenon in the SoCal/San Diego area that
> I've heard of. Have you heard of anyone that has had the problem? Seems to me that if there were
> actually a problem, at least one of us would've heard about it by now.

Mr. Annan seems to think his anecdotes are golden, while everyone else's anecdotes are a little more
"brown", if you get my meaning.

Ms. Macnamara (sorry about the spelling if it is not correct) Mr. Brandt and Mr Annan, plus some few
others, consider this hypothesis as reality, and that it's fixed in stone that "this is what
happens." But they seem to blanch at responding to these questions:

What is the ratio of user error failures to Annan Hypothesis failures?

What is the effect of knurling on the QR and hub nut faces? (The unscrewing mechanism is an analogy
to vibrational loosening which is well-documented, EXCEPT - when was the last time you saw a screw
with a knurled mating face? A bolt? A nut? A washer, other than lockwashers, which are "knurled" for
a reason!) As the unscrewing mechanism applies to *this particular application*, under what
conditions does it happen with the QR done up *as the manufacturer recommends*? How about when it's
tighter than that?

How was the 0.6g decelleration figure arrived at? (This is one I've had a problem with from the
beginning - I don't know where to get a g-meter for my mtb. I would be willing to experiment if
I had one.)

Why is only the rotor side considered in the calculation? The fork ends are not free-floating,
frictionless, independent entities.

I have seen a bunch of hand waving at these questions, like they don't matter. And I have seen
condescending remarks thrown around about "look it up." And yet, when I go and "look it up," I
see nothing but more hand-waving! Mr. Brandt's claim of the existance of statistics. That one was
a laugher.

The fact is, I want to know specifics, and not hear "any mechanical engineer would know that this
is" thus and such. OK, I'm not one. Convince me that this a real threat, and not a potential threat.
There are real threats out there - like every time I drive an automobile, there is a real and
quantifiable threat of injury and death. Likewise just about every other activity. And there are
things that I can do to mitigate the potential threats.

Here are the things I see:

Downward force on the drop-out - bad. Moving the disk mounts to the other side, and in front of the
fork would solve that problem with no changes to the rest of the system.

Potential unscrewing of the QR - bad. Without this part of the equation, the downward force is
merely a result of design compromise. This is the area that I see needs to be elucidated more - what
is the threshold tension, what effect does knurling have, how do those two things interact, etc.

Actual force on the dropout from braking - number of unknown value. .6g is pretty high for a mtb on
dirt. I'm not sure how often I get to 0.6g on pavement, let alone dirt. Knobbies are not well-suited
to pavement, so it's hard to judge. From my time spent running around a track in my car, I rarely
see 0.6g on the street (driving in a regular fashion.) On the track, quite often, and by estimate of
what my body feels when I'm on dirt, 0.6g doesn't happen a lot. If at all. I need a g-meter to test
this. This is the one number that I feel has been "pulled out of the air."

I wouldn't have any problem with the discussion at all - except that the aforementioned proponents
of the Annan Hypothesis seem to think that dimissive condescension makes these questions up and
disappear. They do not. In fact, the handwaving strengthen these questions, and make me wonder what
the real motivation is. If they'd drop the pretense of "knowing", and approach it more as "answering
the questions posed in a straight-forward manner", then I might be more inclined to spend my time
writing to, oh, the CPSC! Or Marzocchi. As it is, I am sitting with figurative arms crossed, waiting
for more definitive answers, including the German experiments mentioned previously.

Robert F. Jones (Spider, to the rest of USENET)

Mike Shaw writes:

>> Mike, what motivates you to take this position? Why do you feel so attacked that you must go on
>> the offensive and give rude retorts to someone who has done nothing to you?

> Now THAT'S the pot calling the kettle black! At least in this post you're being polite, thank you.
> To answer, I don't feel like I'm being attacked, I just feel that there are people out there
> trying to create a problem where there really isn't one.

> That there are wheels being ejected for some reason is a given. We've got actual examples. To
> blame everything BUT user error sounds like someone's crying wolf. If there is a real problem, AND
> it can be definitively proven to be the QR/dropout design, I'll be the first to change my opinion.
> Right now, I haven't seen anything to definitely PROVE that it's the QR.

> Personal experience, the personal experience of everyone I know, and everyone they know (and a lot
> work in shops) hasn't come up with one example of this phenomenon in the SoCal/San Diego area that
> I've heard of. Have you heard of anyone that has had the problem? Seems to me that if there were
> actually a problem, at least one of us would've heard about it by now.

OK. How about a simple experiment, assuming you have access to a disk brake equipped bicycle. Since
retention ridges are only on the outside of the fork dropout, remove the QR skewer and perform a
static braking test by pushing the bicycle forward with the brake applied. You could also do this at
low speed without hazard. Then report whether this disengages the wheel or not.

This is intended to demonstrate that there is a separating force, something that has been argued
here at length.

Jobst Brandt jobst.brandt@stanfordalumni.org Palo Alto CA

<jobst.brandt@stanfordalumni.org> wrote in message news:MhL3b.16451$dk4.541184@typhoon.sonic.net...
> Mike Shaw writes:
>
> >> Mike, what motivates you to take this position? Why do you feel so attacked that you must go on
> >> the offensive and give rude retorts to someone who has done nothing to you?
>
> > Now THAT'S the pot calling the kettle black! At least in this post you're being polite, thank
> > you. To answer, I don't feel like I'm being attacked, I just feel that there are people out
> > there trying to create a problem where there really isn't one.
>
> > That there are wheels being ejected for some reason is a given. We've got actual examples. To
> > blame everything BUT user error sounds like someone's crying wolf. If there is a real problem,
> > AND it can be definitively proven to be the QR/dropout design, I'll be the first to change my
> > opinion. Right now, I haven't seen anything to definitely PROVE that it's the QR.
>
> > Personal experience, the personal experience of everyone I know, and everyone they know (and a
> > lot work in shops) hasn't come up with one example of this phenomenon in the SoCal/San Diego
> > area that I've heard of. Have you heard of anyone that has had the problem? Seems to me that if
> > there were actually a problem, at least one of us would've heard about it by now.
>
> OK. How about a simple experiment, assuming you have access to a disk brake equipped bicycle.
> Since retention ridges are only on the outside of the fork dropout, remove the QR skewer and
> perform a static braking test by pushing the bicycle forward with the brake applied. You could
> also do this at low speed without hazard. Then report whether this disengages the wheel or not.
>
> This is intended to demonstrate that there is a separating force, something that has been argued
> here at length.

Yeah, and I'll bet that if you did the same with cantis or V-brakes, it'd do the same thing. Since I
haven't tried it, I don't know. Anyone willing to try?

I've got an F3000 out in the garage that I can experiment with in a bit. I'll let you know
what happens.

Mike

>
> Jobst Brandt jobst.brandt@stanfordalumni.org Palo Alto CA