Missy Giove's QR pops open



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In news:[email protected], James Annan <[email protected]> typed:
>
> As an attorney, you will have noted the comments from Russ Rose (Rockshox/SRAM) and Trek's lawyer,
> indicating their experience in dealing with claims due to wheel loss. As an attorney, I bet if
> someone had come to you asking for representation in such a case 2 months ago, you would have told
> them there was no point in pursuing the matter as it was well established that the QR was
> infallible. I doubt you would tell them that today.
>
> However, of the dozen(ish) wheel loss incidents I have heard about (about half of which resulted
> in hospital trips), I don't think a single one has even been reported to the fork manufacturer
> (except, of course, the one where the fork manufacturer himself lost his own front wheel). I don't
> really know to what extent these dozen incidents might represent merely the tip of the iceberg.
> It's not surprising that experienced cyclists didn't realise the fork was at fault. I think that
> will change soon and I would expect claims for compensation to be made on a regular basis from now
> on, including perhaps some backdated ones. When claims are made, I'd certainly expect many to win.
> In fact I'd bet my house on
> it. How lucky are _you_ feeling today?
>

Perhaps another way to put this in perspective. The sorts of accidents you are postulating will tend
to be high speed aggressive braking probably on a steep downhill. Such accidents will tend to be
serious - wheel loss leading to sudden pitch forward onto fork ends and head into ground. Yet I
believe Russ has the dubious honour of being only the first or second mountain biker in Stoke
Mandeville which is where all serious spinal injuries in the UK tend to be transferred for
specialist treatment. If there is a big iceberg there the tip is mighty small.

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer
 
In news:[email protected], Tim McNamara <[email protected]> typed:
>
> One possible objection is that the dropout you propose would be shaped like an old road horizontal
> dropout, with the caliper force pushing against the lower "jaw" of the dropout and possibly
> breaking it off after a few cycles (especially if it's aluminum). That would simply recreate the
> results of ejecting the axle from the standard dropout.
>

Hell if its going to break from the pressure of the braking ejection force the back of a current
dropout would surely have sheared off years ago from the heavy battering it gets from the wheel
running into rocks, kerbs etc.

>> It also avoids all the problems of putting the mounting tabs under tension, where they are much
>> weaker, instead of compression.
>
> I'd have to leave this to the engineers, but in this case I don't think there'd be a difference.
> Seems to me that if there are two mounting points- an upper and a lower- one would be loaded in
> tension and the other in compression regardless of whether the caliper is in front or behind.

As has been discussed elsewhere by the engineers there are some serious problems to mounting the
caliper on the front and putting the mounts under tension.

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer
 
In news:[email protected], James Annan <[email protected]> typed:
>
> Because that still leaves the loosening aspect of the problem much the same as before. The axle
> doesn't need a long slot to slide up and down in order to loosen, there is enough slack across the
> dropout slot (as shown by the numerous reports of rear wheel loosening). Of course changing the
> slot angle will reduce the likelihood of the wheel being forcibly ejected, but it will still
> require unreasonable skewer tension to hold in place.
>

Well if its going to loosen through the existence of disk brakes anyway I'd far rather have the exit
path in the one direction other forces are not severe than downwards or backwards. There are very
few circumstances that would push a front wheel forward out of a dropout but, if it is loose, plenty
that would push it downwards including gravity when jumping/lifting the front wheel.

It seems though that you are now arguing that any caliper configuration will lead to the QR
loosening so are you advocating QRs should not be used with disc brake period? Because if you are we
can all forget repositioning the caliper as every disc brake will need a bolt through axle.

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer
 
Mark Hickey <[email protected]> wrote:

>I have to believe Doug has never ridden a non-disc brake bike that's set up very well. Sure, disc
>brakes work well, but so do cantis if they're set up well. The question is whether any incremental
>improvement you get with disc brakes is worth the extra weight, expense and potential drag. For an
>awful lot of riders out there, the answer is "no".

Don't forget wet conditions and ice. I live in the northeast.

I liked the endorsement in Velonews about 2 or 3 issues back, wherein it was reported that Shimano
is "requiring" all World Cup x-c racers who get comped with XTR to use the discs as well, and
Velonews predicted that once the elite actually started using them, albeit by force, they would
never go back. I obviously concur.

It boggles my mind how anyone can seriously argue that any rim brake is equal or superior to discs,
unless it is the case that the proponent simply has not used them extensively. There is really not
much argument.

Sorry, cantis are for retrogrouches with old bike frames, and V-s for riders who don't care about
modulation and are concerned about the weight "penalty" (as a footnote, why is it that retrogrouches
in all other respects pooh-pooh gram counting but not when it comes to discs?)

All I can say that whenever I switch from my disc equipped dualie to my fully rigid SS with V-s, the
difference in the brakes is at least as noticeable, if not more so, than the lack of front and rear
suspension. The lack of gearing is last on the list.

--dt
 
In news:[email protected], Tim McNamara <[email protected]> typed:
>
> James Annan, Jobst Brandt and Chris Juden- to name three- are not "clueless and inexperienced
> morons."

Jobst AFAIK doesn't ride mountain bikes, Chris does but I've found some of his comments in the CTC
magazine "curious", James I don't know about.

> When it's muddy, I don't ride on the trails because it's destructive and leads to trail erosion
> and closures. Riding in the mud may be fun, but it's selfish.
>

If I followed that advice I would rarely get out off-road ;-(

> Disk brakes *do* exert an ejection force on the axle because the design necessarily makes it so.
> Simple as that. If you want to experiment, turn your bike upside down, loosen the QR, spin your
> wheel in the appropriate direction, and hit the brake. The axle will pop out of the dropout either
> partially or completely. That *is* the design flaw and it's not a hypothesis, unless you think
> that Newtonian laws of physics and pi are also hypotheses.
>

I guess you could say, take out all the wheel bolts on a car and drive down the road. The wheels
fall off. Is that a design flaw? No because the wheel bolts prevent them from falling off. It is not
uncommon that things would come apart in use without the fasteners. So whether its a design flaw or
not depends on the design of the fastening system.

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer
 
On 05 Jun 2003 15:25:17 +0100 (BST), David Damerell <[email protected]> wrote:
>Jasper Janssen <[email protected]> wrote:
>><[email protected]> wrote:

>>>Otherwise you might have to explain exactly _how_ James is going to make money off the "scam",
>>>hmm? And that might be a little tricky.
>>Two words: expert witness.
>
>You might be able to accuse Jobst of that, but James does not have the prior experience that would
>let him effectively exploit such a possibility.

I don't intend to accuse anyone, but it is the only way I can possibly see for either of them to
make any money from the whole debacle.

Jasper
 
On Wed, 4 Jun 2003 18:32:22 +0100, "Tony Raven" <[email protected]> wrote:

>There are very few circumstances that would push a front wheel forward out of a dropout

How about braking on the rear wheel?

Jasper
 
Jasper Janssen wrote:

>
> I don't intend to accuse anyone, but it is the only way I can
possibly see
> for either of them to make any money from the whole debacle.

So in that case it is clear that I'm not going to make any money from it, despite your and
superslinky's mud slinging.

James
 
Tony Raven wrote:

>
> It seems though that you are now arguing that any caliper configuration will lead to the QR
> loosening so are you advocating QRs should not be used with disc brake period? Because if you are
> we can all forget repositioning the caliper as every disc brake will need a bolt through axle.

I don't know for sure. As you said earlier, a poor 'solution' that does not address the problem
properly, may be worse than no solution at all. If skewers have to still be over-tight to prevent
unscrewing then that is not IMO a satisfactory solution. But I'm not trying to say what must be
done, rather pointing out some possible flaws in attempted solutions.

If any sort of full axle clamp is considered unreasonable, then a changed dropout angle combined
with a properly threadlocked skewer seems like it should be fine. However changing skewer design may
be a slow process as their manufacturers have no real need to change, roadies don't need it and
might object, but two forms of skewer on the market would be a recipe for disaster etc...

However a fully-surrounded clamped axle need not be that complex, Jobst's idea of a conical
interface might be fine, and there are already designs for end clamps from the bolt-through market
that could easily be adapted to clamp on teh stubs of a standard axle. I've seen some that just flip
off by hand, wheel removal would not be tedious and if lawyer lips were simultaneously dropped, it
might even be better than the current arrangement.

James
 
Tony Raven wrote:

> Perhaps another way to put this in perspective. The sorts of accidents you are postulating will
> tend to be high speed aggressive braking probably on a steep downhill. Such accidents will tend to
> be serious - wheel loss leading to sudden pitch forward onto fork ends and head into ground. Yet I
> believe Russ has the dubious honour of being only the first or second mountain biker in Stoke
> Mandeville which is where all serious spinal injuries in the UK tend to be transferred for
> specialist treatment. If there is a big iceberg there the tip is mighty small.

I agree with that, most of the injuries are facial and head, a few concussions but (apart from Russ)
I know of no long term serious harm. You might have seen there was a narrow escape mentioned on STW
last year where someone was in intensive care (coma?) for a couple of days, but AFAIK they recovered
fine. I really don't know how these figures might translate to world-wide numbers. It does seem
quite possible that the UK is particularly susceptible, due to (any combination of) early adoption
of disks, a fashion for feeble skewers, and a habit of going on long day rides with lengthy descents
rather than round purpose-built courses for an hour or two at a time.

James
 
Tony Raven wrote:
> In news:[email protected], Tim McNamara <[email protected]> typed:
>
>>James Annan, Jobst Brandt and Chris Juden- to name three- are not "clueless and inexperienced
>>morons."
>
> Jobst AFAIK doesn't ride mountain bikes, Chris does but I've found some of his comments in the CTC
> magazine "curious", James I don't know about.

James and jules were UK Trailquest champions and won the Manx End-to-End (both in the tandem
category only!), raced in the Transrockies Challenge last year (including a stage win and a 2nd
place in the mixed category) but most of our MTBing is just our commute to work these days. We've
also designed several of our bikes, partially built two of the frames and assembled and
maintained the rest.

James
 
In article <[email protected]>, Jasper Janssen <[email protected]> wrote:

> On 05 Jun 2003 15:25:17 +0100 (BST), David Damerell <[email protected]> wrote:
> >Jasper Janssen <[email protected]> wrote:
> >><[email protected]> wrote:
>
> >>>Otherwise you might have to explain exactly _how_ James is going to make money off the "scam",
> >>>hmm? And that might be a little tricky.
> >
> >>Two words: expert witness.
> >
> >You might be able to accuse Jobst of that, but James does not have the prior experience that
> >would let him effectively exploit such a possibility.
>
> I don't intend to accuse anyone, but it is the only way I can possibly see for either of them to
> make any money from the whole debacle.

And is there some reason to assume this is their motivation? Or is this just a continuation of the
ad hominem that has become part and parcel of this discussion?
 
Mark Hickey said...

> I have to believe Doug has never ridden a non-disc brake bike that's set up very well. Sure, disc
> brakes work well, but so do cantis if they're set up well. The question is whether any incremental
> improvement you get with disc brakes is worth the extra weight, expense and potential drag. For an
> awful lot of riders out there, the answer is "no".

The main thing I like about discs is that they are easier to set up, at least for me. I was
constantly fiddling with my V's. Not to mention the fact that they wore grooves in the rim and the
pads didn't last. If I keep my old full rigid, I'm going to put a suspension fork on it with discs.
V's are OK for the rear. My discs don't rub at all now that I got them dialed in. I think the much
better modulation I get with discs makes them worth it.
 
Tim McNamara <[email protected]> wrote in message
news:[email protected]...

<snip>

> Modern bicycle disk brakes are a real improvement in one situation only: mud.

What total, utter and complete 'codswallop' (as my gran would have said). Modern hydraulic disk
brakes (not talking about the nasty stuff here) out-perform modern cable rim brakes (again,
referring to good quality pieces of engineering) in every desirable way _period_.

I live in the UK, have ridden in wet, dry, clean and muddy using both rim brakes (centre pull and
side pull road callipers, MTB canti's, MTB V's) and hydraulic disc (Hope Mini) at different times.
The hydraulic disk out-performs any of the rim brakes in any and all conditions.

Overall stopping power is greater and requires less physical effort, controlling the delivery of
that stopping power is easier than with (especially) the V's - there's just no question about their
superior performance.

Wake up and smell the bacon.

Shaun aRe
 
Shaun Rimmer <[email protected]> wrote:
>Tim McNamara <[email protected]> wrote in message
>>Modern bicycle disk brakes are a real improvement in one situation only: mud.
>Overall stopping power is greater

How _exactly_ can you have more stopping power than enough to lift the back wheel?

>and requires less physical effort,

Yes, hauling away on brake levers is pretty hard work - not like that pedalling stuff, that
anyone can do.
--
David Damerell <[email protected]> flcl?
 
"David Damerell" <[email protected]> wrote in message
news:xUw*[email protected]...
>
> How _exactly_ can you have more stopping power than enough to lift the back wheel?
>

Modulation. V-brakes are too grabby so you can't go confidently as close to the limit as you can
with discs. Personally I think the hydraulics are the key factor though as in the dry my Magura rim
brakes are everybit as good as my Hope discs

>
> Yes, hauling away on brake levers is pretty hard work - not like that pedalling stuff, that
> anyone can do.
> --

You have clearly never ridden a long technical downhill on a bike or you would not be saying that

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer
 
"Gary Young" <[email protected]> wrote in message
news:[email protected]...
> "Doug Taylor" <[email protected]> wrote:
>
> <snip>
> > The good news is that to date catastrophic results from the
hypothesized
> > flaw are statistically miniscule. It happens very infrequently
given the
> > vast number of disc equiped mountain bikes in use, and the legions
of yahoos
> > as well as experienced folk who ride them. If this were NOT the
case,
> > trust me, as an attorney, the lawsuits would have commenced in
floods by
> > now, and they have not.
> <snip>
>
> I've seen this hypothesis -- that the absence of lawsuits means a product is safe -- many times on
> this list (most recently in a current thread on fork crown design). I don't think it's true.
> Lawyers who sue manufacturers often have to make a significant initial investment that they may
> not see repaid for years. Yes, there has been an explosion of litigation, but no, attorneys do not
> sue everyone in sight, at least as far as I can tell as a legal reporter. They look for deep
> pockets, big damages (or if damages are small, they look for cases that can be brought as class
> actions), and quick turnarounds.

Depends. Products cases are a lot easier to prove than you think, and the initial investment is
rarely more than having a local expert do a review. You come up with a theory, combine it with bad
injuries and then get a settlement -- unless there is a glaring problem with the case, like the
plaintiff jumped the bike out of a helicopter or off a cliff, or took a file to a fork blade. These
cases come and go all the time, and many never result in suit -- and fall well below the radar of a
legal reporter. For example, I had a spate of bad fork cases ten years ago, but all of those
settled. The public learned of these cases through a recall, and not because of any reported law
suits. The cases were brought by strip-mall lawyers who invested minimal time and effort into the
cases and got a reasonable pay-off. One case approached six figures, but that involved a major
facial re-arrangement and a week in the hospital and a claimed closed-head injury. Interestingly,
none of the experts hired by the plaintiffs in these cases picked up on the real defect, which was a
very subtle manufacturing process error which was quickly cured.

<snip>

> My conclusion -- it just isn't true that greedy lawyers have looked into every possibility. Just
> like the rest of us, they often operate on a kind of herd mentality -- seeing what has worked for
> other attorneys, getting the pleadings, and plugging in their client's names. Developing a new
> cause of action, or even an understanding of an unfamiliar industry, requires a considerable
> investment of time and money.

Lawsuits are injury driven. If some defective part breaks a million time but causes no injury, all
you will see are warranty claims, but probably no lawsuits. If a part breaks once and causes an
injury, you will see a claim and perhaps a lawsuit. There also may be a CPSC incident report, and if
the problem is pervasive, a recall. In any case, the manufacturers I have worked for will fix a real
problem ASAP.

Where there a many injuries, you will see sharing among the attorneys and the inevitable
case-in-a-box sale and referral network. You can get an entire smoker's suit against Philip Morris
on CD for a few bucks, or maybe even free now (including exhibits, deposition and trial transcripts
and examination outlines). Indeed, the re-sale value of cases has prompted various trial lawyers'
associations (ATLA, among others) to sponsor legislation prohibiting confidential settlements and
protective orders prohibiting the dissemination of documents obtained from defendants. They want to
preserve the re-sale value of their cases -- its like getting stud fees from a winning horse. This
probably would never happen in the bicycle world since there are not that many product-related
accidents and the injuries are rarely very big. -- Jay Beattie.
 
Tony Raven <[email protected]> wrote:
>"David Damerell" <[email protected]> wrote in message
>>How _exactly_ can you have more stopping power than enough to lift the back wheel?
>Modulation. V-brakes are too grabby so you can't go confidently as close to the limit as you can
>with discs.

This seems to come down to "V-brakes are too grabby", not that discs are a great improvement over
previous non-grabby brake technologies. You can be that confident with cantilevers; discs can't have
more stopping power than that.

>>Yes, hauling away on brake levers is pretty hard work - not like that pedalling stuff, that
>>anyone can do.
>You have clearly never ridden a long technical downhill on a bike or you would not be saying that

Sure I haven't. Or maybe I have? Who knows? It's still got to be a damn sight less work for the
fingers to work the brakes than for the legs to push you _up_ the hill in the first place.
--
David Damerell <[email protected]> flcl?
 
In article <[email protected]>, "Shaun Rimmer" <[email protected]> wrote:

> Tim McNamara <[email protected]> wrote in message
> news:[email protected]...
>
> <snip>
>
> > Modern bicycle disk brakes are a real improvement in one situation only: mud.
>
> What total, utter and complete 'codswallop' (as my gran would have said). Modern hydraulic disk
> brakes (not talking about the nasty stuff here) out-perform modern cable rim brakes (again,
> referring to good quality pieces of engineering) in every desirable way _period_.

In what way do they perform better?

> I live in the UK, have ridden in wet, dry, clean and muddy using both rim brakes (centre pull and
> side pull road callipers, MTB canti's, MTB V's) and hydraulic disc (Hope Mini) at different times.
> The hydraulic disk out-performs any of the rim brakes in any and all conditions.

In what way do they outperform?

> Overall stopping power is greater and requires less physical effort, controlling the delivery of
> that stopping power is easier than with (especially) the V's - there's just no question about
> their superior performance.

Utter tripe (the US version of codswallop, perhaps). Your stopping power is limited by traction and
has nothing to do with what type of brakes you're using, as long as the brake can lock up the wheel.

> Wake up and smell the bacon.

Wake up and stop hallucinating. Or go back to the Dwarf.
 
In news:eek:[email protected], Jasper Janssen <[email protected]> typed:
> On Wed, 4 Jun 2003 18:32:22 +0100, "Tony Raven" <[email protected]> wrote:
>
>> There are very few circumstances that would push a front wheel forward out of a dropout
>
> How about braking on the rear wheel?
>

The ejection forces in such circumstances are less than you would get from gravity if you lifted the
front of your vertical dropout bike. If you are that concerned about the ability of your QR to
retain your wheel under those conditions stop riding now!

Tony

--
http://www.raven-family.com

"All truth goes through three steps: First, it is ridiculed. Second, it is violently opposed.
Finally, it is accepted as self-evident." Arthur Schopenhauer
 
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