Wheel testing....?
harg...@yahoo.com
lightweight wheels to show what their strength is...? To date all the
focus on lightweight and aerodynamics..?
Ryan Cousineau
<4460be97-114a-4805...@g4g2000pri.googlegroups.com>,
"harg...@yahoo.com" <harg...@yahoo.com> wrote:
Yes.
Among other things, the UCI has a fairly ridiculous "burst test" that
requires that low-spoke-count and non-traditional-spoke (aerospoke et
al) wheels not blow apart and leave shrapnel outside the rim when they
fail. If I seem vague, it's because I don't care to check.
That test famously forces the wheel to destruction no matter how
inherently strong it is, though.
As for other wheels, aside from occasional rigorous testing in one
anorak-y bike mag or another (the Germans are particular standouts at
equipment testing that actually tests equipment), what is it you want to
know?
At the risk of being an obvious bore, a strong rim and a reasonable
number of spokes will make a strong wheel. More spokes allow a little
more durability (among other things, breaking one spoke doesn't have to
mean the end of a ride), but most lightweight wheels or aero wheels are
happily compromised away from strength. Some of the goofier ones have
weight limits, and one may take that as a warning.
If you're looking for strong, the parameters are well-known. You could
do worse than ask "What would Chalo do?" since he breaks everything.
If for some reason you're looking for unusually strong wheels that are
really racy, Zipp makes heavy-duty versions of their more popular
wheels. The weight difference is very small.
Some exotic wheels have ended up with a well-deserved reputation for
badness. Notably, the Spinergy four-spoke "death wheel" designs were
hounded from the market in a cloud of warranty claims and
recriminations, and now Mavic appears, with the incredibly stupid R-SYS
design, to have found a whole new way to screw up the bicycle wheel.
They're surely not the only examples.
--
Ryan Cousineau rcou...@gmail.com http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."
harg...@yahoo.com
> In article
> <4460be97-114a-4805-98df-fc5e3d0b6...@g4g2000pri.googlegroups.com>,
>
> "hargo...@yahoo.com" <hargo...@yahoo.com> wrote:
> > I was wondering if anyone knows if there has been any testing of the
> > lightweight wheels to show what their strength is...? To date all the
> > focus on lightweight and aerodynamics..?
>
> Yes.
>
standards for all frames and components. This would allow them to
eliminate the min weight rules.
> Among other things, the UCI has a fairly ridiculous "burst test" that
> requires that low-spoke-count and non-traditional-spoke (aerospoke et
> al) wheels not blow apart and leave shrapnel outside the rim when they
> fail. If I seem vague, it's because I don't care to check.
>
> That test famously forces the wheel to destruction no matter how
> inherently strong it is, though.
>
> As for other wheels, aside from occasional rigorous testing in one
> anorak-y bike mag or another (the Germans are particular standouts at
> equipment testing that actually tests equipment), what is it you want to
> know?
>
> At the risk of being an obvious bore, a strong rim and a reasonable
> number of spokes will make a strong wheel. More spokes allow a little
> more durability (among other things, breaking one spoke doesn't have to
> mean the end of a ride), but most lightweight wheels or aero wheels are
> happily compromised away from strength. Some of the goofier ones have
> weight limits, and one may take that as a warning.
I just think there is a lot of unknowns in wheel design. Since the
consumer is paying so much for wheels I think he should have a more
definitive way of gauging wheel strength. Most wheel companies do not
specify what the intended use of the wheel is with the exception of
aero wheels.
>
> If you're looking for strong, the parameters are well-known. You could
> do worse than ask "What would Chalo do?" since he breaks everything.
>
> If for some reason you're looking for unusually strong wheels that are
> really racy, Zipp makes heavy-duty versions of their more popular
> wheels. The weight difference is very small.
>
> Some exotic wheels have ended up with a well-deserved reputation for
> badness. Notably, the Spinergy four-spoke "death wheel" designs were
> hounded from the market in a cloud of warranty claims and
> recriminations, and now Mavic appears, with the incredibly stupid R-SYS
> design, to have found a whole new way to screw up the bicycle wheel.
> They're surely not the only examples.
>
> --
> Ryan Cousineau rcous...@gmail.comhttp://www.wiredcola.com/
A. Dumas
> If for some reason you're looking for unusually strong wheels that are
> really racy, Zipp makes heavy-duty versions of their more popular
> wheels. The weight difference is very small.
Look for the "404 CX."
cur...@the-md-russells.org
We used to have Jan in 'spring training' and 'spring races', but since
he a) retired or b)was retired (anyone's choice), we've lost the
primary load testing process for wheels and frames.
I don't think we have a current pro that so completely embraces that
role.
Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
cur...@the-md-russells.org
>On Dec 19, 11:09�pm, Ryan Cousineau <rcous...@gmail.com> wrote:
>> In article
>> <4460be97-114a-4805-98df-fc5e3d0b6...@g4g2000pri.googlegroups.com>,
>>
>> �"hargo...@yahoo.com" <hargo...@yahoo.com> wrote:
>> > I was wondering if anyone knows if there has been any testing of the
>> > lightweight wheels to show what their strength is...? To date all the
>> > focus on lightweight and aerodynamics..?
>>
>> Yes.
>>
>Personally I would like to see the UCI implement a set of testing
>standards for all frames and components. This would allow them to
>eliminate the min weight rules.
>
I think that a definitive testing process that would survive what
happens in a court of law when one of the wheels failed would be
prohibitively expensive for small manufacturers. Once someone stamps
'passed' on a set of wheels, they are taking on some liability, so the
testing would have to extensive.
And frames are painted. Its not like lacrosse sticks, where all the
officials have to do is measure the length and catch. So who's to
monitor those that go with light but dangerous frames with some decals
and glaze? Memorize frame silhouettes? Make wheel roll out for Juniors
positively a cakewalk in comparison.
>I just think there is a lot of unknowns in wheel design. Since the
>consumer is paying so much for wheels I think he should have a more
>definitive way of gauging wheel strength. Most wheel companies do not
>specify what the intended use of the wheel is with the exception of
>aero wheels.
>>
Some are 'rider weight' rated, as are many - maybe most - frames
(don't really know as I no longer shop for many frames anymore, but
the last few I bought all had warnings). But those are set way high,
just as a way to make wheels and frames meant for 180 pound and lower
racers available to be sold, knowing that someone over 270 will buy
them anyway. Waiting for one of those 'for 220 pounds or less'
warnings to be tested in a court case...
Ron Ruff
> Personally I would like to see the UCI implement a set of testing
> standards for all frames and components. This would allow them to
> eliminate the min weight rules.
Costly and ineffective. Please don't support this... are we all
toddlers and idiots who must be protected from ourselves? Buy parts
from a reputable company that are not stupid-light and you will be
fine. Companies have a lot incentive to make parts that do not
spontaneously break and kill people... it makes them look bad. If you
want to get those generic 150g made-in-China handlebars for $49 on
ebay, then... it's a free country (or so I wish).
> I just think there is a lot of unknowns in wheel design. Since the
> consumer is paying so much for wheels I think he should have a more
> definitive way of gauging wheel strength. Most wheel companies do not
> specify what the intended use of the wheel is with the exception of
> aero wheels.
Ditto for wheels. The R-Sys have spontaneously self destructed on
numerous occasions, yet they pass UCI testing.
Tom Kunich
news:a8d2d85e-1ec4-47ad...@c34g2000yqn.googlegroups.com...
>
> Costly and ineffective. Please don't support this... are we all
> toddlers and idiots who must be protected from ourselves? Buy parts
> from a reputable company that are not stupid-light and you will be
> fine. Companies have a lot incentive to make parts that do not
> spontaneously break and kill people... it makes them look bad. If you
> want to get those generic 150g made-in-China handlebars for $49 on
> ebay, then... it's a free country (or so I wish).
I'm presently laying here in a lot of pain since my ITM carbon fork
collapsed on a smooth level bike trail at 10 mph knocking he unconscious and
leaving me looking like a freak show with blood bruises all over my face.
Since most of the pieces are missing it is difficult to interpret but it
appears that the left side of the fork broke apart while I was riding
straight level and slow. One of the guys that was with me reported a section
of the fork shooting sideways as if out of a cannon. Hmm, the other side was
unable to carry the load and broke off at the steering fork head.
At the moment I'm not in a good mood concerning ITM.
Jay Beattie
> "Ron Ruff" <rruffrr...@yahoo.com> wrote in message
Sorry to hear that Tom, and I hope you heal quickly. Was there any
prior damage to the fork? Was it old or new? Considering that many of
us are riding on carbon forks, it would be good to know if there is
anyting to learn from your fork failure. -- Jay Beattie.
harg...@yahoo.com
> On Dec 20, 2:24 am, "hargo...@yahoo.com" <hargo...@yahoo.com> wrote:
>
> > Personally I would like to see the UCI implement a set of testing
> > standards for all frames and components. This would allow them to
> > eliminate the min weight rules.
>
The unfortunate fact is that a lot of consumers are ill informed. Even
those of us who are experienced riders have a hard time making a
informed judgment.
AMuzi
Yes:
http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
Tom Kunich
news:25278df8-591d-4bfe...@z4g2000prh.googlegroups.com...
>
> Sorry to hear that Tom, and I hope you heal quickly. Was there any
> prior damage to the fork? Was it old or new? Considering that many of
> us are riding on carbon forks, it would be good to know if there is
> anyting to learn from your fork failure.
The fork wasn't new but it wasn't very old. I think that I installed it only
about 9 months ago replacing an EC50 fork. The ITM fork wasn't damaged in
any way that I could see and it wasn't ridden in any way that should cause
damage to it.
The strange way it broke - shooting a 3 or 4 inch piece sideways off of the
fork - suggests some manufacturing defect.
It also doesn't give me a lot of faith in carbon forks in general.
Unfortunately I don't have any of the pieces that broke save the opposite
side which was holding pretty well. Otherwise I'd be able to see what the
heck happened. And by the time I get back out to that section of trail it
will have been cleaned up.
I have a Strong fork that I've replaced the ITM with. The only problem is
that it is a far shorter steering tube so the bars are way down. I'll see
how that goes.
Tom Kunich
news:hgm0ed$a4h$1...@news.eternal-september.org...
> harg...@yahoo.com wrote:
>> I was wondering if anyone knows if there has been any testing of the
>> lightweight wheels to show what their strength is...? To date all the
>> focus on lightweight and aerodynamics..?
>
>
> Yes:
> http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
I'm getting pretty worried about carbon fiber being used everywhere. Luckily
my injuries aren't serious but they are painful as hell. I'd hate to see
people get serious injuries from exactly the same sort of fall I had when my
fork failed for no reason whatsoever.
Kurgan. presented by Gringioni.
Dumbass -
Given who did the crashing, I vote for "operator error".
thanks,
Kurgan. presented by Gringioni.
Anton Berlin
Try to get the round wheels they seem to roll better than the other
shapes.
Donald Munro
> I'm getting pretty worried about carbon fiber being used everywhere.
> Luckily my injuries aren't serious but they are painful as hell. I'd
> hate to see people get serious injuries from exactly the same sort of
> fall I had when my fork failed for no reason whatsoever.
>
You must be accident prone then, I've been riding carbon bikes with
carbon forks for nigh on 10 years and I've never had anything break on
me, catastrophically or otherwise. Ok the early carbon forks had
aluminium steerers but I've had pure carbon forks for at least the last
5 years. Perhaps you're that whale that, against all probability,
materialized 10000m up in the air.
harg...@yahoo.com
> "AMuzi" <a...@yellowjersey.org> wrote in message
>
> news:hgm0ed$a4h$1...@news.eternal-september.org...
>
> >> I was wondering if anyone knows if there has been any testing of the
> >> lightweight wheels to show what their strength is...? To date all the
> >> focus on lightweight and aerodynamics..?
>
> > Yes:
> >http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
>
safety commisison needs to get involved. Since bike technology is
advancing so quickly the industry needs a association similar to the
SAE (Society of Automotive Engineers). This way they can meet and help
to companies to develop sound manfacturing techniques. Testing
standards would also play a major role. I am very surprised that Mavic
did not do more testing. Campagnolo spends a lot of time testing their
products. There was a picture of Campagnol testing wheels to test the
deflection of a wheel.
Jobst Brandt
>> I'm getting pretty worried about carbon fiber being used everywhere.
>> Luckily my injuries aren't serious but they are painful as hell. I'd
>> hate to see people get serious injuries from exactly the same sort of
>> fall I had when my fork failed for no reason whatsoever.
> You must be accident prone then, I've been riding carbon bikes with
> carbon forks for nigh on 10 years and I've never had anything break
> on me, catastrophically or otherwise. OK the early carbon forks had
> aluminium steerers but I've had pure carbon forks for at least the
> last 5 years. Perhaps you're that whale that, against all
> probability, materialized 10000m up in the air.
You seem to believe the axiom that if you didn't experience it, it
can't happen. Enough carbon fiber fork failures have occurred in this
area to make it an issue. The faithful are quick to reply with your
scenario and to claim the rider had misused the bicycle. Several
pictures of carbon fiber bicycle products that appeared to have
experienced a high explosive attack have been shown on this newsgroup.
Jobst Brandt
Anton Berlin
We just don't believe Kunich because he doesn't actually ride a bike,
thus making it very difficult to break a fork and besides we have yet
to see some photographic proof.
Jobst is a different story, even if you lost all of your european tour
photos from 1962 we know you did it.
Kunich has no such credibility.
PS did you ever find those photos? Great photos IMHO.
thirty-six
If you want strength with light weight, get 12oz sprint rims and lace
them 28 cross three with 15swg, double tied and soldered, fibre
washers, linseed on the threads, no bows, and tension them only so
much that the detensioning spokes upon test loading occur within the
tyre patch. Keep loading the wheel until the tyre bottoms out to
assertain that all loads are accomplished with the correct spoke
tension response. Within the tyre contact all spokes should
detension. Using a 1" rear tyre and a 7/8" front is permissable.
6oz for hub 7oz for spokes/nipples,12oz for rim, 9oz for tyre, total
34oz per wheel. Less than a kilogramme all in. Well built, it would
be difficult to kill such a wheelset. You would certainly hurt
yourself trying. To save the weight of a full water bottle would
seriously reduce the wheelset's reliability.
So go and find some 12oz Super Champion sprint rims and get them built
right. Unless you want for a hillclimb event, lighter weight than
the wheels I suggest is likely to cause problems either in performance
(they fail) or financially (cost per mile).
Bob Schwartz
> On Dec 20, 8:25 am, Ron Ruff <rruffrr...@yahoo.com> wrote:
>> On Dec 20, 2:24 am, "hargo...@yahoo.com" <hargo...@yahoo.com> wrote:
>>
>>> Personally I would like to see the UCI implement a set of testing
>>> standards for all frames and components. This would allow them to
>>> eliminate the min weight rules.
>
> The unfortunate fact is that a lot of consumers are ill informed. Even
> those of us who are experienced riders have a hard time making a
> informed judgment.
As an experienced rider allow me to be the first to call you
a dumbass. Just because lots of people make uninformed
judgments doesn't mean making an informed judgment is hard.
Bob Schwartz
Jay Beattie
> On Dec 20, 12:19 pm, "Tom Kunich" <tkun...@earthlink.net> wrote:> "AMuzi" <a...@yellowjersey.org> wrote in message
>
> >news:hgm0ed$a4h$1...@news.eternal-september.org...
>
> > > hargo...@yahoo.com wrote:
> > >> I was wondering if anyone knows if there has been any testing of the
> > >> lightweight wheels to show what their strength is...? To date all the
> > >> focus on lightweight and aerodynamics..?
>
> > > Yes:
> > >http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
>
> This is a very good reason why the UCI and or the consumer product
> safety commisison needs to get involved. Since bike technology is
> advancing so quickly the industry needs a association similar to the
> SAE (Society of Automotive Engineers). This way they can meet and help
> to companies to develop sound manfacturing techniques. Testing
> standards would also play a major role. I am very surprised that Mavic
> did not do more testing. Campagnolo spends a lot of time testing their
> products. There was a picture of Campagnol testing wheels to test the
> deflection of a wheel.
>
The CPSC is involved, sort of:
16 CFR § 1512.13 Requirements for front fork.
The front fork shall be tested for strength by application of at least
39.5 J (350 in-lb) of energy in accordance with the fork test, §1512.18
(k)(1), without visible evidence of fracture. Sidewalk bicycles need
not meet this requirement.
The regulations also require participation in the creation of
voluntary standards such as the ASTM fork standard (F2274?).
Dangerous products have to be reported and recalled, etc. So even
absent a more rigorous CPSC standard, manufacturers have a strong
incentive to make a durable product to avoid the expense of recalls
and, of course, lawsuits. Based on my experience representing
manufacturers, they do a lot of testing, and they are careful.
Manufacturers are also competing for market share, however, and the
market wants light. As Bontrager put it, "light, strong, cheap, pick
any two." Frames these days weigh less than the cast-crown SP forks I
was riding in '78. Those forks lasted me until 2006 -- when I drove
them in to a garage door opening clamped in to a roof rack. I could
still use them for driving nails or home protection or a boat anchor.
Nobody wants those kinds of forks anymore except for the Grant
Peterson and Surley set, which is a small portion of the market.-- Jay
Beattie.
Tom Kunich
news:4b2ea0e8$0$1652$742e...@news.sonic.net...
>
> You seem to believe the axiom that if you didn't experience it, it
> can't happen. Enough carbon fiber fork failures have occurred in this
> area to make it an issue. The faithful are quick to reply with your
> scenario and to claim the rider had misused the bicycle. Several
> pictures of carbon fiber bicycle products that appeared to have
> experienced a high explosive attack have been shown on this newsgroup.
That is something that concerns me. The people behind me said that three or
four inches of the fork just below the "Y" fitting at the steering junction
shot out sideways as if it had been exploded.
I just got that part off of the bike and looking at it, it peeled off of the
aluminum "Y" spreader perfectly as if it had never been glued on there. But
you can tell from the feel of that area that it had been glued properly. But
how the heck could it have peeled off like that and shot out to one side?
Unfortunately since I was unconscious I never saw the pieces and the other
side that broke off "normally" looked as I expected it to look.
What would you suggest would cause such a failure?
Nate Nagel
> Manufacturers are also competing for market share, however, and the
> market wants light. As Bontrager put it, "light, strong, cheap, pick
> any two." Frames these days weigh less than the cast-crown SP forks I
> was riding in '78. Those forks lasted me until 2006 -- when I drove
> them in to a garage door opening clamped in to a roof rack. I could
> still use them for driving nails or home protection or a boat anchor.
> Nobody wants those kinds of forks anymore except for the Grant
> Peterson and Surley set, which is a small portion of the market.-- Jay
> Beattie.
And yet that "small portion of the market" seems to describe a lot -
maybe even a majority? - of the non-racers whose posts I read here (and
myself, for that matter...)
not disagreeing with you, just making an observation.
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
Anton Berlin
> What would you suggest would cause such a failure?
Kunich, this is all in your imagination and no one believes you until
you post some photos.
It's a very pathetic cry for help and you'll definitely want to pass
this episode along to the psychology team that is treating you.
Peter Rathmann
> "Jobst Brandt" <jbra...@sonic.net> wrote in message
Tom,
Sorry to hear of your accident (here and on the CCC club board) and
also alarmed that the fork would fail so suddenly and without apparent
cause.
Best wishes for a speedy recovery and hope to see you riding again
soon in the East Bay hills.
Peter
z
> "Jobst Brandt" <jbr...@sonic.net> wrote in message
> news:4b2ea0e8$0$1652$742e...@news.sonic.net...
>>
>> You seem to believe the axiom that if you didn't experience it, it
>> can't happen. Enough carbon fiber fork failures have occurred in this
>> area to make it an issue. The faithful are quick to reply with your
>> scenario and to claim the rider had misused the bicycle. Several
>> pictures of carbon fiber bicycle products that appeared to have
>> experienced a high explosive attack have been shown on this newsgroup.
>
> That is something that concerns me. The people behind me said that three
> or four inches of the fork just below the "Y" fitting at the steering
> junction shot out sideways as if it had been exploded.
Did anyone check the grassy knoll for a second shooter?
Tom Kunich
news:a4589be1-7085-443c...@u16g2000pru.googlegroups.com...
>
> Sorry to hear of your accident (here and on the CCC club board) and
> also alarmed that the fork would fail so suddenly and without apparent
> cause.
It's likely that you're going to get into some sort of accident sooner or
later. I'd just as soon get into an accident that was this (relatively)
harmless.
We'll see you on the rides Peter.
Frank Krygowski
>
> Manufacturers are also competing for market share, however, and the
> market wants light. As Bontrager put it, "light, strong, cheap, pick
> any two." Frames these days weigh less than the cast-crown SP forks I
> was riding in '78. Those forks lasted me until 2006 -- when I drove
> them in to a garage door opening clamped in to a roof rack. I could
> still use them for driving nails or home protection or a boat anchor.
> Nobody wants those kinds of forks anymore except for the Grant
> Peterson and Surley set, which is a small portion of the market.
Well, of course you're defining "market" pretty narrowly. There are
plenty of people buying bikes for neighborhood use, for bike path
cruising, for their kids' use, and even a few for utility
transportation. Those people generally don't care a lot about a few
extra ounces.
They'd care even less if it were described as having any potential to
reduce reliability.
- Frank Krygowski
harg...@yahoo.com
getting for his money. I find it absurd to spend so much on a wheel
have so little info.
On Dec 20, 7:49 am, cur...@the-md-russells.org wrote:
> On Sun, 20 Dec 2009 01:24:26 -0800 (PST), "hargo...@yahoo.com"
harg...@yahoo.com
> hargo...@yahoo.com wrote:
> > I was wondering if anyone knows if there has been any testing of the
> > lightweight wheels to show what their strength is...? To date all the
> > focus on lightweight and aerodynamics..?
>
> Yes:http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
>
improvements in terms of durability. Composites is a bit more
reliable, but it is still fragile. Most the advancements are in terms
of fabrication and the types uses such as cranks etc. 3d weave
composites may change all this. But the technology R&D is advancing
slowly. Today it is entering production for very selected applications
(http://www.google.com/url?
sa=t&source=web&ct=res&cd=2&ved=0CBQQFjAB&url=http%3A%2F
%2Fwww.netcomposites.com%2Fnews.asp%3F3874&ei=Y-4uS8q3Mo-
qtgOCjInNBA&usg=AFQjCNHtuzUQhnk_F9wQ67PR1NHW0eRE-
w&sig2=uNgg5PAly1E8FXUm_XabXw).
Ryan Cousineau
"A. Dumas" <alex...@dumas.fr> wrote:
> Ryan Cousineau wrote:
> > If for some reason you're looking for unusually strong wheels that are
> > really racy, Zipp makes heavy-duty versions of their more popular
> > wheels. The weight difference is very small.
>
> Look for the "404 CX."
Yes, and 303 versions. There's also a "MAX" version which is the same
claimed weight as the CX version, leading me to believe it may be two
names for one wheel.
I can afford none of them. It's very sad. Yeah first-world problems!
--
Ryan Cousineau rcou...@gmail.com http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."
Ron Ruff
> The strange way it broke - shooting a 3 or 4 inch piece sideways off of the
> fork - suggests some manufacturing defect.
It doesn't suggest that to me. You were cruising on smooth pavement at
10 mph and the fork exploded. That would suggest to me that a foreign
object was involved...like a stick getting kicked up and caught in the
spokes. If not that, then someone shot your fork.
thirty-six
pellet or BB gun?
Jobst Brandt
> If for some reason you're looking for unusually strong wheels that
> are really racy, Zipp makes heavy-duty versions of their more
> popular wheels. The weight difference is very small.
I don't understand how a broad part of society sees itself as wanting
or needing to own "really racy" equipment but it appears to be
universal, whether the family car, home computer, or bicycle for that
matter. Just look at the huge chromy low profile wheels housewives
use to drive children to school or go shopping. Quad rumble pipes
makes their mount sound more like a Peterbilt with Cummins diesel and
dual stacks than a mundane sedan or station wagon.
Fragile carbon fiber wheels in the multi-thousand dollar range are
just as important to them while fawning over Lance Armstrong's racing
accomplishments. Me too, me too! ... "We won today!" speaking of the
local pro-sport team.
Jobst Brandt
Jobst Brandt
>> The strange way it broke - shooting a 3 or 4 inch piece sideways
>> off of the fork - suggests some manufacturing defect.
> It doesn't suggest that to me. You were cruising on smooth pavement
> at 10 mph and the fork exploded. That would suggest to me that a
> foreign object was involved... like a stick getting kicked up and
> caught in the spokes. If not that, then someone shot your fork.
You're phishing Ron. These carbon bikes are unpredictably fragile as
has been demonstrated by the many failure reports described here on
this newsgroup and seen in pictures.
Jobst Brandt
William Asher
$742e...@news.sonic.net:
Richie Allen, as quoted by Jim Bouton in Ball Four, said "I add 20 points
to my average if I know I look bitching out there." Clearly, Allen is an
idiot and it doesn't matter what you look like, but everyone agrees with
him, so there is a market for really racy wheels.
Everything in life can be reduced to an aphorism involving baseball.
--
Bill Asher
Donald Munro
> Did anyone check the grassy knoll for a second shooter?
It was an IED, or perhaps an IUD.
Tom Kunich
news:4b2f1e23$0$1640$742e...@news.sonic.net...
It is strange isn't it? Why would people buy super expensive ultra-light
wheels that are known to wear out rapidly for riding on their regular rides?
There is hardly any weight difference between the very expensive light
wheels and a good set of training wheels and yet people are not just willing
but anxious to get these small fortunes that are so easy to destroy.
Scott
Many failure reports??? How about this, how about we take a poll of
everyone who has NOT had their fork fail JRA? To say that carbon
fiber forks are unpredictably fragile is such an overstatement. Even
I know the odds are nowhere near 50/50 that they'll fail.
RicodJour
No, he has a point. If it's posted on a newsgroup that affects the
probability of an outcome. I'll show you what I mean.
http://pics.blameitonthevoices.com/032009/hummer_vs_school_bus.jpg
http://www.hummerguy.net/wp-content/2008HummerH3Crash.jpg
See? I've now increased the probability of people having a horrific
Hummer crash (how come I feel like I'm setting up a Munro post...?).
R
Donald Munro
> See? I've now increased the probability of people having a horrific
> Hummer crash (how come I feel like I'm setting up a Munro post...?).
An Asher post. He'll advise you to get a blonde hummer.
andre...@aol.com
> Jobst Brandt <jbra...@sonic.net> wrote in news:4b2f1e23$0$1640
> $742ec...@news.sonic.net:
All true! I was riding with a friend that had gotten a new Carrera
with Campy 11 and Boron wheels. It had fancy, curved carbon tubing and
weighed around 14 pounds. I was riding my allez steel which weighs
about 22 pounds naked, but usually with with two bottles and a seat
pack it weighs over 28 pounds. I told him that with his fancy super
expensive bike, he wasn't riding any faster than me. He responded,
"...but I look good, Andres".
Frank Krygowski
> everyone who has NOT had their fork fail JRA? To say that carbon
> fiber forks are unpredictably fragile is such an overstatement. Even
> I know the odds are nowhere near 50/50 that they'll fail.
I wonder which odds are greater: that the forks will fail, or that the
forks will produce any significant benefit?
Personally, I think the odds are very low in both cases. But the
negative consequences of any failure are more pronounced than the
positive consequences of any benefit.
- Frank Krygowski
andre...@aol.com
Isn't looking good a significant benefit?
Scott
Define "significant benefit".
(disclaimer: I like steel bikes, even steel forks, too)
RicodJour
Would that be a straight line correlation, or is there a speed-
dependent curve? Wouldn't making gene pool selections based on
reaction speed be a benefit to the population as a whole? Of course.
So, in the interests of bettering the species...
Buy Carbon!
Whether it's Heaven or Hell, you'll get there a lot faster!®
R®
Brad Anders
> You're phishing Ron. These carbon bikes are unpredictably fragile as
> has been demonstrated by the many failure reports described here on
> this newsgroup and seen in pictures.
Some older carbon components seem to have been quite durable. I just
replaced the Look carbon fork (from 1994) on my road bike with a new
threadless carbon fork. The old Look fork had been through many
thousands of miles of riding, and several minor accidents, without any
failures or externally obvious flaws. But more to the point, that Look
fork had survived a Jobst Sunday Ride (tm), a clear test of
durability, involving several stream crossings, dirt roads, and irate
road owners yelling at us.
BTW, the visit to that guy's place who had a private railway on his
property still stick in my mind.
Brad Anders
bfd
> Ryan Cousineau wrote:
> > If for some reason you're looking for unusually strong wheels that
> > are really racy, Zipp makes heavy-duty versions of their more
> > popular wheels. The weight difference is very small.
>
> I don't understand how a broad part of society sees itself as wanting
> or needing to own "really racy" equipment but it appears to be
> universal, whether the family car, home computer, or bicycle for that
> matter. Just look at the huge chromy low profile wheels housewives
> use to drive children to school or go shopping. Quad rumble pipes
> makes their mount sound more like a Peterbilt with Cummins diesel and
> dual stacks than a mundane sedan or station wagon.
>
Monday!"
> Fragile carbon fiber wheels in the multi-thousand dollar range are
> just as important to them while fawning over Lance Armstrong's racing
> accomplishments. Me too, me too! ... "We won today!" speaking of the
> local pro-sport team.
>
Anedotal and conjecture. We need PROOF!
Tom Kunich
news:5d488f39-e32b-4c5d...@y10g2000prg.googlegroups.com...
>
> Some older carbon components seem to have been quite durable. I just
> replaced the Look carbon fork (from 1994) on my road bike with a new
> threadless carbon fork. The old Look fork had been through many
> thousands of miles of riding, and several minor accidents, without any
> failures or externally obvious flaws. But more to the point, that Look
> fork had survived a Jobst Sunday Ride (tm), a clear test of
> durability, involving several stream crossings, dirt roads, and irate
> road owners yelling at us.
I trusted my newer forks BECAUSE the older forks turned out to be so
reliable and strong. I'm quite shocked that they failed as they did. Now
I've had two "light, carbon" forks fail on me and I'm in the running for
switching everything back over to steel.
Tom Kunich
news:19117cb9-b7cd-4bd1...@v30g2000yqm.googlegroups.com...
>
> All true! I was riding with a friend that had gotten a new Carrera
> with Campy 11 and Boron wheels. It had fancy, curved carbon tubing and
> weighed around 14 pounds. I was riding my allez steel which weighs
> about 22 pounds naked, but usually with with two bottles and a seat
> pack it weighs over 28 pounds. I told him that with his fancy super
> expensive bike, he wasn't riding any faster than me. He responded,
> "...but I look good, Andres".
This is starting to become shocking. Why would anyone spend a great deal of
money for no apparent reason other than to look like they've spent a great
deal of money?
Ron Ruff
> has been demonstrated by the many failure reports described here on
> this newsgroup and seen in pictures.
Carbon forks have been ubiquitous on pretty cheap bikes for many years
now, and and there is no plague of JRA failures that I'm aware of.
They will shatter quite nicely if you exceed their yield strength, but
usually this is considerably higher than that of a comparable metal
part. 10 mph on smooth pavement is essentially zero stress, so a
sudden catastrophic failure makes no sense... unless something else
happened.
Carbon is not inherently fragile... but it does have failure modes
which are different than metal... basically because it will not absorb
energy via plastic deformation.
Back to the OPs original query, even if we assume that this failure
was due to a random defect, testing would not protect us from this.
Tom Kunich
news:16850ae0-b773-48df...@x5g2000prf.googlegroups.com...
Is it conjecture that carbon fiber wheels need to be handled with extreme
care to prevent damage to the wheels from the steel spoke ends?
Tom Kunich
news:83f9b70f-7f7a-4154...@m16g2000yqc.googlegroups.com...
>
> Carbon forks have been ubiquitous on pretty cheap bikes for many years
> now, and and there is no plague of JRA failures that I'm aware of.
> They will shatter quite nicely if you exceed their yield strength, but
> usually this is considerably higher than that of a comparable metal
> part. 10 mph on smooth pavement is essentially zero stress, so a
> sudden catastrophic failure makes no sense... unless something else
> happened.
All that is true. However, now that my fork has shattered I've been told by
several people that they had the same problem with a sudden complete
destruction. I was emailed before by some guy telling me that his expensive
carbon fiber frame had failed in a similar manner and I rolled my eyes and
didn't believe him. So much for my judgement.
> Carbon is not inherently fragile... but it does have failure modes
> which are different than metal... basically because it will not absorb
> energy via plastic deformation.
What is that supposed to mean? Carbon IS inherently fragile if it is built
overlight. Let's remember that these components are stressed a great deal
more than many people give them credit for. Sudden every day loadings are
much higher than some engineers believe. Hence building these things super
light is problematic.
> Back to the OPs original query, even if we assume that this failure
> was due to a random defect, testing would not protect us from this.
That's true. But we know that the failure mode of materials such as carbon
fiber is sudden and total failure whereas the failure mode of steel is a
relatively slow bend and collapse.
AMuzi
>> All true! I was riding with a friend that had gotten a new Carrera
>> with Campy 11 and Boron wheels. It had fancy, curved carbon tubing and
>> weighed around 14 pounds. I was riding my allez steel which weighs
>> about 22 pounds naked, but usually with with two bottles and a seat
>> pack it weighs over 28 pounds. I told him that with his fancy super
>> expensive bike, he wasn't riding any faster than me. He responded,
>> "...but I look good, Andres".
Tom Kunich wrote:
> This is starting to become shocking. Why would anyone spend a great deal
> of money for no apparent reason other than to look like they've spent a
> great deal of money?
Swarovsky, Gucci, Waterman, Blancpain, Mercedes and Ernesto
Colnago seem to understand this. Try to keep up.
thirty-six
> "Ron Ruff" <rruffrr...@yahoo.com> wrote in message
Other than fracture failure caused by embrittlement from overbrazing,
curved steel forks 'fail' only when crashed. Except this is not
failure, it is designed collapse. You are going to be off the saddle
and on the ground anyway when you do bend a well brazed pair of steel
forks. If they fail without significant impact, they were built wrong.
Tom Kunich
news:258aa95d-9dce-478d...@21g2000yqj.googlegroups.com...
>
> You are going to be off the saddle
> and on the ground anyway when you do bend a well brazed pair of steel
> forks. If they fail without significant impact, they were built wrong.
Well, that's the point I was trying to make. Carbon fork failures are well
understood by the people making these forks yet and hence you can't trust
what's going to happen when you use them.
Tom Kunich
news:hgoi2l$hth$1...@news.eternal-september.org...
Most of those people make equipment that is superior and hence cost more to
manufacture. My point is that when you have a device which is NOT superior
that is more expensive to build and is being built because people are
willing to pay more simply to SAY they're paying more....
What's more, you are someone that really understands bicycles very well.
Weren't you the Basso importer at least for awhile?
Tom Kunich
news:LNudnaWzGJkVULLW...@earthlink.com...
Sorry: Carbon fork failures ARE NOT well understood.
Anton Berlin
> Sorry: Carbon fork failures ARE NOT well understood.
Especially when they are make believe.
Fantasy fork failures are as elusive as fantasy miles and fantasy
weight loss or fantasy inventions or fantasy girlfriend in Canada that
you only drafted off of for 300 meters.
Frank Krygowski
Unfortunately, I was the owner of a not-so-well-built pair of steel
forks. They lasted for decades on our tandem, but when they snapped
off at a pothole, there was no warning.
The only lesson I have is, don't buy a custom tandem built by a guy
named Jim Bradford. Or at least, don't buy the last bike he builds
just before leaving for his honeymoon.
He used blades with wall thickness only 1/3 that of tandem gage forks
- something I couldn't determine until too late. :-(
- Frank Krygowski
andre...@aol.com
> <andresm...@aol.com> wrote in message
rolex vs seiko, toyota vs mercedez,. kmart jeans vs calvin klein;
shall I go on. Of people will argue that the more expensive product
offers better performance. Could be, however do they benefit from the
better performance? The role of corporate advertisement is to generate
desire, pure and simple. People will buy unobtainium things because
advertisers spend tremendous amounts of efforts to tempt the most
resisting mind.
We buy carbon wheels because advertisers make them desirable. The more
desirable, the more expensive.
N8N
I agree with a lot of that. I do prefer some "higher end" products;
e.g. I'm wearing an old Longines wristwatch right now rather than a
new Timex, and I'm driving an old Porsche rather than a new anything
(OK, that is mostly because I can't afford a new "anything good")
simply because I like them; I don't delude myself that I'm getting
significantly more "performance" from either, although I have a gut
feeling that either will last longer than a newer, cheaper
equivalent. On the flip side I have started buying Wrangler jeans
because even Levis seem to have become more cheaply made over the last
couple years, to the point where I suspect the Wranglers are actually
a better quality product, and I can get Wranglers at Target
(pronounced tar-jhay, of course) for cheaper than just about any other
brand.
nate
Tom Kunich
news:aa000a33-204a-407a...@j24g2000yqa.googlegroups.com...
>
> rolex vs seiko, toyota vs mercedez,. kmart jeans vs calvin klein;
> shall I go on.
You're missing the point I think. Mercendes and Rolex are supposed to be a
superior product hence the increase in cost. Mind you it doesn't matter that
the difference is so minor as to be almost negligable - people are made to
think they're getting something better.
> People will buy unobtainium things because
> advertisers spend tremendous amounts of efforts to tempt the most
> resisting mind.
I agree but we aren't discussing this are we? My point was about people who
know very well that the very expensive super light wheels aren't improving
their own performance since they only have an effect on the very cutting
edge of performance. They're buying these wheels simply to have the highest
zoot.
> We buy carbon wheels because advertisers make them desirable. The more
> desirable, the more expensive.
I have seen your postings and I have a difficult time thinking that you're
being led about by the nose.
Anton Berlin
>
> - Show quoted text -
Just an example my Sea-Dweller is worth 3x what I paid for it 14 years
ago. My last Porsche maintained it's value over a 10 yr period, and I
sold it for what I paid for it. And not that I give a shit but the
guys that bought Supras in the 90s are selling their cars for 2x to 3x
what they paid for them while the similar Lexus is garbage now.
PS Kunich the plural of Mercedes is Mercs and you have yet to produce
these photos of the fork/wreck so no one is putting any cred into what
you write. And using the old 'killfile' excuse won't work becuase
everyone in here is writing about what a lying coward you are.
z
There is some truth in what you say. I doubt a nice bike has ever been
the reason someone got laid. Probably the contrary if married.
AMuzi
DougC
>
> .... On the flip side I have started buying Wrangler jeans
> because even Levis seem to have become more cheaply made over the last
> couple years, to the point where I suspect the Wranglers are actually
> a better quality product, and I can get Wranglers at Target
> (pronounced tar-jhay, of course) for cheaper than just about any other
> brand.
>
> nate
In the last couple of years Levi's stopped US production and switched to
foreign labor. Give em some credit however; they were the last major
jeans company with all their production in the US. They just couldn't
afford to hold out any longer.
I switched to these and like em-
http://www.allamericanclothing.com/bottoms.html
specifically the gusset-crotch ones.
~
andre...@aol.com
> <andresm...@aol.com> wrote in message
I obey my thirst.
andre...@aol.com
I want one, is it still available? Do you carry them Andrew?
Nate Nagel
Hah, and it's local!
Sadly, the only people who have ever commented on my bike were guys, my
age or older :( I guess the refinement and prestige of a real loose
ball bottom bracket, like a fine vintage car, are only appreciated by a
select few :P
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
Tim McNamara
<4b06d4f0-dcf6-44f0...@m38g2000yqd.googlegroups.com>,
Scott <hendric...@hotmail.com> wrote:
> On Dec 21, 12:09�am, Jobst Brandt <jbra...@sonic.net> wrote:
> > Ron Ruff wrote:
> > >> The strange way it broke - shooting a 3 or 4 inch piece sideways
> > >> off of the fork - suggests some manufacturing defect.
> > > It doesn't suggest that to me. �You were cruising on smooth
> > > pavement at 10 mph and the fork exploded. �That would suggest to
> > > me that a foreign object was involved... like a stick getting
> > > kicked up and caught in the spokes. �If not that, then someone
> > > shot your fork.
> >
> > You're phishing Ron. �These carbon bikes are unpredictably fragile
> > as has been demonstrated by the many failure reports described here
> > on this newsgroup and seen in pictures.
> >
> > Jobst Brandt
>
> Many failure reports??? How about this, how about we take a poll of
> everyone who has NOT had their fork fail JRA? To say that carbon
> fiber forks are unpredictably fragile is such an overstatement. Even
> I know the odds are nowhere near 50/50 that they'll fail.
The anecdotally reported catastrophic failure rate of CF frames and
forks is dramatically higher than any other frame material.
AMuzi
>>>>> All true! I was riding with a friend that had gotten a new Carrera
>>>>> with Campy 11 and Boron wheels. It had fancy, curved carbon tubing and
>>>>> weighed around 14 pounds. I was riding my allez steel which weighs
>>>>> about 22 pounds naked, but usually with with two bottles and a seat
>>>>> pack it weighs over 28 pounds. I told him that with his fancy super
>>>>> expensive bike, he wasn't riding any faster than me. He responded,
>>>>> "...but I look good, Andres".
>>> Tom Kunich wrote:
>>>> This is starting to become shocking. Why would anyone spend a great
>>>> deal of money for no apparent reason other than to look like they've
>>>> spent a great deal of money?
>> z wrote:
>>> There is some truth in what you say. I doubt a nice bike has ever been
>>> the reason someone got laid. Probably the contrary if married.
> AMuzi <a...@yellowjersey.org> wrote:
>> Hope springs eternal:
http://www.craigslist.org/about/best/wdc/212946173.html
andre...@aol.com wrote:
> I want one, is it still available? Do you carry them Andrew?
Oh, certainly. It wasn't my ad, but I remembered it.
Tim McNamara
<b09afa25-792a-4e0a...@z35g2000prh.googlegroups.com>,
Jay Beattie <jbea...@lindsayhart.com> wrote:
> On Dec 20, 2:10�pm, "hargo...@yahoo.com" <hargo...@yahoo.com> wrote:
> > On Dec 20, 12:19�pm, "Tom Kunich" <tkun...@earthlink.net> wrote:>
> > "AMuzi" <a...@yellowjersey.org> wrote in message
> >
> > >news:hgm0ed$a4h$1...@news.eternal-september.org...
> >
> > > > hargo...@yahoo.com wrote:
> > > >> I was wondering if anyone knows if there has been any testing
> > > >> of the lightweight wheels to show what their strength is...?
> > > >> To date all the focus on lightweight and aerodynamics..?
> >
> > > > Yes:
> > > >http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
> >
> > This is a very good reason why the UCI and or the consumer product
> > safety commisison needs to get involved. Since bike technology is
> > advancing so quickly the industry needs a association similar to
> > the SAE (Society of Automotive Engineers). This way they can meet
> > and help to companies to develop sound manfacturing techniques.
> > Testing standards would also play a major role. I am very surprised
> > that Mavic did not do more testing. Campagnolo spends a lot of time
> > testing their products. There was a picture of Campagnol testing
> > wheels to test the deflection of a wheel.
> >
>
> The CPSC is involved, sort of:
>
> 16 CFR � 1512.13 Requirements for front fork. The front fork shall
> be tested for strength by application of at least 39.5 J (350 in-lb)
> of energy in accordance with the fork test, �1512.18 (k)(1), without
> visible evidence of fracture. Sidewalk bicycles need not meet this
> requirement.
According to the drivers hereabouts, every bike is a sidewalk bike!
> The regulations also require participation in the creation of
> voluntary standards such as the ASTM fork standard (F2274?).
> Dangerous products have to be reported and recalled, etc. So even
> absent a more rigorous CPSC standard, manufacturers have a strong
> incentive to make a durable product to avoid the expense of recalls
> and, of course, lawsuits. Based on my experience representing
> manufacturers, they do a lot of testing, and they are careful.
Put a notch in the CF and then see how it fares. It's a material highly
susceptible to notch effect (in the current formulation; the material
will eventually be improved to reduce or eliminate this problem).
> Manufacturers are also competing for market share, however, and the
> market wants light. As Bontrager put it, "light, strong, cheap, pick
> any two." Frames these days weigh less than the cast-crown SP forks
> I was riding in '78. Those forks lasted me until 2006 -- when I drove
> them in to a garage door opening clamped in to a roof rack. I could
> still use them for driving nails or home protection or a boat anchor.
> Nobody wants those kinds of forks anymore except for the Grant
> Peterson and Surley set, which is a small portion of the market.
A small portion of the racing and wannabe market. A much larger portion
of the rest of the cycling market- commuters, tourists, pleasure riders,
etc. Unfortunately a lot of those folks buy their bikes at Walmart or
Target.
Tim McNamara
AMuzi <a...@yellowjersey.org> wrote:
> harg...@yahoo.com wrote:
> > I was wondering if anyone knows if there has been any testing of the
> > lightweight wheels to show what their strength is...? To date all the
> > focus on lightweight and aerodynamics..?
>
>
> Yes:
> http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
Climb up the URL to http://www.bustedcarbon.com/ and it turns out this
guy is pretty busy with posts. There are some spectacular (and
horrifying) failures.
I have to say, though, I wouldn't expect any bike to be useable after
flying off a roof rack at 75 mph and then getting run over by a Mercedes.
Tim McNamara
Jobst Brandt <jbr...@sonic.net> wrote:
> Ryan Cousineau wrote:
>
> > If for some reason you're looking for unusually strong wheels that
> > are really racy, Zipp makes heavy-duty versions of their more
> > popular wheels. The weight difference is very small.
>
> I don't understand how a broad part of society sees itself as wanting
> or needing to own "really racy" equipment but it appears to be
> universal, whether the family car, home computer, or bicycle for that
> matter. Just look at the huge chromy low profile wheels housewives
> use to drive children to school or go shopping. Quad rumble pipes
> makes their mount sound more like a Peterbilt with Cummins diesel and
> dual stacks than a mundane sedan or station wagon.
>
> Fragile carbon fiber wheels in the multi-thousand dollar range are
> just as important to them while fawning over Lance Armstrong's racing
> accomplishments. Me too, me too! ... "We won today!" speaking of the
> local pro-sport team.
Just human nature's tendency to identify with some others and to compete
with other... others. Banding together promoted survival so the social
genes got passed on.
Tim McNamara
AMuzi <a...@yellowjersey.org> wrote:
"Try to keep up" is exactly the point. The display of wealth is no
different than a male peacock's tailfeather displays. Males with more
"eyes" on their tailfeathers get more mates. People with more
demonstrations of affluence tend to get more mates (literal mates,
friends, business partners, etc.) too. There's an advantage to the
behavior.
Jay Beattie
> In article
> <b09afa25-792a-4e0a-8be9-eba8e58dd...@z35g2000prh.googlegroups.com>,
What I am trying to say is that very few people would pay serious
bread for a set of heavy custom steel forks. The people with that type
of money are buying CF racing bikes -- unless they are Rivendell
buyers or serious tourists. I should have been more clear that I was
not talking about the mid-fi and low-fi bicycle market. Fork materials
in that market segment are all over the place. -- Jay Beattie.
bjwe...@gmail.com
> In article <hgm0ed$a4...@news.eternal-september.org>,
>
> AMuzi <a...@yellowjersey.org> wrote:
> > hargo...@yahoo.com wrote:
> > > I was wondering if anyone knows if there has been any testing of the
> > > lightweight wheels to show what their strength is...? To date all the
> > > focus on lightweight and aerodynamics..?
>
> > Yes:
> >http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
>
> guy is pretty busy with posts. There are some spectacular (and
> horrifying) failures.
>
> I have to say, though, I wouldn't expect any bike to be useable after
> flying off a roof rack at 75 mph and then getting run over by a Mercedes.
Certainly. A quick scan through that blog suggests a lot
(not all) of the pictures are from crashes, and I mean
ones where there is a crash, an impact on the bike,
and it cracks or breaks, as opposed to incidents
where the bike breaks causing a crash. There are
some failures that might be JRA, plus the egregious
R-Sys wheels, but when a bike gets crashed (or hit by
a car!) and breaks, I can't label that a component
failure.
Which means that all I really learn from the blog is
that broken or snapped carbon parts look more exciting
than broken or twisted metal parts, and are more
likely to lead to creation of a blog devoted to same.
I only have one carbon thing because I'm cheap, and
conservative (for ex, I do have a couple of parts that
are light enough that I am reluctant to use them).
However, none of the evidence presented here suggests
that carbon parts are all timebombs. I do think that some
evidence suggests lightweight parts, many of which
are carbon, are overly fragile when ridden hard,
on rough surfaces, or by rough or heavy riders.
This is not unique to carbon. If you're, say, 220 lbs
you shouldn't be riding titanium pedal spindles
either, or using 200 gram aluminum bars on your
cyclocross bike, or using GEL 280 rims. People do
this anyway (except for the GEL rims since they have
gone where the woodbine twineth), and stuff breaks,
regardless of its position in the periodic table.
Ben
Tim McNamara
<5944ba62-f7e6-4678...@u16g2000pru.googlegroups.com>,
"b...@mambo.ucolick.org" <bjwe...@gmail.com> wrote:
I'm about 220 lbs, ride steel frame bikes and have never had a
catastrophic frame or fork failure from an impact to the bike. That
such failures can happen at all with carbon fiber is- to my thinking,
obviously not to others'- completely unacceptable. Hence I do not use
carbon fiber. I can think of no benefit whatsoever from having a frame
or fork shatter. I also don't use ultralight aluminum parts like bars
and stems. In 35+ years I have had two catastrophic failures (thus
far...) including a snapped Viscount BB and a Sun rim which had a spoke
nipple rip through and tear out a chunk of rim bed with it. I've had
three cracked frames, all steel, all of them rideable for many miles
after noticing the cracks (two at the left seatstay/seat tube joint, one
seat tube/BB joint). Steel fails slowly with only occasional exceptions
(Frank's tandem fork, for example); carbon typically fails almost
instantly when it breaks.
Catastrophic failures suck. They are not acceptable no matter the
reason (excepting something extreme like getting run over by a truck or
dropped off a car at 75 mph. There are limits, after all). As I've
said, I think that CF will be improved so that this failure mode is
reduced or eliminated at which point it will be a reasonably material
for the conservative cyclist to use. The same was true of aluminum and
titanium when they were introduced into cycling.
harg...@yahoo.com
I suspect that a lot of the catastrophic failure is ocurring with
composite parts and frames that has been crashed before. One problem
is that no bike shop has the necessary equipment to check a carbon
fiber frame or part. One thing to remember is that tiny micro stress
fractures often occur that is not visible even with optical
magnification.
thirty-six
>
>
>
> "b...@mambo.ucolick.org" <bjwei...@gmail.com> wrote:
> > On Dec 21, 6:36 pm, Tim McNamara <tim...@bitstream.net> wrote:
> > > In article <hgm0ed$a4...@news.eternal-september.org>,
>
> > > AMuzi <a...@yellowjersey.org> wrote:
> > > > hargo...@yahoo.com wrote:
> > > > > I was wondering if anyone knows if there has been any testing
> > > > > of the lightweight wheels to show what their strength is...? To
> > > > > date all the focus on lightweight and aerodynamics..?
>
> > > > Yes:
> > > >http://www.bustedcarbon.com/2009/06/mavic-r-sys-redux.html
>
I'm not aware the original Sun, spun aluminium rims were in any way
deficient when they were introduced. Could you please show me
evidence of aluminium rim failures over a century ago.
cur...@the-md-russells.org
<jbea...@lindsayhart.com> wrote:
>
>What I am trying to say is that very few people would pay serious
>bread for a set of heavy custom steel forks. The people with that type
>of money are buying CF racing bikes -- unless they are Rivendell
>buyers or serious tourists. I should have been more clear that I was
>not talking about the mid-fi and low-fi bicycle market. Fork materials
>in that market segment are all over the place. -- Jay Beattie.
Taking away the mid-fi means, I assume, all of the trend bikes, some
of which may actually stay (metro bikes and semi-low riders that sell
for near or just over a thousand or so). By doing so, you really leave
it to the tourists and very serious commuters and many of the latter
prefer well running throwaways in many situations, rather than putting
an expensive bike at risk. Arguably, the Bike Friday and equivalent
group of commuters is a set of serious commuters than use steel forks.
That group would probably also argue that 'heavy' is heavy only in
relationship to the racing crowd.
The problem is the bike shop nexus. The bikes have to reach sales of
sufficient critical mass that the bike shops can carry them, make
money and make them readily available. Otherwise, the person either
buys what is available or has to have the inclination and expertise to
order and wait. That is a small group of any set of cyclists. The
non-racing crowd that purchase high-end road machines probably stress
the bikes less than racers, tourists or commuters anyway, so carbon
forks are probably just fine for that purpose.
My last bike purchased was a mix of steel and carbon because I didn't
expect to put that much stress on the bike over its lifetime (the Bike
Friday gets the biggest beating) and that was what was available at a
friend's bike shop. I would have preferred all steel, but it wasn't
sufficiently an issue for the intended use and there were no quality
all steel bikes, especially with brifters. So I have what I have. If I
were ordering a touring frame again, yeah, I would special order an
all steel frame. Probably with all those 'heavy' parts, it would weigh
at or about 30 pounds for the 25" bike part of the assembly and that
would be completely irrelevant when it was actually loaded. I could
start another thread on people that spend a lot of money for the very
lightest touring bike and then buy the largest possible pannier
combination to further impress their friends...
Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...
Scott
So? It's anecdotal. You said so yourself.
How about the anecdotally reported non-failure of CF frames and
forks? Oh, that's right, nobody talks about that sort of thing.
Bob Schwartz
> Catastrophic failures suck. They are not acceptable no matter the
> reason (excepting something extreme like getting run over by a truck or
> dropped off a car at 75 mph. There are limits, after all). As I've
> said, I think that CF will be improved so that this failure mode is
> reduced or eliminated at which point it will be a reasonably material
> for the conservative cyclist to use. The same was true of aluminum and
> titanium when they were introduced into cycling.
Tim, maybe you're not riding enough.
I've had all sorts of catastrophic failures, all of them
involving stuff that everybody reading this is familiar with.
With respect to frames and forks, I've sent a bunch to the
landfill and each and every one was factory produced steel.
Granted I've never kissed pavement because of a steel failure,
but I've had to resort to cell phone rescues.
The stuff that used to send me to the ground was cranks, and
the solution was simple, don't ride stuff until failure. When
my mileage was high I would buy new cranks every year and just
pitch whatever was oldest. I rationalized this by reasoning
that my skin and bones were worth more than the value of an
extra year out of the cranks.
I'm a cheap bastard, I buy low end bikes. There is no way you
can tell me that factory produced steel bikes are more reliable
than factory aluminum or carbon. Just no way. Comparing a guy
with a torch and carbon stuff where low weight is used as a
marketing feature is different. But in terms of the stuff that
99% of cyclists ride I think that the world would be awash with
steel bike failures if only that 99% would take the bike off
the hook and ride it. The fact that they don't is why steel
bikes are as successful as they are.
Bob Schwartz
Frank Krygowski
wrote:
>
>
> Tim, maybe you're not riding enough.... But in terms of the stuff that
> 99% of cyclists ride I think that the world would be awash with
> steel bike failures if only that 99% would take the bike off
> the hook and ride it. The fact that they don't is why steel
> bikes are as successful as they are.
Hmm. As I recall, people like Ian Hibbel, John Rakowski and Dervla
Murphy either rode, or still ride, steel bikes with reasonable
success. Their bikes never spent much time hanging from hooks.
I suppose if people tried those folks' rides on a 1975 department
store steel bike, success would be less likely. But in general, if a
person stays away from shedding the last three pounds of bike weight,
bikes seem to be reliable. Even if they're steel!
And to the degree that carbon fiber has a problem, I think that final
three pounds is the reason. Carbon fiber is used to push to the edge
of minimum weight. In doing so, designers sacrifice the ability to
handle non-standard loads or conditions.
Would you clamp low rider racks onto a carbon fork? I certainly
wouldn't.
- Frank Krygowski
Donald Munro
> I'm about 220 lbs, ride steel frame bikes and have never had a
> catastrophic frame or fork failure from an impact to the bike. That
> such failures can happen at all with carbon fiber is- to my thinking,
> obviously not to others'- completely unacceptable.
Why don't you rbt fatties lose some weight. Then your bikes wouldn't break.
Jobst Brandt
That may sound reasonable but it is no protection because, as I
mentioned, cranks fail crosswise from the load of the rider, mainly
when standing, as the foot steps off to the other foot at the bottom
of the stroke, something that hardly occurs when seated, but more
likely when sprinting or climbing. That is also why "mashing big
gears" is not the cause of crank failures because that is a in-plane
bending load for which cranks are at least eight times stronger (large
cross section) than crosswise because stress is related to the third
power of the cross sectional dimension.
Cranks don't suddenly fail without crack initiation, something that
takes hundreds of miles to develop. As I have often mentioned,
inspecting my cranks for cracks every Sunday morning in bright
sunlight with a magnifying glass uncovered cracks at least once every
10,000 miles for 30 years until I modified the pedal attachment and
have had no failures for years since.
If crank failures were understood by the industry, they would have
gone away long ago. The beliefs of the designers get passed on to the
riding public and they retell them on wreck.bike.
Jobst Brandt
Anton Berlin
>
> - Show quoted text -
What is the crank modification?
Bob Schwartz
> Cranks don't suddenly fail without crack initiation, something that
> takes hundreds of miles to develop. As I have often mentioned,
> inspecting my cranks for cracks every Sunday morning in bright
> sunlight with a magnifying glass uncovered cracks at least once every
> 10,000 miles for 30 years until I modified the pedal attachment and
> have had no failures for years since.
Sure, I understand that. I just made an economic decision.
Cranks are cheap, at least the ones I buy are, and the
value of the use I lost by replacing them on a schedule vs
replacing them based on regular inspection wasn't worth the
time and bother of regular inspection.
Bob Schwartz
Anton Berlin
a. the stresses that fat fred put on a bike will always be a fraction
of Thor or Cancellera etc.
b. well designed carbon frames have greater (name any metric) than
steel, alum, nivacrom etc. Other than notch sensitivity I consider my
Ridleys bulletproof in every way. The days of 'Kestral explosions'
are 15 years down the road.
c. guys that push the limits with carbon spoked wheels (like r-sys)
are asking for trouble but at the same time H3s are probably the
strongest most aero wheels in the world and $ per second are hands
down the best. They are 'clydesdale' certified
d. mixed materials like Kunichs imagined broken fork are the most
likely to break, you'd have a tough time catching me on a steel or
alloy steer tube fork that is glued to carbon blades. Kunich at least
picked a likely fork to lie about.
e. I doubt my Ouzo or Ridley full carbon forks will ever fail without
some precursor that would have failed earlier (and we're talking
fractions of a second) a mixed or all steel or all alum fork.
f. I've ridden titanium pedals my entire life and never had a failure
yet. (CampySR, Time Ti/Mag, and Keo Ti) If anyone was going to break
one of these pedals it would be Andy Paulin or me.
Jobst is right, inspection is crucial. I caught a Max fork in mid
failure, not a bad braze but a result of the poor design of the Max
fork crown.
Clamping anything to a carbon frame (like a rack) is stupid. They're
just not made for that.
bar
so clamping an alum stem on a carbon steerer is stupid? i'm calling
BULLSHIT, bro
Jobst Brandt
"replacing them on a schedule" as I pointed out is an unknown period
that cannot be readily predicted even roughly. That is why I gave it
some thought and encouraged crank manufacturers to not put a vanity
groove down the lateral face of cranks and, without success, to get
conical faces on pedal spindles to fit like conical lug nuts on cars.
Jobst Brandt
Jobst Brandt
>> ....
>> Cranks don't suddenly fail without crack initiation, something that
>> takes hundreds of miles to develop. As I have often mentioned,
>> inspecting my cranks for cracks every Sunday morning in bright
>> sunlight with a magnifying glass uncovered cracks at least once
>> every 10,000 miles for 30 years until I modified the pedal
>> attachment and have had no failures for years since.
>> If crank failures were understood by the industry, they would have
>> gone away long ago. The beliefs of the designers get passed on to
>> the riding public who retell them on wreck.bike making them
>> folklore.
> What is the crank modification?
http://www.chiark.greenend.org.uk/~damerell/bikes/brandt-cranks.jpg
A basic design rule is that radial loads should not be supported on
threaded shafts (as pedals are), something engineers of the bicycle
industry missed in school. I may be generous in calling them
engineers, whereas they are probably more like hand push lawn mower
mechanics, something that was part of bicycle shop business more than
40 years ago.
Jobst Brandt
Jay Beattie
> a. the stresses that fat fred put on a bike will always be a fraction
> of Thor or Cancellera etc.
> b. well designed carbon frames have greater (name any metric) than
> steel, alum, nivacrom etc. Other than notch sensitivity I consider my
> Ridleys bulletproof in every way. The days of 'Kestral explosions'
> are 15 years down the road.
> c. guys that push the limits with carbon spoked wheels (like r-sys)
> are asking for trouble but at the same time H3s are probably the
> strongest most aero wheels in the world and $ per second are hands
> down the best. They are 'clydesdale' certified
> d. mixed materials like Kunichs imagined broken fork are the most
> likely to break, you'd have a tough time catching me on a steel or
> alloy steer tube fork that is glued to carbon blades. Kunich at least
> picked a likely fork to lie about.
> e. I doubt my Ouzo or Ridley full carbon forks will ever fail without
> some precursor that would have failed earlier (and we're talking
> fractions of a second) a mixed or all steel or all alum fork.
> f. I've ridden titanium pedals my entire life and never had a failure
> yet. (CampySR, Time Ti/Mag, and Keo Ti) If anyone was going to break
> one of these pedals it would be Andy Paulin or me.
Or me. I've broken two Cro-Mo (Look, DuraAce) spindles and one Ti.
Six or seven cranks, bars, seat posts, BBs (several), axles, four or
five frames (steel and Al). If you ride something long enough and put
it through enough fatigue cycles, it will fail. CF is less likely to
fail due to fatigue but is less resistant to mechanical damage.
In my book, a TdF rider is less likely to break a CF frame than a
mileage-crazy Cat 3 who will own the bike for more than a season and
will probably abuse it in ways unimagined by a pro team mechanic.
As for (e) above, a single event capable of failing a well-made CF
fork would also eject the rider (e.g. a wall impact) -- so whether the
fork survived the event would not really matter. The problem with CF
is that mechanical damage from a relatively innocuous event (dropping
the bike/mis-clamping in roof rack) may cause the fork to fail later
without an impact -- Tom's JRA scenario. That would not happen with
steel. Even if you bent your steel forks, you could safely ride home
-- or even ride forever if you were O.K. with the new rake. I hit a
car and turned my old steel road bike in to a crit bike and rode that
for years before it broke elsewhere. Not that I would want to own that
bike today, but it was durable -- and it was the same sort of bike
being raced by everyone, plus or minus a few drill holes. Back then,
minor geometry differences, lug filing and paint jobs were about all
that separated one bike from another. -- Jay Beattie.
Sandy
They only race hippo-crits.
--
Bonne route !
Sandy
Verneuil-sur-Seine FR
Frank Krygowski
> . Even if you bent your steel forks, you could safely ride home
> -- or even ride forever if you were O.K. with the new rake. I hit a
> car and turned my old steel road bike in to a crit bike and rode that
> for years before it broke elsewhere.
Many years ago, I happened to come across a young couple passing
though our town with fully loaded panniers. Turns out they were
novice bicyclists who had just married, and were riding from
California to New York City for their honeymoon.
I looked at the woman's bike, and noted that the fork appeared to have
bent back a bit, and the frame tubes were bent just behind the head
tube. "Oh yeah, I wasn't paying attention and I ran into a car on our
second day out." But the bike still rode fine, she said.
The bike had done about 3000 miles, heavily loaded, with that clearly
visible damage. I wonder what the effect would have been with a
carbon fork and frame?
But of course, you wouldn't attempt that trip with such a bike. No
way to mount wide tires, no way to mound decent fenders, no way to
mount front racks, maybe not even rear racks. Hell, even a headlight
might upset its delicate sensibilities.
- Frank Krygowski
AMuzi
ha ha ha
Tim is a fit but tall 220, not a 'fattie'.
thirty-six
Er, yes the same manufacturers made bicycles and mowers. Atco and
Puch (?).
Frank Krygowski
> a. the stresses that fat fred put on a bike will always be a fraction
> of Thor or Cancellera etc.
Doubtful. Take a 250 pound tourist with an 80 pound camping load and
let him ride some really rough roads. I think you'll see lots of
interesting stress levels.
> b. well designed carbon frames have greater (name any metric) than
> steel, alum, nivacrom etc.
Ductility?
> Clamping anything to a carbon frame (like a rack) is stupid. They're
> just not made for that.
Yep, they're too delicate. They're intended only for situations where
the loads always come from a few carefully anticipated directions,
where the bike is bubble wrapped for transport, where nothing
extraneous may ever be attached to the frame and fork, and where the
bike will never be used for anything more practical or adventurous
than trying to be a little faster than someone else who's also willing
to humor such a fragile toy.
Not that there's anything wrong with that! ;-)
- Frank Krygowski