Comparison of Auminium, Steel and Carbon forks?

[[email protected]]

On Apr 19, 9:48 am, Mike Rocket J Squirrel
<[email protected]> wrote:
> On 4/19/2008 6:31 AM Hobbes@spnb&s.com wrote:
>
>
> > Yeah, there are no impartial tests that establish the relative characteristics
> > of forks made from different materials. Such a test would have to hold all other
> > variables constant in a way that simply isn't possible.
>
> How come? Not arguing, just curious. Seems (to me, not a mechanical
> engineer nor wrench) that one could get three forks with same geometry,
> tilt at proper head tube angle, clamp dropouts to shaker table, add mass
> loading from above, hang some accelerometers on the stem and let 'er rip.
> Just to see, y'know?

I think this would be the likely result: Whoever did the test would
find _some_ element in the data that they thought made their favorite
fork look good. They'd point to that and say "See?? PROOF!"

If the test were properly advertised, they'd suck in thousands of guys
who barely passed middle school science, and the placebo effect would
work wonderfully for them. They'd feel _so_ much more comfortable -
because they'd know they were supposed to feel _so_ much more
comfortable.

Meanwhile, we'd dissect the test results here, trying to determine
whether the particular data element really meant anything practical,
and whether it was worth any related detriments. We'd have lots of
"I know what _I_ feel!" folks on one side, and probably a good many
engineers on the other side.

And whatever side Jobst Brant was on, jim beam would be rabidly on the
other. ;-)

- Frank Krygowski

 

[[email protected]]

On Apr 18, 8:41 pm, jim beam <[email protected]> wrote:
> blackhead wrote:
> > Are there any impartial tests that have been done on Auminium, Steel
> > and Carbon forks? Some people say carbon absorbs vibration better than
> > steel and Aluminium, others say it makes little difference... etc etc
>
> the best "impartial" test you can do is ride them yourself and compare.
> not something some people with mere opinions are prone to do.

The best impartial test would be to take a given bike, and install
various forks of identical geometry. Keep everything else exactly the
same. Have several riders (say, at least five) ride the bike with
each fork, and report on their impressions.

BUT you must mix the order in which the forks are tested, and most
important, you must cover the forks so the test is blind. Otherwise
the rider will be swayed by his preconceptions.

The placebo effect is powerful. Any test that hopes to remove bias,
but relies on people's perceptions, has to account for the placebo
effect and disable it as much as possible.

- Frank Krygowski

 

[Dan O]

On Apr 19, 6:48 am, Mike Rocket J Squirrel
<[email protected]> wrote:
> On 4/19/2008 6:31 AM Hobbes@spnb&s.com wrote:
>
>
>
> > On Fri, 18 Apr 2008 13:58:51 -0800, agcou <[email protected]> wrote:
>
> >> On Thu, 17 Apr 2008 19:55:23 -0400, Hobbes@spnb&s.com wrote:
>
> >>> On Thu, 17 Apr 2008 15:23:53 -0700 (PDT), blackhead <[email protected]>
> >>> wrote:
>
> >>>> Are there any impartial tests that have been done on Auminium, Steel
> >>>> and Carbon forks? Some people say carbon absorbs vibration better than
> >>>> steel and Aluminium, others say it makes little difference... etc etc
> >>> The differences of design, materials quality and manufacture are greater than
> >>> the differences in the materials themselves. Even in weight there is an
> >>> intersection between the three. I've got bikes with all three and they've all
> >>> got something going for them.
>
> >>> Really depends on what you're doing with the bike and which forks you're
> >>> choosing from.
> >> Did you read the OP's question?
>
> > Yeah, there are no impartial tests that establish the relative characteristics
> > of forks made from different materials. Such a test would have to hold all other
> > variables constant in a way that simply isn't possible.
>
> How come? Not arguing, just curious. Seems (to me, not a mechanical
> engineer nor wrench) that one could get three forks with same geometry,
> tilt at proper head tube angle, clamp dropouts to shaker table, add mass
> loading from above, hang some accelerometers on the stem and let 'er rip.
> Just to see, y'know?
>

I've only ever ridden steel (and some of that plenty cheesy), but it
seems to me the problem with this kind of test is that the chosen
"geometry, tilt, load, etc." - not to mention thickness, etc. - might
favor one material over another, and may or may not be suitable
parameters for a given bike, rider, and purpose. And then the matter
of translating measured results into characteristics favorable for
riding on... And then it also occurs to me that a shaker table is
quite a different thing than a bicycle wheel.

This kind of testing might be okay for a big manufacturer's R&D
(although there goes "impartial" out the window if the marketing dept
has any influence ;-), but for choosing what to ride on, the proof is
(always) in the pudding.

 

[Michael Press]

In article <[email protected]>,
Mike Rocket J Squirrel <[email protected]> wrote:

> On 4/19/2008 6:31 AM Hobbes@spnb&s.com wrote:
>
> > On Fri, 18 Apr 2008 13:58:51 -0800, agcou <[email protected]> wrote:
> >
> >> On Thu, 17 Apr 2008 19:55:23 -0400, Hobbes@spnb&s.com wrote:
> >>
> >>> On Thu, 17 Apr 2008 15:23:53 -0700 (PDT), blackhead <[email protected]>
> >>> wrote:
> >>>
> >>>> Are there any impartial tests that have been done on Auminium, Steel
> >>>> and Carbon forks? Some people say carbon absorbs vibration better than
> >>>> steel and Aluminium, others say it makes little difference... etc etc
> >>> The differences of design, materials quality and manufacture are greater than
> >>> the differences in the materials themselves. Even in weight there is an
> >>> intersection between the three. I've got bikes with all three and they've all
> >>> got something going for them.
> >>>
> >>> Really depends on what you're doing with the bike and which forks you're
> >>> choosing from.
> >> Did you read the OP's question?
> >
> > Yeah, there are no impartial tests that establish the relative characteristics
> > of forks made from different materials. Such a test would have to hold all other
> > variables constant in a way that simply isn't possible.
>
> How come? Not arguing, just curious. Seems (to me, not a mechanical
> engineer nor wrench) that one could get three forks with same geometry,
> tilt at proper head tube angle, clamp dropouts to shaker table, add mass
> loading from above, hang some accelerometers on the stem and let 'er rip.
> Just to see, y'know?

Let me know when carbon fibre forks are made in this geometry,
or Al for that matter.
<http://sheldonbrown.org/raleigh-international/index.html>

--
Michael Press

 

[Michael Press]

In article
<bb2ff521-94be-4452-8ad2-b913b474af17@k37g2000hsf.googlegroups.com>,
[email protected] wrote:

> And whatever side Jobst Brant was on, jim beam would be rabidly on the
> other. ;-)

Seems Jobst Brandt does not take sides. jim beam makes
discussions seem a matter of taking sides.

--
Michael Press

 

[landotter]

On Apr 17, 5:23 pm, blackhead <[email protected]> wrote:
> Are there any impartial tests that have been done on Auminium, Steel
> and Carbon forks? Some people say carbon absorbs vibration better than
> steel and Aluminium, others say it makes little difference... etc etc

I prefer a composite made from the woven pubic hair of a virgin
combined with celluloid. It's a thrilling ride with the liveliness of
a ping pong ball.

 

[[email protected]]

On Apr 19, 10:18 am, Mike Rocket J Squirrel
<[email protected]> wrote:
> On 4/19/2008 6:57 AM [email protected] wrote:
>
>
>
> > On Apr 19, 9:48 am, Mike Rocket J Squirrel
> > <[email protected]> wrote:
> >> On 4/19/2008 6:31 AM Hobbes@spnb&s.com wrote:
>
> >>> On Fri, 18 Apr 2008 13:58:51 -0800, agcou <[email protected]> wrote:
> >>>> On Thu, 17 Apr 2008 19:55:23 -0400, Hobbes@spnb&s.com wrote:
> >>>>> On Thu, 17 Apr 2008 15:23:53 -0700 (PDT), blackhead <[email protected]>
> >>>>> wrote:
> >>>>>> Are there any impartial tests that have been done on Auminium, Steel
> >>>>>> and Carbon forks? Some people say carbon absorbs vibration better than
> >>>>>> steel and Aluminium, others say it makes little difference... etc etc
> >>>>> The differences of design, materials quality and manufacture are greater than
> >>>>> the differences in the materials themselves. Even in weight there is an
> >>>>> intersection between the three. I've got bikes with all three and they've all
> >>>>> got something going for them.
> >>>>> Really depends on what you're doing with the bike and which forks you're
> >>>>> choosing from.
> >>>> Did you read the OP's question?
> >>> Yeah, there are no impartial tests that establish the relative characteristics
> >>> of forks made from different materials. Such a test would have to hold all other
> >>> variables constant in a way that simply isn't possible.
> >> How come? Not arguing, just curious. Seems (to me, not a mechanical
> >> engineer nor wrench) that one could get three forks with same geometry,
> >> tilt at proper head tube angle, clamp dropouts to shaker table, add mass
> >> loading from above, hang some accelerometers on the stem and let 'er rip.
> >> Just to see, y'know?
>
> >> --
> >> Mike "Rocket J Squirrel"
>
> > That won't tell you much about the materials though. You could do the
> > same test with three carbon forks with the same geometry and get
> > vastly different results.
>
> I assume we're not saying that quality control is so poor that three forks
> of the same brand/model would not measure the same. More like small
> changes in fork shapes, cross-sections, etc., have a bigger influence on
> vibration transmission than the the material itself. So the chances of
> finding three forks of different materials which are built sufficiently
> similar that those other factors will not contribute to the results is
> slim to none.
> --
> Mike "Rocket J Squirrel"

Right. Three forks of the same make and model should be exactly the
same (although variance is likely to go up substantially at the bottom
end of the market), but you can't just test one carbon fork next to
one aluminum fork and say that the difference is the material.
Whatever vibration parameter you're measuring is going to have a big
enough range across different models of carbon forks that it's going
to overlap with the range across different models of aluminum forks.

 

[jim beam]

[email protected] wrote:
> On Apr 19, 10:18 am, Mike Rocket J Squirrel
> <[email protected]> wrote:
>> On 4/19/2008 6:57 AM [email protected] wrote:
>>
>>
>>
>>> On Apr 19, 9:48 am, Mike Rocket J Squirrel
>>> <[email protected]> wrote:
>>>> On 4/19/2008 6:31 AM Hobbes@spnb&s.com wrote:
>>>>> On Fri, 18 Apr 2008 13:58:51 -0800, agcou <[email protected]> wrote:
>>>>>> On Thu, 17 Apr 2008 19:55:23 -0400, Hobbes@spnb&s.com wrote:
>>>>>>> On Thu, 17 Apr 2008 15:23:53 -0700 (PDT), blackhead <[email protected]>
>>>>>>> wrote:
>>>>>>>> Are there any impartial tests that have been done on Auminium, Steel
>>>>>>>> and Carbon forks? Some people say carbon absorbs vibration better than
>>>>>>>> steel and Aluminium, others say it makes little difference... etc etc
>>>>>>> The differences of design, materials quality and manufacture are greater than
>>>>>>> the differences in the materials themselves. Even in weight there is an
>>>>>>> intersection between the three. I've got bikes with all three and they've all
>>>>>>> got something going for them.
>>>>>>> Really depends on what you're doing with the bike and which forks you're
>>>>>>> choosing from.
>>>>>> Did you read the OP's question?
>>>>> Yeah, there are no impartial tests that establish the relative characteristics
>>>>> of forks made from different materials. Such a test would have to hold all other
>>>>> variables constant in a way that simply isn't possible.
>>>> How come? Not arguing, just curious. Seems (to me, not a mechanical
>>>> engineer nor wrench) that one could get three forks with same geometry,
>>>> tilt at proper head tube angle, clamp dropouts to shaker table, add mass
>>>> loading from above, hang some accelerometers on the stem and let 'er rip.
>>>> Just to see, y'know?
>>>> --
>>>> Mike "Rocket J Squirrel"
>>> That won't tell you much about the materials though. You could do the
>>> same test with three carbon forks with the same geometry and get
>>> vastly different results.
>> I assume we're not saying that quality control is so poor that three forks
>> of the same brand/model would not measure the same. More like small
>> changes in fork shapes, cross-sections, etc., have a bigger influence on
>> vibration transmission than the the material itself. So the chances of
>> finding three forks of different materials which are built sufficiently
>> similar that those other factors will not contribute to the results is
>> slim to none.
>> --
>> Mike "Rocket J Squirrel"
>
> Right. Three forks of the same make and model should be exactly the
> same (although variance is likely to go up substantially at the bottom
> end of the market), but you can't just test one carbon fork next to
> one aluminum fork and say that the difference is the material.

but previously you were saying there would be "vastly different results"
- which of these conflicting statements would you have us believe?


> Whatever vibration parameter you're measuring is going to have a big
> enough range across different models of carbon forks that it's going
> to overlap with the range across different models of aluminum forks.

do you know that for fact? or are you simply presenting presumption as
fact? [rhetorical]

 

[Ben C]

On 2008-04-20, [email protected] <[email protected]> wrote:
[...]
> Right. Three forks of the same make and model should be exactly the
> same (although variance is likely to go up substantially at the bottom
> end of the market), but you can't just test one carbon fork next to
> one aluminum fork and say that the difference is the material.
> Whatever vibration parameter you're measuring is going to have a big
> enough range across different models of carbon forks that it's going
> to overlap with the range across different models of aluminum forks.

Sometimes different materials dictate a different shape.

For example, I think I'm right in saying that if you make an aluminium
fork as flexy as you can make a steel one the aluminium one will fatigue
badly. So you have to make it a bit thicker and/or fatter and stiffer.
Sure you _could_ make a fork just as stiff out of steel, but you don't
have to and might not.

So it's better to compare complete forks as sold and then say something
like "out of the 100 forks tested, the CF ones mostly absorbed vibration
better than the Al ones".

 

[[email protected]]

On Apr 20, 11:33 am, Ben C <[email protected]> wrote:
>
>
> ... So it's better to compare complete forks as sold and then say something
> like "out of the 100 forks tested, the CF ones mostly absorbed vibration
> better than the Al ones".

But only if that's actually true; and only if it's true to a degree
beyond "negligible."

I think enforcing those two points would eliminate most bicycle
component advertising and hype.

(Ceramic bearings, anyone?)

- Frank Krygowski

 

[Ben C]

On 2008-04-20, [email protected] <[email protected]> wrote:
> On Apr 20, 11:33 am, Ben C <[email protected]> wrote:
>>
>>
>> ... So it's better to compare complete forks as sold and then say something
>> like "out of the 100 forks tested, the CF ones mostly absorbed vibration
>> better than the Al ones".
>
> But only if that's actually true; and only if it's true to a degree
> beyond "negligible."

Of course only if it's true!

> I think enforcing those two points would eliminate most bicycle
> component advertising and hype.
>
> (Ceramic bearings, anyone?)

Ceramic bearings are much more obviously BS because it's well known that
on any decently maintained bike only a tiny amount of power is lost to
bearing drag. So it's a solution in search of a problem.

I would expect there to be much more likely to be non-negligible
differences between forks.

 

[[email protected]]

Ben C? wrote:

> [...]

>> Right. Three forks of the same make and model should be exactly
>> the same (although variance is likely to go up substantially at the
>> bottom end of the market), but you can't just test one carbon fork
>> next to one aluminum fork and say that the difference is the
>> material. Whatever vibration parameter you're measuring is going
>> to have a big enough range across different models of carbon forks
>> that it's going to overlap with the range across different models
>> of aluminum forks.

> Sometimes different materials dictate a different shape.

> For example, I think I'm right in saying that if you make an
> aluminium fork as flexy as you can make a steel one the aluminium
> one will fatigue badly. So you have to make it a bit thicker and/or
> fatter and stiffer. Sure you _could_ make a fork just as stiff out
> of steel, but you don't have to and might not.

> So it's better to compare complete forks as sold and then say
> something like "out of the 100 forks tested, the CF ones mostly
> absorbed vibration better than the Al ones".

Not to overlook that traditional steel forks had weaker (thinner wall)
steertubes and that most fork flex arose there. This was most visible
by holding the brake locked while rocking the bicycle fore and aft.
This was borne out by the fretting head bearing dimples because most
of this "fork flex" caused the fork crown to rock fore and aft.
Springs are usually made of steel and for that reason other material
steer tubes will have different flexure response.

Beyond that assessment, perceived road shock is primarily the axial
component of vibration traveling to hen handlebars and this is less
affected by steertube or even fork blade flex. I think this
assessment of ride comfort is barking up the wrong tree, so to speak.

Jobst Brandt

 

[jim beam]

Ben C wrote:
<snip for clarity>

>
> I would expect there to be much more likely to be non-negligible
> differences between forks.


of course. krygowski, being an intelligent, informed engineering
professor with access to the correct instrumentation, already the owner
of a cross-section of different forks, a sound knowledge of the
principles, and with an open, inquiring mind, has already tested this
position and is simply waiting for an opportunity to publish his
results. or he's simply an idiot voicing underinformed opinion as fact
and who has no inclination to actually test any damned thing that could
possibly upset his comfy luddite little world.

 

[jim beam]

[email protected] wrote:
> Ben C? wrote:
>
>> [...]
>
>>> Right. Three forks of the same make and model should be exactly
>>> the same (although variance is likely to go up substantially at the
>>> bottom end of the market), but you can't just test one carbon fork
>>> next to one aluminum fork and say that the difference is the
>>> material. Whatever vibration parameter you're measuring is going
>>> to have a big enough range across different models of carbon forks
>>> that it's going to overlap with the range across different models
>>> of aluminum forks.
>
>> Sometimes different materials dictate a different shape.
>
>> For example, I think I'm right in saying that if you make an
>> aluminium fork as flexy as you can make a steel one the aluminium
>> one will fatigue badly. So you have to make it a bit thicker and/or
>> fatter and stiffer. Sure you _could_ make a fork just as stiff out
>> of steel, but you don't have to and might not.
>
>> So it's better to compare complete forks as sold and then say
>> something like "out of the 100 forks tested, the CF ones mostly
>> absorbed vibration better than the Al ones".
>
> Not to overlook that traditional steel forks had weaker (thinner wall)
> steertubes and that most fork flex arose there. This was most visible
> by holding the brake locked while rocking the bicycle fore and aft.
> This was borne out by the fretting head bearing dimples because most
> of this "fork flex" caused the fork crown to rock fore and aft.
> Springs are usually made of steel and for that reason other material
> steer tubes will have different flexure response.
>
> Beyond that assessment, perceived road shock is primarily the axial
> component of vibration traveling to hen handlebars and this is less
> affected by steertube or even fork blade flex. I think this
> assessment of ride comfort is barking up the wrong tree, so to speak.

eh? is this the same famous jobst brandt that presumes that there is no
force associated with rim displacement of 0.003" - and that a rider
can't feel that force? the same famous jobst brandt that thinks bike
bearings are hydrodynamically separated? the jobst brandt that thinks
bearings can't true brinell? and you're now trying to tell us that you
can tell the difference between different materials in steer tubes, but
fork blade material doesn't count?

 

[Jay Beattie]

On Apr 19, 11:05 am, Dan O <[email protected]> wrote:
> On Apr 19, 6:48 am, Mike Rocket J Squirrel
>
>
>
>
>
> <[email protected]> wrote:
> > On 4/19/2008 6:31 AM Hobbes@spnb&s.com wrote:
>
> > > On Fri, 18 Apr 2008 13:58:51 -0800, agcou <[email protected]> wrote:
>
> > >> On Thu, 17 Apr 2008 19:55:23 -0400, Hobbes@spnb&s.com wrote:
>
> > >>> On Thu, 17 Apr 2008 15:23:53 -0700 (PDT), blackhead <[email protected]>
> > >>> wrote:
>
> > >>>> Are there any impartial tests that have been done on Auminium, Steel
> > >>>> and Carbon forks? Some people say carbon absorbs vibration better than
> > >>>> steel and Aluminium, others say it makes little difference... etc etc
> > >>> The differences of design, materials quality and manufacture are greater than
> > >>> the differences in the materials themselves.  Even in weight thereis an
> > >>> intersection between the three. I've got bikes with all three and they've all
> > >>> got something going for them.
>
> > >>> Really depends on what you're doing with the bike and which forks you're
> > >>> choosing from.
> > >> Did you read the OP's question?
>
> > > Yeah, there are no impartial tests that establish the relative characteristics
> > > of forks made from different materials. Such a test would have to holdall other
> > > variables constant in a way that simply isn't possible.
>
> > How come? Not arguing, just curious. Seems (to me, not a mechanical
> > engineer nor wrench) that one could get three forks with same geometry,
> > tilt at proper head tube angle, clamp dropouts to shaker table, add mass
> > loading from above, hang some accelerometers on the stem and let 'er rip..
> > Just to see, y'know?
>
> I've only ever ridden steel (and some of that plenty cheesy), but it
> seems to me the problem with this kind of test is that the chosen
> "geometry, tilt, load, etc." - not to mention thickness, etc. - might
> favor one material over another, and may or may not be suitable
> parameters for a given bike, rider, and purpose.  And then the matter
> of translating measured results into characteristics favorable for
> riding on... And then it also occurs to me that a shaker table is
> quite a different thing than a bicycle wheel.
>
> This kind of testing might be okay for a big manufacturer's R&D
> (although there goes "impartial" out the window if the marketing dept
> has any influence ;-), but for choosing what to ride on, the proof is
> (always) in the pudding.- Hide quoted text -
>

I have had steel, aluminum and CF forks all on the same 20+ year old
Cannondale frame. There was a suprisingly minor difference between
the original steel forks and the replacement 90's Kestrel CF (steel
steerer) -- except weight. Both were very stiff. I also had a pair
of aluminum forks on the bike for a short while. They were from a
later Cannondale 2.8 and were quite spongy climbing out of the
saddle. The 2.8 frame broke, and eventually I got a free replacement
frame with OEM carbon forks that were also stiffer than the original
aluminum forks . I have never found that carbon forks were magical in
terms of absorbing vibration. I have never owned a pair with a carbon
steerer, though, which may have additional magicality.-- Jay Beattie.

 

[Mike]

In article <[email protected]>, [email protected] says...
> On 18 Apr, 00:55, Hobbes@spnb&s.com wrote:
> > On Thu, 17 Apr 2008 15:23:53 -0700 (PDT), blackhead <[email protected]>
> > wrote:
> >
> > >Are there any impartial tests that have been done on Auminium, Steel
> > >and Carbon forks? Some people say carbon absorbs vibration better than
> > >steel and Aluminium, others say it makes little difference... etc etc
> >
> > The differences of design, materials quality and manufacture are greater than
> > the differences in the materials themselves.  Even in weight there isan
> > intersection between the three. I've got bikes with all three and they've all
> > got something going for them.
> >
> > Really depends on what you're doing with the bike and which forks you're
> > choosing from.
>
> So do Carbon forks really absorb vibration significantly better than
> Aluminium, so giving a better ride?
>
Hmmm, my carbon-forks (attached to a carbon frame road bike - tyres at 110-115psi) don't do a hell of a lot of
absorbing when I ride over the coarse chip road surface that our wonderful city council decided to plaster all over my
commuting route, whereas my aluminiun forks (attached to a full-suspension mountain bike - 120 mm front travel) does a
fine job of absorbing all the bumps induced by fist-sized cobbles on a fastdown-hill track. Can I make any conclusions
from this - only that the geometry, tyres, build and whatever is probably of far more significance.

To compare apples with apples, my CF road-bike is a lot lighter than th eold steel-frame, but I don't think there is a
_significant_ change in vibration absorption.

Mike

 

[Mike]

In article <[email protected]>, [email protected] says...
> [email protected] wrote:
> > On Apr 19, 10:18 am, Mike Rocket J Squirrel
> > Right. Three forks of the same make and model should be exactly the
> > same (although variance is likely to go up substantially at the bottom
> > end of the market), but you can't just test one carbon fork next to
> > one aluminum fork and say that the difference is the material.
>
> but previously you were saying there would be "vastly different results"
> - which of these conflicting statements would you have us believe?
>
This could be a result of wishful thinking of the form: " I spent vast amounts of hard-earned cash on these new forks,
so I had better be able to detect a vastly improved ride"...

Mike

 

[[email protected]]

On Apr 20, 3:10 pm, jim beam <[email protected]> wrote:
> Ben C wrote:
>
> <snip for clarity>
>
>
>
> > I would expect there to be much more likely to be non-negligible
> > differences between forks.
>
> of course. krygowski, being an intelligent, informed engineering
> professor with access to the correct instrumentation, already the owner
> of a cross-section of different forks, a sound knowledge of the
> principles, and with an open, inquiring mind, has already tested this
> position and is simply waiting for an opportunity to publish his
> results. or he's simply an idiot voicing underinformed opinion as fact
> and who has no inclination to actually test any damned thing that could
> possibly upset his comfy luddite little world.

False dichotomy, jim. One doesn't have to personally run tests and
publish results to recognize the ******** component of the advertising
hype that pops up in bike magazine ads and articles - things like
"rigid, yet compliant," "superfoods that increase healing power,"
"sealing gaps at the molecular level reduces friction at racing
speeds." Yes, and "incomparable, magic ride quality."

And a careful reader will note that I was simply giving my speculation
on what a fork comparison test would show. While I'd be willing to
bet with my friends on the issue, I wouldn't testify in court unless
I'd performed the proper test, or seen results I judged worthwhile.

Again, the worthwhile test would be a blind, on-road comparison test
using multiple riders, where the other factors were held constant.
It's the only way to filter out the placebo effect.

- Frank Krygowski

 

[[email protected]]

On Apr 20, 9:33 pm, Mike <[email protected]> wrote:
>
>
> Hmmm, my carbon-forks (attached to a carbon frame road bike - tyres at 110-115psi) don't do a hell of a lot of
> absorbing when I ride over the coarse chip road surface...

I have two good friends who have bought the Specialized carbon frames
& forks with the "Zerts" inserts. Both say the bikes are nice for
their lightness; but neither feels they can detect any particular
vibration absorption.

- Frank Krygowski

 

[jim beam]

[email protected] wrote:
> On Apr 20, 3:10 pm, jim beam <[email protected]> wrote:
>> Ben C wrote:
>>
>> <snip for clarity>
>>
>>
>>
>>> I would expect there to be much more likely to be non-negligible
>>> differences between forks.
>> of course. krygowski, being an intelligent, informed engineering
>> professor with access to the correct instrumentation, already the owner
>> of a cross-section of different forks, a sound knowledge of the
>> principles, and with an open, inquiring mind, has already tested this
>> position and is simply waiting for an opportunity to publish his
>> results. or he's simply an idiot voicing underinformed opinion as fact
>> and who has no inclination to actually test any damned thing that could
>> possibly upset his comfy luddite little world.
>
> False dichotomy, jim. One doesn't have to personally run tests and
> publish results to recognize the ******** component of the advertising
> hype

a highly scholarly approach to any technological problem. not.



> that pops up in bike magazine ads and articles - things like
> "rigid, yet compliant," "superfoods that increase healing power,"
> "sealing gaps at the molecular level reduces friction at racing
> speeds." Yes, and "incomparable, magic ride quality."
>
> And a careful reader will note that I was simply giving my speculation
> on what a fork comparison test would show. While I'd be willing to
> bet with my friends on the issue, I wouldn't testify in court unless
> I'd performed the proper test, or seen results I judged worthwhile.

so again, you're prepared to pronounce judgment on a subject with which
you have no experience.


>
> Again, the worthwhile test would be a blind, on-road comparison test
> using multiple riders, where the other factors were held constant.
> It's the only way to filter out the placebo effect.
>

you're a complete blathering idiot krygowski.