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Museeuw Flax Bicycle Frame Damping Characteristics

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bicycle_disciple

unread,
Aug 22, 2009, 1:54:44 PM8/22/09
to
Here's an interesting article from Frame Forum which shows the results
of a University of Ghent study on the vibration soaking
characteristics of a Museeuw Flax Frame (2010 model).
http://www.frameforum.org/newportal/preview-museeuw-2010.html

The article wrote towards the end :

" Each bike was fitted with five accelerometers at all the key points
of the bike that determine ride quality. From these sensors, the
collected data was then analysed to produce a map of how each bike
performed in terms of damping performance. When the four are stacked
up together, its clear from the graphs how well the Museeuw flax-based
frame stood up against the competition. In short, the subjective
claims of the many happy Museeuw owners (and those fortunate to have
ridden one in tests) are now backed-up with an objective set of
results confirming what they've known all along; the Museeuw is
undoubtedly one of the finest – if not the finest – performance
composite frame available today. "

There's also a picture of 3D amplitude vs frequency vs ride time plot
of 'vibration' in the frames tested. Any thoughts? This seems worth
discussing a bit. Jobst Brandt, do you have any opinions?

Also, more reading about flax as bike material here : http://tinyurl.com/ng82gz

BD

Lou Holtman

unread,
Aug 22, 2009, 2:20:47 PM8/22/09
to
bicycle_disciple schreef:

> Here's an interesting article from Frame Forum which shows the results
> of a University of Ghent study on the vibration soaking
> characteristics of a Museeuw Flax Frame (2010 model).
> http://www.frameforum.org/newportal/preview-museeuw-2010.html
>
> The article wrote towards the end :
>
> " Each bike was fitted with five accelerometers at all the key points
> of the bike that determine ride quality. From these sensors, the
> collected data was then analysed to produce a map of how each bike
> performed in terms of damping performance. When the four are stacked
> up together, its clear from the graphs how well the Museeuw flax-based
> frame stood up against the competition. In short, the subjective
> claims of the many happy Museeuw owners (and those fortunate to have
> ridden one in tests) are now backed-up with an objective set of
> results confirming what they've known all along; the Museeuw is
> undoubtedly one of the finest � if not the finest � performance

> composite frame available today. "
>
> There's also a picture of 3D amplitude vs frequency vs ride time plot
> of 'vibration' in the frames tested. Any thoughts? This seems worth
> discussing a bit. Jobst Brandt, do you have any opinions?
>
> Also, more reading about flax as bike material here : http://tinyurl.com/ng82gz
>
>
>
> BD


I cite:
`If you think of it in terms of a bell, the amplitude is the note and
the frequency is how long the bell holds that note before fading away�.


Next....

Lou

someone

unread,
Aug 22, 2009, 2:21:49 PM8/22/09
to
On Aug 22, 6:54 pm, bicycle_disciple <1.crazyboy.o...@gmail.com>
wrote:

> Here's an interesting article from Frame Forum which shows the results
> of a University of Ghent study on the vibration soaking
> characteristics of a Museeuw Flax Frame (2010 model).http://www.frameforum.org/newportal/preview-museeuw-2010.html

>
> The article wrote towards the end :
>
> " Each bike was fitted with five accelerometers at all the key points
> of the bike that determine ride quality.  From these sensors, the
> collected data was then analysed to produce a map of how each bike
> performed in terms of damping performance.  When the four are stacked
> up together, its clear from the graphs how well the Museeuw flax-based
> frame stood up against the competition. In short,  the subjective
> claims of  the many happy Museeuw owners (and those fortunate to have
> ridden one in tests) are now backed-up with an objective set of
> results confirming what they've known all along; the Museeuw is
> undoubtedly one of the finest – if not the finest – performance
> composite frame available today. "
>
> There's also a picture of 3D amplitude vs frequency vs ride time plot
> of 'vibration' in the frames tested. Any thoughts? This seems worth
> discussing a bit.  Jobst Brandt, do you have any opinions?


LOL Brandt, opinionated? You have not been paying attention.

B

unread,
Aug 22, 2009, 5:52:06 PM8/22/09
to
On Aug 22, 2:20 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> bicycle_disciple schreef:
>
>
>
> > Here's an interesting article from Frame Forum which shows the results
> > of a University of Ghent study on the vibration soaking
> > characteristics of a Museeuw Flax Frame (2010 model).
> >http://www.frameforum.org/newportal/preview-museeuw-2010.html
>
> > The article wrote towards the end :
>
> > " Each bike was fitted with five accelerometers at all the key points
> > of the bike that determine ride quality.  From these sensors, the
> > collected data was then analysed to produce a map of how each bike
> > performed in terms of damping performance.  When the four are stacked
> > up together, its clear from the graphs how well the Museeuw flax-based
> > frame stood up against the competition. In short,  the subjective
> > claims of  the many happy Museeuw owners (and those fortunate to have
> > ridden one in tests) are now backed-up with an objective set of
> > results confirming what they've known all along; the Museeuw is
> > undoubtedly one of the finest – if not the finest – performance

> > composite frame available today. "
>
> > There's also a picture of 3D amplitude vs frequency vs ride time plot
> > of 'vibration' in the frames tested. Any thoughts? This seems worth
> > discussing a bit.  Jobst Brandt, do you have any opinions?
>
> > Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
>
> > BD
>
> I cite:
> `If you think of it in terms of a bell, the amplitude is the note and
> the frequency is how long the bell holds that note before fading away´.
>
> Next....
>
> Lou

Lou :

That does look a little confusing to me as well. Note, atleast as I
knew it, is pitch represented by cycles/second which is frequency.
Amplitude is not the note. It is the magnitude of the cycle. The
reciprocal of frequency gives time length or period.


BD

Lou Holtman

unread,
Aug 22, 2009, 6:03:49 PM8/22/09
to
B schreef:

> On Aug 22, 2:20 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
>> bicycle_disciple schreef:
>>
>>
>>
>>> Here's an interesting article from Frame Forum which shows the results
>>> of a University of Ghent study on the vibration soaking
>>> characteristics of a Museeuw Flax Frame (2010 model).
>>> http://www.frameforum.org/newportal/preview-museeuw-2010.html
>>> The article wrote towards the end :
>>> " Each bike was fitted with five accelerometers at all the key points
>>> of the bike that determine ride quality. From these sensors, the
>>> collected data was then analysed to produce a map of how each bike
>>> performed in terms of damping performance. When the four are stacked
>>> up together, its clear from the graphs how well the Museeuw flax-based
>>> frame stood up against the competition. In short, the subjective
>>> claims of the many happy Museeuw owners (and those fortunate to have
>>> ridden one in tests) are now backed-up with an objective set of
>>> results confirming what they've known all along; the Museeuw is
>>> undoubtedly one of the finest � if not the finest � performance

>>> composite frame available today. "
>>> There's also a picture of 3D amplitude vs frequency vs ride time plot
>>> of 'vibration' in the frames tested. Any thoughts? This seems worth
>>> discussing a bit. Jobst Brandt, do you have any opinions?
>>> Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
>>> BD
>> I cite:
>> `If you think of it in terms of a bell, the amplitude is the note and
>> the frequency is how long the bell holds that note before fading away�.

>>
>> Next....
>>
>> Lou
>
> Lou :
>
> That does look a little confusing to me as well. Note, atleast as I
> knew it, is pitch represented by cycles/second which is frequency.
> Amplitude is not the note. It is the magnitude of the cycle. The
> reciprocal of frequency gives time length or period.
>
>
> BD


It is a pseudo scientific article with a lot of pseudo tech bla bla with
a lot of embarrassing errors. TOUR magazine tested a Museeuw frameset
some time ago. It was ridiculous expensive, no notable difference in
comfort but very well finished. That's it.

Lou

B

unread,
Aug 22, 2009, 6:34:35 PM8/22/09
to
On Aug 22, 6:03 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> B schreef:
>
>
>
> > On Aug 22, 2:20 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> >> bicycle_disciple schreef:
>
> >>> Here's an interesting article from Frame Forum which shows the results
> >>> of a University of Ghent study on the vibration soaking
> >>> characteristics of a Museeuw Flax Frame (2010 model).
> >>>http://www.frameforum.org/newportal/preview-museeuw-2010.html
> >>> The article wrote towards the end :
> >>> " Each bike was fitted with five accelerometers at all the key points
> >>> of the bike that determine ride quality.  From these sensors, the
> >>> collected data was then analysed to produce a map of how each bike
> >>> performed in terms of damping performance.  When the four are stacked
> >>> up together, its clear from the graphs how well the Museeuw flax-based
> >>> frame stood up against the competition. In short,  the subjective
> >>> claims of  the many happy Museeuw owners (and those fortunate to have
> >>> ridden one in tests) are now backed-up with an objective set of
> >>> results confirming what they've known all along; the Museeuw is
> >>> undoubtedly one of the finest – if not the finest – performance

> >>> composite frame available today. "
> >>> There's also a picture of 3D amplitude vs frequency vs ride time plot
> >>> of 'vibration' in the frames tested. Any thoughts? This seems worth
> >>> discussing a bit.  Jobst Brandt, do you have any opinions?
> >>> Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
> >>> BD
> >> I cite:
> >> `If you think of it in terms of a bell, the amplitude is the note and
> >> the frequency is how long the bell holds that note before fading away´.

>
> >> Next....
>
> >> Lou
>
> > Lou :
>
> > That does look a little confusing to me as well. Note, atleast as I
> > knew it, is pitch represented by cycles/second which is frequency.
> > Amplitude is not the note. It is the magnitude of the cycle. The
> > reciprocal of frequency gives time length or period.
>
> > BD
>
> It is a pseudo scientific article with a lot of pseudo tech bla bla with
> a lot of embarrassing errors. TOUR magazine tested a Museeuw frameset
> some time ago. It was ridiculous expensive, no notable difference in
> comfort but very well finished. That's it.
>
> Lou

Lou :

I'm not so much interested in the errors of the article save for the
information they passed out from the University of Ghent study.
Supposedly, Musseew signed a 5 year R&D deal with the University
(since he doesn't know much about engineering or design) to help
develop his bikes and that little graph they came out with showing
damping percentage is very interesting. I think it needs some
exploring to see whether those tiny %'s in difference between flax/cf
and just cf makes any real difference. Besides, the plots don't show
other types of bikes, such as bamboo, cf-al, titanium etc. One can't
definitely say that flax/cf bikes are the best in vibration dampening.

BD
http://cozybeehive.blogspot.com

Tim McNamara

unread,
Aug 22, 2009, 6:55:29 PM8/22/09
to
In article <4a90370a$1...@news4us.nl>,
Lou Holtman <lhollaatd...@planet.nl> wrote:

> bicycle_disciple schreef:
> > Here's an interesting article from Frame Forum which shows the
> > results of a University of Ghent study on the vibration soaking
> > characteristics of a Museeuw Flax Frame (2010 model).
> > http://www.frameforum.org/newportal/preview-museeuw-2010.html
> >
> > The article wrote towards the end :
> >
> > " Each bike was fitted with five accelerometers at all the key
> > points of the bike that determine ride quality. From these
> > sensors, the collected data was then analysed to produce a map of
> > how each bike performed in terms of damping performance. When the
> > four are stacked up together, its clear from the graphs how well
> > the Museeuw flax-based frame stood up against the competition. In
> > short, the subjective claims of the many happy Museeuw owners
> > (and those fortunate to have ridden one in tests) are now backed-up
> > with an objective set of results confirming what they've known all

> > along; the Museeuw is undoubtedly one of the finest � if not the
> > finest � performance composite frame available today. "


> >
> > There's also a picture of 3D amplitude vs frequency vs ride time
> > plot of 'vibration' in the frames tested. Any thoughts? This seems
> > worth discussing a bit. Jobst Brandt, do you have any opinions?
> >
> > Also, more reading about flax as bike material here :
> > http://tinyurl.com/ng82gz
>
>

> I cite: `If you think of it in terms of a bell, the amplitude is the
> note and the frequency is how long the bell holds that note before

> fading away�.
>
>
> Next....


Good grief. Thanks for saving me a waste of time reading the article.

z

unread,
Aug 22, 2009, 9:15:33 PM8/22/09
to
B wrote:
> On Aug 22, 6:03 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
>> B schreef:
>>
>>
>>
>>> On Aug 22, 2:20 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
>>>> bicycle_disciple schreef:
>>>>> Here's an interesting article from Frame Forum which shows the results
>>>>> of a University of Ghent study on the vibration soaking
>>>>> characteristics of a Museeuw Flax Frame (2010 model).
>>>>> http://www.frameforum.org/newportal/preview-museeuw-2010.html
>>>>> The article wrote towards the end :
>>>>> " Each bike was fitted with five accelerometers at all the key points
>>>>> of the bike that determine ride quality. From these sensors, the
>>>>> collected data was then analysed to produce a map of how each bike
>>>>> performed in terms of damping performance. When the four are stacked
>>>>> up together, its clear from the graphs how well the Museeuw flax-based
>>>>> frame stood up against the competition. In short, the subjective
>>>>> claims of the many happy Museeuw owners (and those fortunate to have
>>>>> ridden one in tests) are now backed-up with an objective set of
>>>>> results confirming what they've known all along; the Museeuw is
>>>>> undoubtedly one of the finest � if not the finest � performance

>>>>> composite frame available today. "
>>>>> There's also a picture of 3D amplitude vs frequency vs ride time plot
>>>>> of 'vibration' in the frames tested. Any thoughts? This seems worth
>>>>> discussing a bit. Jobst Brandt, do you have any opinions?
>>>>> Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
>>>>> BD
>>>> I cite:
>>>> `If you think of it in terms of a bell, the amplitude is the note and
>>>> the frequency is how long the bell holds that note before fading away�.

DAMPING. Does vibration change when wet?

B

unread,
Aug 22, 2009, 9:27:33 PM8/22/09
to
On Aug 22, 9:15 pm, z <N...@not.ca> wrote:
> B wrote:
> > On Aug 22, 6:03 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> >> B schreef:
>
> >>> On Aug 22, 2:20 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> >>>> bicycle_disciple schreef:
> >>>>> Here's an interesting article from Frame Forum which shows the results
> >>>>> of a University of Ghent study on the vibration soaking
> >>>>> characteristics of a Museeuw Flax Frame (2010 model).
> >>>>>http://www.frameforum.org/newportal/preview-museeuw-2010.html
> >>>>> The article wrote towards the end :
> >>>>> " Each bike was fitted with five accelerometers at all the key points
> >>>>> of the bike that determine ride quality.  From these sensors, the
> >>>>> collected data was then analysed to produce a map of how each bike
> >>>>> performed in terms of damping performance.  When the four are stacked
> >>>>> up together, its clear from the graphs how well the Museeuw flax-based
> >>>>> frame stood up against the competition. In short,  the subjective
> >>>>> claims of  the many happy Museeuw owners (and those fortunate to have
> >>>>> ridden one in tests) are now backed-up with an objective set of
> >>>>> results confirming what they've known all along; the Museeuw is
> >>>>> undoubtedly one of the finest – if not the finest – performance

> >>>>> composite frame available today. "
> >>>>> There's also a picture of 3D amplitude vs frequency vs ride time plot
> >>>>> of 'vibration' in the frames tested. Any thoughts? This seems worth
> >>>>> discussing a bit.  Jobst Brandt, do you have any opinions?
> >>>>> Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
> >>>>> BD
> >>>> I cite:
> >>>> `If you think of it in terms of a bell, the amplitude is the note and
> >>>> the frequency is how long the bell holds that note before fading away´.


Z wrote : "DAMPING. Does vibration change when wet?"

While trying to elicit mainly stupid responses, I should have thought
a few intelligent ones may squeeze their way in.

BD

bjwe...@gmail.com

unread,
Aug 22, 2009, 9:55:28 PM8/22/09
to
On Aug 22, 10:54 am, bicycle_disciple <1.crazyboy.o...@gmail.com>
wrote:

> Here's an interesting article from Frame Forum which shows the results
> of a University of Ghent study on the vibration soaking
> characteristics of a Museeuw Flax Frame (2010 model).http://www.frameforum.org/newportal/preview-museeuw-2010.html

>
> The article wrote towards the end :
>
> " Each bike was fitted with five accelerometers at all the key points
> of the bike that determine ride quality.  From these sensors, the
> collected data was then analysed to produce a map of how each bike
> performed in terms of damping performance.  When the four are stacked
> up together, its clear from the graphs how well the Museeuw flax-based
> frame stood up against the competition. In short,  the subjective
> claims of  the many happy Museeuw owners (and those fortunate to have
> ridden one in tests) are now backed-up with an objective set of
> results confirming what they've known all along; the Museeuw is
> undoubtedly one of the finest – if not the finest – performance
> composite frame available today. "
>
> There's also a picture of 3D amplitude vs frequency vs ride time plot
> of 'vibration' in the frames tested. Any thoughts? This seems worth
> discussing a bit.  Jobst Brandt, do you have any opinions?
>
> Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
>
> BD

They don't really give any information about what this
"3D amplitude vs frequency" graph captioned as
"Science Bit #2" is supposed to be showing, but it
seems to show that the advertised frame damps
something by about 0.7 percent while the other
frames damp that something by about 0.6 percent.
Well, color me impressed! It would have been useful
if they'd attached one of their accelerometers above the
seat padding and measured how much THAT damps.

Ben

Kerry Montgomery

unread,
Aug 22, 2009, 10:08:41 PM8/22/09
to

"b...@mambo.ucolick.org" <bjwe...@gmail.com> wrote in message
news:7975fc58-848d-465f...@y10g2000prf.googlegroups.com...

Ben

<end of earlier posts>
If the article doesn't do similar comparisons of other frame
characteristics, this is pretty useless. I think I could design a frame that
had much more damping than the Museeuw Flax frame, but it wouldn't be
something anyone would want to ride.
Kerry


Andre Jute

unread,
Aug 22, 2009, 10:17:39 PM8/22/09
to
On Aug 22, 6:54 pm, bicycle_disciple <1.crazyboy.o...@gmail.com>
wrote:
> Here's an interesting article from Frame Forum which shows the results
> of a University of Ghent study on the vibration soaking
> characteristics of a Museeuw Flax Frame (2010 model).http://www.frameforum.org/newportal/preview-museeuw-2010.html

>
> The article wrote towards the end :
>
> " Each bike was fitted with five accelerometers at all the key points
> of the bike that determine ride quality.  From these sensors, the
> collected data was then analysed to produce a map of how each bike
> performed in terms of damping performance.  When the four are stacked
> up together, its clear from the graphs how well the Museeuw flax-based
> frame stood up against the competition. In short,  the subjective
> claims of  the many happy Museeuw owners (and those fortunate to have
> ridden one in tests) are now backed-up with an objective set of
> results confirming what they've known all along; the Museeuw is
> undoubtedly one of the finest – if not the finest – performance
> composite frame available today. "
>
> There's also a picture of 3D amplitude vs frequency vs ride time plot
> of 'vibration' in the frames tested. Any thoughts? This seems worth
> discussing a bit.  Jobst Brandt, do you have any opinions?
>
> Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
>
> BD

Maybe you have the Flax Faith, Mr Disciple, but I don't put much chop
in the opinions of writer who puts himself forward as a technical
journalist and then confuses the meanings of frequency and amplitude.
Nor can I put too much faith in a bike designer, or his captive
university-based researchers when their graphs are so badly labelled
that I cannot make out what precisely is being damped where. All we
have here is a graphic claim that the non-flax frames damp aggregate
vibration (what sort? input where and how? damped where?)
approximately 15 per cent less than the flax frame. Even for popular
journalism, this is a significantly fact-free article. It would be
really useful, too, to have some comprehensible reference, say that
the same effect can be achieved by going up two tyre sizes (for a lot
less money...).

Andre Jute
Visit Jute on Amps at
http://www.audio-talk.co.uk/fiultra/
"wonderfully well written and reasoned information for the tube audio
constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site containing vital gems of
wisdom"
Stuart Perry Hi-Fi News & Record Review

someone

unread,
Aug 22, 2009, 10:52:56 PM8/22/09
to
On Aug 23, 2:15 am, z <N...@not.ca> wrote:
> B wrote:
> > On Aug 22, 6:03 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> >> B schreef:
>
> >>> On Aug 22, 2:20 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> >>>> bicycle_disciple schreef:
> >>>>> Here's an interesting article from Frame Forum which shows the results
> >>>>> of a University of Ghent study on the vibration soaking
> >>>>> characteristics of a Museeuw Flax Frame (2010 model).
> >>>>>http://www.frameforum.org/newportal/preview-museeuw-2010.html
> >>>>> The article wrote towards the end :
> >>>>> " Each bike was fitted with five accelerometers at all the key points
> >>>>> of the bike that determine ride quality.  From these sensors, the
> >>>>> collected data was then analysed to produce a map of how each bike
> >>>>> performed in terms of damping performance.  When the four are stacked
> >>>>> up together, its clear from the graphs how well the Museeuw flax-based
> >>>>> frame stood up against the competition. In short,  the subjective
> >>>>> claims of  the many happy Museeuw owners (and those fortunate to have
> >>>>> ridden one in tests) are now backed-up with an objective set of
> >>>>> results confirming what they've known all along; the Museeuw is
> >>>>> undoubtedly one of the finest – if not the finest – performance

> >>>>> composite frame available today. "
> >>>>> There's also a picture of 3D amplitude vs frequency vs ride time plot
> >>>>> of 'vibration' in the frames tested. Any thoughts? This seems worth
> >>>>> discussing a bit.  Jobst Brandt, do you have any opinions?
> >>>>> Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
> >>>>> BD
> >>>> I cite:
> >>>> `If you think of it in terms of a bell, the amplitude is the note and
> >>>> the frequency is how long the bell holds that note before fading away´.

Most certainly, if you dont seal your linen with varnish/dope the
cloth will become heavy and nullify the sky-hooks effect from ever
occuring with undertensioned member within the strain relationshi[ of
green crank compression when pedalling under extreme loading enough to
falsify marmite and celery jerkin in the Sunday following gresae my
nipple day.

I always find that dampness always lessens the buzz of a group ride.

someone

unread,
Aug 22, 2009, 10:55:43 PM8/22/09
to
On Aug 23, 3:08 am, "Kerry Montgomery" <kamon...@teleport.com> wrote:
> "b...@mambo.ucolick.org" <bjwei...@gmail.com> wrote in message

Gas pipe, anyone?

someone

unread,
Aug 22, 2009, 11:04:17 PM8/22/09
to

Put water in your tyres, that's a good damp(en)er.
I dont even see any claims about the weight of these framesets on
their website never mind anything to do with just about anything
else. It's all open to interpretation because there does not appear
to be any foundation. It's a marketing trick, schoolyard rumours.
The company cannot be held liable if they make no claims, the frameset
only has to be a bike frame, value $10.49 Nicely decorated.

Tim McNamara

unread,
Aug 22, 2009, 11:35:23 PM8/22/09
to
In article <WK0km.116310$9P.1...@newsfe08.iad>, z <No...@not.ca>
wrote:

> B wrote:
> > On Aug 22, 6:03 pm, Lou Holtman <lhollaatditmaar...@planet.nl>
> > wrote:
> >> B schreef:
> >>
> >>
> >>
> >>> On Aug 22, 2:20 pm, Lou Holtman <lhollaatditmaar...@planet.nl>
> >>> wrote:
> >>>> bicycle_disciple schreef:
> >>>>> Here's an interesting article from Frame Forum which shows the
> >>>>> results of a University of Ghent study on the vibration soaking
> >>>>> characteristics of a Museeuw Flax Frame (2010 model).
> >>>>> http://www.frameforum.org/newportal/preview-museeuw-2010.html
> >>>>> The article wrote towards the end : " Each bike was fitted with
> >>>>> five accelerometers at all the key points of the bike that
> >>>>> determine ride quality. From these sensors, the collected data
> >>>>> was then analysed to produce a map of how each bike performed
> >>>>> in terms of damping performance. When the four are stacked up
> >>>>> together, its clear from the graphs how well the Museeuw
> >>>>> flax-based frame stood up against the competition. In short,
> >>>>> the subjective claims of the many happy Museeuw owners (and
> >>>>> those fortunate to have ridden one in tests) are now backed-up
> >>>>> with an objective set of results confirming what they've known

> >>>>> all along; the Museeuw is undoubtedly one of the finest � if
> >>>>> not the finest � performance composite frame available today. "

> >>>>> There's also a picture of 3D amplitude vs frequency vs ride
> >>>>> time plot of 'vibration' in the frames tested. Any thoughts?
> >>>>> This seems worth discussing a bit. Jobst Brandt, do you have
> >>>>> any opinions? Also, more reading about flax as bike material
> >>>>> here
> >>>>> :http://tinyurl.com/ng82gz
> >>>>> BD
> >>>> I cite: `If you think of it in terms of a bell, the amplitude is
> >>>> the note and the frequency is how long the bell holds that note

> >>>> before fading away�. Next.... Lou


> >>> Lou : That does look a little confusing to me as well. Note,
> >>> atleast as I knew it, is pitch represented by cycles/second which
> >>> is frequency. Amplitude is not the note. It is the magnitude of
> >>> the cycle. The reciprocal of frequency gives time length or
> >>> period. BD
> >> It is a pseudo scientific article with a lot of pseudo tech bla
> >> bla with a lot of embarrassing errors. TOUR magazine tested a
> >> Museeuw frameset some time ago. It was ridiculous expensive, no
> >> notable difference in comfort but very well finished. That's it.
> >>
> >> Lou
> >
> > Lou :
> >
> > I'm not so much interested in the errors of the article save for
> > the information they passed out from the University of Ghent study.
> > Supposedly, Musseew signed a 5 year R&D deal with the University
> > (since he doesn't know much about engineering or design) to help
> > develop his bikes and that little graph they came out with showing
> > damping percentage is very interesting. I think it needs some
> > exploring to see whether those tiny %'s in difference between
> > flax/cf and just cf makes any real difference. Besides, the plots
> > don't show other types of bikes, such as bamboo, cf-al, titanium
> > etc. One can't definitely say that flax/cf bikes are the best in
> > vibration dampening.
> >
> > BD http://cozybeehive.blogspot.com
>
> DAMPING. Does vibration change when wet?

Family newsgroup, buddy.

Jobst Brandt

unread,
Aug 23, 2009, 12:26:59 AM8/23/09
to
some secretive person wrote;

> Here's an interesting article from Frame Forum which shows the
> results of a University of Ghent study on the vibration soaking

> characteristics of a Museeuw Flax Frame (2010 model):

http://www.frameforum.org/newportal/preview-museeuw-2010.html

> The article wrote toward the end :

# Each bike was fitted with five accelerometers at all the key points
# of the bike that determine ride quality. From these sensors, the
# collected data was then analysed to produce a map of how each bike
# performed in terms of damping performance. When the four are
# stacked up together, its clear from the graphs how well the Museeuw
# flax-based frame stood up against the competition. In short, the
# subjective claims of the many happy Museeuw owners (and those
# fortunate to have ridden one in tests) are now backed-up with an
# objective set of results confirming what they've known all along;
# the Museeuw is undoubtedly one of the finest – if not the finest –
# performance composite frame available today.

> There's also a picture of 3D amplitude vs frequency vs ride time
> plot of 'vibration' in the frames tested. Any thoughts? This seems
> worth discussing a bit. Jobst Brandt, do you have any opinions?

The article takes a long time to get to the subject, but then uses
classic similes and allusions to desirable characteristics, a few of
which directly conflict, like "rigid but vibration absorbent". All I
missed were the old saws of "suppleness and stiffness". Rings like a
bell alludes to audible response that has nothing to do with ride
quality, I suppose is manual vibration in handlebars or pedal
response, but that was not specified or maybe not measured.

> Also, more reading about flax as bike material here:

http://tinyurl.com/ng82gz

I can't take any more of this jive. It sounds a lot like how great
Tesla cars are, they having nothing new in electric propulsion except
a water cooled version of thousands of tiny camera batteries. This is
the Wankel all over again... a dead horse. The flax bicycle frame has
all the earmarks of a dud.

Keep flax fibers in linen cloth (sheets, shirts, and napkins) where it
earned its fame.

Jobst Brandt

B

unread,
Aug 23, 2009, 2:01:56 AM8/23/09
to
On Aug 22, 10:17 pm, Andre Jute <fiult...@yahoo.com> wrote:
> On Aug 22, 6:54 pm, bicycle_disciple <1.crazyboy.o...@gmail.com>
> wrote:
>
>
>
> > Here's an interesting article from Frame Forum which shows the results
> > of a University of Ghent study on the vibration soaking
> > characteristics of a Museeuw Flax Frame (2010 model).http://www.frameforum.org/newportal/preview-museeuw-2010.html
>
> > The article wrote towards the end :
>
> > " Each bike was fitted with five accelerometers at all the key points
> > of the bike that determine ride quality.  From these sensors, the
> > collected data was then analysed to produce a map of how each bike
> > performed in terms of damping performance.  When the four are stacked
> > up together, its clear from the graphs how well the Museeuw flax-based
> > frame stood up against the competition. In short,  the subjective
> > claims of  the many happy Museeuw owners (and those fortunate to have
> > ridden one in tests) are now backed-up with an objective set of
> > results confirming what they've known all along; the Museeuw is
> > undoubtedly one of the finest – if not the finest – performance
> > composite frame available today. "
>
> > There's also a picture of 3D amplitude vs frequency vs ride time plot
> > of 'vibration' in the frames tested. Any thoughts? This seems worth
> > discussing a bit.  Jobst Brandt, do you have any opinions?
>
> > Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
>
> > BD
Andre Jute wrote :

> Maybe you have the Flax Faith, Mr Disciple, but I don't put much chop
> in the opinions of writer who puts himself forward as a technical
> journalist and then confuses the meanings of frequency and amplitude.
> Nor can I put too much faith in a bike designer, or his captive
> university-based researchers when their graphs are so badly labelled
> that I cannot make out what precisely is being damped where. All we
> have here is a graphic claim that the non-flax frames damp aggregate
> vibration (what sort? input where and how? damped where?)
> approximately 15 per cent less than the flax frame. Even for popular
> journalism, this is a significantly fact-free article. It would be
> really useful, too, to have some comprehensible reference, say that
> the same effect can be achieved by going up two tyre sizes (for a lot
> less money...).

Dear Andre,

I'm looking at Flax bikes as objectively as you are. I did not confuse
the meaning of frequency and amplitude. I perfectly know what they
are, and one cannot use them alone to describe how a signal dampens
over time. The author of the frame forum article did get muddled a lot
and I wrote them an email asking them to correct it, else it would
stand out as embarrassing.

I do however stand by your statement that it is confusing to look at
the graph in the article and ascertain what "damping percentage" means
and how they arrived at it. %'s can be really tricky. Infact, a change
in small numbers can signify a big percentage. For instance, a change
of a system's value (any value) from 10 to 15 is a 50% change
increase. But if we look at the graph, particularly at this point :
(Frequency, Ride Time) = (3 Hz, 3000 seconds), the plot for the flax
bike seems to show a big hump in damping percentage that is infact
only 0.1 to 0.15% better than the other 3 frames. How do you put
something like that in perspective? So is that telling me that for
that much ride time (3000 secs = 0.8 hour), that bike is superior to
the rest but in the overall scheme of things, it is more or less
similar in vibration dampening? Not sure. The article did promise that
they would get their hands on more plots come Euro Bike, where Museeuw
would be holding some kind of press conference.


BD
http://cozybeehive.blogspot.com

Johnny Twelve-Point presented by JFT

unread,
Aug 23, 2009, 2:07:25 AM8/23/09
to
On 23 Aug 2009 04:26:59 GMT, Jobst Brandt <jbr...@sonic.net> wrote:

>The article takes a long time to get to the subject, but then uses
>classic similes and allusions to desirable characteristics,

I'm actually reminded of some of your comments about deep profile
wheels, though in that case you were using alllusions to posit that
they are extremely difficult to ride downhill or in brisk winds. I
think the phrase was only "marginally" better than disk wheels and
some reference to Tour de France riders not using disk wheels on the
front of bikes.

You never came out and said it, so perhaps you can clarify here: have
you ever ridden deep section wheels yourself?

B

unread,
Aug 23, 2009, 2:11:13 AM8/23/09
to

Dear Jobst,

You seem to think this has all the earmarks of a dud. I would have
passed by the bike and its marketing, only if weren't for the fact
that a well known University in Belgium and their Materials Science
department has been involved in the R&D. Yes, its a 5 year contract
and Museeuw is probably paying them to do these tests and what not,
but I still would think it very unprofessional on an engineering
institution's part to put a spin over things, just to get sales to
their customer. That said, I haven't seen anyone generate vibration
plots like this for any bike in the past. Everyone in the industry
talks about compliancy and vibration dampening, yet none give us any
objective data. This is the first time something like this happens,
which spurs an interest from my side.


BD
http://cozybeehive.blogspot.com

Ben C

unread,
Aug 23, 2009, 5:08:36 AM8/23/09
to
On 2009-08-23, Jobst Brandt <jbr...@sonic.net> wrote:
> some secretive person wrote;
>
>> Here's an interesting article from Frame Forum which shows the
>> results of a University of Ghent study on the vibration soaking
>> characteristics of a Museeuw Flax Frame (2010 model):
>
> http://www.frameforum.org/newportal/preview-museeuw-2010.html
>
>> The article wrote toward the end :
>
> # Each bike was fitted with five accelerometers at all the key points
> # of the bike that determine ride quality. From these sensors, the
> # collected data was then analysed to produce a map of how each bike
> # performed in terms of damping performance. When the four are
> # stacked up together, its clear from the graphs how well the Museeuw
> # flax-based frame stood up against the competition. In short, the
> # subjective claims of the many happy Museeuw owners (and those
> # fortunate to have ridden one in tests) are now backed-up with an
> # objective set of results confirming what they've known all along;
> # the Museeuw is undoubtedly one of the finest – if not the finest –
> # performance composite frame available today.
>
>> There's also a picture of 3D amplitude vs frequency vs ride time
>> plot of 'vibration' in the frames tested. Any thoughts? This seems
>> worth discussing a bit. Jobst Brandt, do you have any opinions?
>
> The article takes a long time to get to the subject, but then uses
> classic similes and allusions to desirable characteristics, a few of
> which directly conflict, like "rigid but vibration absorbent".

There's no conflict there-- "vibration absorbency" refers to damping not
to stiffness.

Try hitting a cricket ball with a cricket bat and then with a frying
pan. The bat is stiffer but better damped.

This new bike is meant to be more like a cricket bat than a frying pan.

Chalo

unread,
Aug 23, 2009, 5:19:49 AM8/23/09
to
Ben C wrote:

>
> Jobst Brandt wrote:
> >
> > The article takes a long time to get to the subject, but then uses
> > classic similes and allusions to desirable characteristics, a few of
> > which directly conflict, like "rigid but vibration absorbent".
>
> There's no conflict there-- "vibration absorbency" refers to damping not
> to stiffness.
>
> Try hitting a cricket ball with a cricket bat and then with a frying
> pan. The bat is stiffer but better damped.
>
> This new bike is meant to be more like a cricket bat than a frying pan.

It's actually more like a wooden bat versus a metal bat. In baseball,
metal bats actually work very well and would be indispensable in
professional leagues if they were permitted.

But does this difference even matter if there is an airbag between the
ball and whatever you're hitting it with?

Does it matter if one bat or the other breaks and injures you in the
process?

Chalo

Ben C

unread,
Aug 23, 2009, 5:29:47 AM8/23/09
to
On 2009-08-23, Chalo <chalo....@gmail.com> wrote:
> Ben C wrote:
>>
>> Jobst Brandt wrote:
>> >
>> > The article takes a long time to get to the subject, but then uses
>> > classic similes and allusions to desirable characteristics, a few of
>> > which directly conflict, like "rigid but vibration absorbent".
>>
>> There's no conflict there-- "vibration absorbency" refers to damping not
>> to stiffness.
>>
>> Try hitting a cricket ball with a cricket bat and then with a frying
>> pan. The bat is stiffer but better damped.
>>
>> This new bike is meant to be more like a cricket bat than a frying pan.
>
> It's actually more like a wooden bat versus a metal bat. In baseball,
> metal bats actually work very well and would be indispensable in
> professional leagues if they were permitted.

Right, although I'm not sure which is stiffer: the wooden or metal bat.

> But does this difference even matter if there is an airbag between the
> ball and whatever you're hitting it with?

I don't know. Would have to ride the bike. I was just pointing out that
rigid but better damped does at least make sense in principle.

> Does it matter if one bat or the other breaks and injures you in the
> process?

Of course, but there's no reason to think this flax bike is weaker
than a regular CF one.

The flax fibres probably aren't as strong, but they maybe use more of
them or something, or have as much CF in there too as they would anyway.

spins

unread,
Aug 23, 2009, 7:53:20 AM8/23/09
to

I graduated there. IT IS A DUMP.

someone

unread,
Aug 23, 2009, 8:03:38 AM8/23/09
to
On 23 Aug, 10:08, Ben C <spams...@spam.eggs> wrote:

Cricket bat handles which are wrapped in line (so bear a similarity)
before fitting a rubber sleeve are not 3000 euros. I'm not declaring
there is no benefit, simply that the minimal change there is, is being
sold at an elevated price.

someone

unread,
Aug 23, 2009, 8:14:31 AM8/23/09
to
On 23 Aug, 10:29, Ben C <spams...@spam.eggs> wrote:

Flax fibre will likely improve the failure mode of a composite frame
so is does not splinter when overstressed. I dont think carbon fibre
frames should be constructed with only one fibre length. There should
be a combination of fibre length so as to avoid fragmentation into
shards upon fracture. I think for the possible safety benefits, a
flax/carbon mix will be more popular with professionals. Weights of
frames are low enough that encasement of a carbon frame is viable.

Lou Holtman

unread,
Aug 23, 2009, 8:29:25 AM8/23/09
to
B schreef:

> On Aug 23, 12:26 am, Jobst Brandt <jbra...@sonic.net> wrote:
>> some secretive person wrote;
>>
>>> Here's an interesting article from Frame Forum which shows the
>>> results of a University of Ghent study on the vibration soaking
>>> characteristics of a Museeuw Flax Frame (2010 model):
>> http://www.frameforum.org/newportal/preview-museeuw-2010.html
>>
>>> The article wrote toward the end :
>> # Each bike was fitted with five accelerometers at all the key points
>> # of the bike that determine ride quality. From these sensors, the
>> # collected data was then analysed to produce a map of how each bike
>> # performed in terms of damping performance. When the four are
>> # stacked up together, its clear from the graphs how well the Museeuw
>> # flax-based frame stood up against the competition. In short, the
>> # subjective claims of the many happy Museeuw owners (and those
>> # fortunate to have ridden one in tests) are now backed-up with an
>> # objective set of results confirming what they've known all along;
>> # the Museeuw is undoubtedly one of the finest � if not the finest �


No it is not the first time this sort of tests are done. I read a couple
and all the time the results were too embarrassing to publish widely.
The test is really simple. You want the dampening of a material compared
with another material take a tube of that material and measure the
frequency response and compare it with frequency response of a tube with
the same dimensions made of a different material. You don't take a whole
bike and then say something about the material the frame was made off.
That is sloppy research.

Lou

Tim McNamara

unread,
Aug 23, 2009, 12:41:56 PM8/23/09
to
In article
<84140db7-d414-47e9...@24g2000yqm.googlegroups.com>,
B <1.crazy...@gmail.com> wrote:

> You seem to think this has all the earmarks of a dud. I would have
> passed by the bike and its marketing, only if weren't for the fact
> that a well known University in Belgium and their Materials Science
> department has been involved in the R&D. Yes, its a 5 year contract
> and Museeuw is probably paying them to do these tests and what not,
> but I still would think it very unprofessional on an engineering
> institution's part to put a spin over things, just to get sales to
> their customer.

This is SOP in university research these days. Whomever is paying for
the research gets the results they want. Research is marketing, and a
university which doesn't play ball doesn't get grants.

Jobst Brandt

unread,
Aug 23, 2009, 1:13:48 PM8/23/09
to
Ben C? mysterious wrote:

http://www.frameforum.org/newportal/preview-museeuw-2010.html

Your example is a non sequitur. Try a wooden cricket bat and a rubber
one and you'll be closer. Don't compare frying pans with bicycle
frames either. A rider does not feel acoustic resonances in
handlebars of a bicycle that are usually absent because the bars are
wrapped with tape, flax or otherwise. However, vibrations enter the
bicycle through pneumatic tires that don't transmit sharp step
functions or acoustic noise, although this is often put forth as the
basis of ride quality. That is mainly resonances of highly inflated
lightweight tire casings.

Jobst Brandt

Ben C

unread,
Aug 23, 2009, 1:31:25 PM8/23/09
to
On 2009-08-23, Tim McNamara <tim...@bitstream.net> wrote:
> In article
><84140db7-d414-47e9...@24g2000yqm.googlegroups.com>,
> B <1.crazy...@gmail.com> wrote:
>
>> You seem to think this has all the earmarks of a dud. I would have
>> passed by the bike and its marketing, only if weren't for the fact
>> that a well known University in Belgium and their Materials Science
>> department has been involved in the R&D. Yes, its a 5 year contract
>> and Museeuw is probably paying them to do these tests and what not,
>> but I still would think it very unprofessional on an engineering
>> institution's part to put a spin over things, just to get sales to
>> their customer.
>
> This is SOP in university research these days. Whomever is paying for
> the research gets the results they want.

Whoever.

Ben C

unread,
Aug 23, 2009, 1:38:30 PM8/23/09
to
On 2009-08-23, Jobst Brandt <jbr...@sonic.net> wrote:

No it isn't.

> Try a wooden cricket bat and a rubber one and you'll be closer.

A rubber cricket bat resembles a dead horse or a herring more than it
does a metal bicycle frame.

> Don't compare frying pans with bicycle frames either. A rider does
> not feel acoustic resonances in handlebars of a bicycle that are
> usually absent because the bars are wrapped with tape, flax or
> otherwise.

That may be true. I was just clarifying what's meant "rigid but
vibration absorbent"-- it's a perfectly intelligible idea, even if it
doesn't matter.

Anyway, vibration absorbency is even lower on the agenda for frying
pans.

B

unread,
Aug 23, 2009, 1:47:49 PM8/23/09
to
On Aug 23, 12:41 pm, Tim McNamara <tim...@bitstream.net> wrote:
> In article
> <84140db7-d414-47e9-b8d3-7cc67ad15...@24g2000yqm.googlegroups.com>,

Tim,

I certainly don't know that.It may happen, it may not. I think its not
right to generalize that to all institutions and reduce their work to
just some cleverly crafted hogwash.


BD

Tom Sherman °_°

unread,
Aug 23, 2009, 1:59:24 PM8/23/09
to
Ben C? wrote:
> [...]

> A rubber cricket bat resembles a dead horse or a herring more than it
> does a metal bicycle frame.[...]

And is about as useful for cutting down the mightiest tree in the forest.

--
Tom Sherman - 42.435731,-83.985007
Celebrity culture is an opposite of community, informing us
that these few nonsense-heads matter but that the rest of
us do not. - Jay Griffiths

Ron

unread,
Aug 23, 2009, 2:03:53 PM8/23/09
to

Dear Someone,

After a little bit of research, I found out that the patented process
by which these bikes are made are similar to those used in the
cigarette making industry. http://www.patentstorm.us/patents/6584981/description.html.
The frame is a bunch of tubes combining both carbon with fiber,
produced by a patented high temperature and pressure process, and
these tubes are bonded to form a frame using a special purpose glue.


BD
http://cozybeehive.blogspot.com

Michael Press

unread,
Aug 23, 2009, 3:12:19 PM8/23/09
to
In article <oeadnY1QH7cxOQ3X...@earthlink.com>,
"Kerry Montgomery" <kamo...@teleport.com> wrote:


Outlook Express sometimes fails to quote text,
as it did with your message. I removed all quoted
text so as not to transmit the confusing set of
attributions and quotes. Please read your own
article to see where your news reader failed to
quote with a `>' character in the first column.

--
Michael Press

Michael Press

unread,
Aug 23, 2009, 3:18:31 PM8/23/09
to
In article <slrnh921k4....@bowser.marioworld>,
Ben C <spam...@spam.eggs> wrote:

> Try hitting a cricket ball with a cricket bat and then with a frying
> pan. The bat is stiffer but better damped.

A cast iron frying pan?

--
Michael Press

Michael Press

unread,
Aug 23, 2009, 3:20:59 PM8/23/09
to
In article <slrnh922rr....@bowser.marioworld>,
Ben C <spam...@spam.eggs> wrote:

> On 2009-08-23, Chalo <chalo....@gmail.com> wrote:
> > Ben C wrote:
> >>
> >> Jobst Brandt wrote:
> >> >
> >> > The article takes a long time to get to the subject, but then uses
> >> > classic similes and allusions to desirable characteristics, a few of
> >> > which directly conflict, like "rigid but vibration absorbent".
> >>
> >> There's no conflict there-- "vibration absorbency" refers to damping not
> >> to stiffness.
> >>
> >> Try hitting a cricket ball with a cricket bat and then with a frying
> >> pan. The bat is stiffer but better damped.
> >>
> >> This new bike is meant to be more like a cricket bat than a frying pan.
> >
> > It's actually more like a wooden bat versus a metal bat. In baseball,
> > metal bats actually work very well and would be indispensable in
> > professional leagues if they were permitted.
>
> Right, although I'm not sure which is stiffer: the wooden or metal bat.
>
> > But does this difference even matter if there is an airbag between the
> > ball and whatever you're hitting it with?
>
> I don't know. Would have to ride the bike. I was just pointing out that
> rigid but better damped does at least make sense in principle.

What is to be damped
that is not already damped in the tires and saddle?

--
Michael Press

carl...@comcast.net

unread,
Aug 23, 2009, 3:55:55 PM8/23/09
to
On Sat, 22 Aug 2009 10:54:44 -0700 (PDT), bicycle_disciple
<1.crazy...@gmail.com> wrote:

>Here's an interesting article from Frame Forum which shows the results
>of a University of Ghent study on the vibration soaking

>characteristics of a Museeuw Flax Frame (2010 model).
>http://www.frameforum.org/newportal/preview-museeuw-2010.html
>
>The article wrote towards the end :


>
>" Each bike was fitted with five accelerometers at all the key points

>of the bike that determine ride quality. From these sensors, the

>collected data was then analysed to produce a map of how each bike

>performed in terms of damping performance. When the four are stacked
>up together, its clear from the graphs how well the Museeuw flax-based
>frame stood up against the competition. In short, the subjective
>claims of the many happy Museeuw owners (and those fortunate to have
>ridden one in tests) are now backed-up with an objective set of
>results confirming what they've known all along; the Museeuw is
>undoubtedly one of the finest � if not the finest � performance


>composite frame available today. "
>
>There's also a picture of 3D amplitude vs frequency vs ride time plot
>of 'vibration' in the frames tested. Any thoughts? This seems worth
>discussing a bit. Jobst Brandt, do you have any opinions?
>

>Also, more reading about flax as bike material here : http://tinyurl.com/ng82gz
>
>
>

>BD

Dear BD,

Find a beautifully smooth road where you don't notice any vibration.

Ride a long, smooth, straight stretch while holding a digital camera
in video mode.

Switch between resting your camera hand on the handlebar, where the
frame vibration affects things, and holding the camera up in the air,
where your body damps the vibration.

The sensitive camera will show a dramatic difference, not just in the
video shaking, but also in the sound level.

But it's still a beautifully smooth road.

Cheers,

Carl Fogel

Bill Sornson

unread,
Aug 23, 2009, 4:41:18 PM8/23/09
to
Michael Press wrote:
> In article <oeadnY1QH7cxOQ3X...@earthlink.com>,
> "Kerry Montgomery" <kamo...@teleport.com> wrote:
>
>
> Outlook Express sometimes fails to quote text,
> as it did with your message.

Kerry's post had fully quoted text on my newsreader, and I use OE.

> I removed all quoted
> text so as not to transmit the confusing set of
> attributions and quotes. Please read your own
> article to see where your news reader failed to
> quote with a `>' character in the first column.

My you're helpful. You could work for the nanny state.

BS


Jobst Brandt

unread,
Aug 23, 2009, 4:41:43 PM8/23/09
to
Carl Fogel wrote:

>> Here's an interesting article from Frame Forum which shows the
>> results of a University of Ghent study on the vibration soaking
>> characteristics of a Museeuw Flax Frame (2010 model).

http://www.frameforum.org/newportal/preview-museeuw-2010.html

>> The article wrote towards the end:

# Each bike was fitted with five accelerometers at all the key points
# of the bike that determine ride quality. From these sensors, the
# collected data was then analysed to produce a map of how each bike
# performed in terms of damping performance. When the four are
# stacked up together, its clear from the graphs how well the Museeuw
# flax-based frame stood up against the competition. In short, the
# subjective claims of the many happy Museeuw owners (and those
# fortunate to have ridden one in tests) are now backed-up with an
# objective set of results confirming what they've known all along;
# the Museeuw is undoubtedly one of the finest - if not the finest -
# performance composite frame available today.



>> There's also a picture of 3D amplitude vs frequency vs ride time
>> plot of 'vibration' in the frames tested. Any thoughts? This seems
>> worth discussing a bit. Jobst Brandt, do you have any opinions?

>> Also, more reading about flax as bike material here:

http://tinyurl.com/ng82gz

> Find a beautifully smooth road where you don't notice any vibration.

> Ride a long, smooth, straight stretch while holding a digital camera
> in video mode.

> Switch between resting your camera hand on the handlebar, where the
> frame vibration affects things, and holding the camera up in the
> air, where your body damps the vibration.

> The sensitive camera will show a dramatic difference, not just in
> the video shaking, but also in the sound level.

> But it's still a beautifully smooth road.

Performing this test on a steel frame and a flax frame bicycle, using
the same wheels, is a more valid comparison. Shake seen in a camera
does not represent what a bicyclist considers am uncomfortable ride.

Jobst Brandt

B

unread,
Aug 23, 2009, 4:54:23 PM8/23/09
to

Dear Carl,

What are you suggesting? Are you saying that a camera mounted on your
helmet is better than a camera mounted on the seattube or the
handlebar? It doesn't make sense. Humans and cameras vary. A fat human
probably has more body dampening than a thin one as it has to go
through all those layers of fat. Similarly, a camera designed with
special circuits can take films while filtering out vibration to a
decent amount. Both aren't objective ways to analyze the dampening
characteristics of a bicycle frame.

I article I linked to and quoted from (the University of Ghent study)
is also sketchy. How can you measure frame energy absorption with just
5 accelerometers? The article also does not point out who rode the
bikes, where they rode it, the techniques they used to excite the
bike, whether it was correctly loaded etc. That said, the plot is
still interesting to discuss.

BD
http://cozybeehive.blogspot.com

Lou Holtman

unread,
Aug 23, 2009, 5:06:03 PM8/23/09
to
B schreef:

> On Aug 23, 3:55 pm, carlfo...@comcast.net wrote:
>> On Sat, 22 Aug 2009 10:54:44 -0700 (PDT), bicycle_disciple
>>
>>
>>
>> <1.crazyboy.o...@gmail.com> wrote:
>>> Here's an interesting article from Frame Forum which shows the results
>>> of a University of Ghent study on the vibration soaking
>>> characteristics of a Museeuw Flax Frame (2010 model).
>>> http://www.frameforum.org/newportal/preview-museeuw-2010.html
>>> The article wrote towards the end :
>>> " Each bike was fitted with five accelerometers at all the key points
>>> of the bike that determine ride quality. From these sensors, the
>>> collected data was then analysed to produce a map of how each bike
>>> performed in terms of damping performance. When the four are stacked
>>> up together, its clear from the graphs how well the Museeuw flax-based
>>> frame stood up against the competition. In short, the subjective
>>> claims of the many happy Museeuw owners (and those fortunate to have
>>> ridden one in tests) are now backed-up with an objective set of
>>> results confirming what they've known all along; the Museeuw is
>>> undoubtedly one of the finest � if not the finest � performance

I just reread the test in TOUR magazine of the Museeuw MF 5 frameset.
The frame was not very torsional stiff and the bike came with a one
piece handlebar stem also made out of that flax fiber stuff. Frameset
cost 3550 euro......

Lou

carl...@comcast.net

unread,
Aug 23, 2009, 5:20:15 PM8/23/09
to

Dear BD,

Okay, try simpler experiments.

See if you notice the difference in damping between the same bicycle
with and without a 16-ounce bottle of water attached to the frame.

Or see if you notice the difference between the same bicycle before
and after you tap the presta valves with a finger--pfffft!--and reduce
the pressure about half of one psi.

You'll have about as much luck doing that as you will noticing a 0.5%
difference in frame damping by watching how much a video shakes off a
handlebar at 20 mph.

Using five accelerometers to detect damping differences of less than
half one one per cent--and making a wild fuss about the
results--suggests that someone lost sight of the scale.

Cheers,

Carl Fogel

B

unread,
Aug 23, 2009, 5:52:13 PM8/23/09
to
On Aug 23, 5:06 pm, Lou Holtman <lhollaatditmaar...@planet.nl> wrote:
> B schreef:
>
>
>
> > On Aug 23, 3:55 pm, carlfo...@comcast.net wrote:
> >> On Sat, 22 Aug 2009 10:54:44 -0700 (PDT), bicycle_disciple
>
> >> <1.crazyboy.o...@gmail.com> wrote:
> >>> Here's an interesting article from Frame Forum which shows the results
> >>> of a University of Ghent study on the vibration soaking
> >>> characteristics of a Museeuw Flax Frame (2010 model).
> >>>http://www.frameforum.org/newportal/preview-museeuw-2010.html
> >>> The article wrote towards the end :
> >>> " Each bike was fitted with five accelerometers at all the key points
> >>> of the bike that determine ride quality.  From these sensors, the
> >>> collected data was then analysed to produce a map of how each bike
> >>> performed in terms of damping performance.  When the four are stacked
> >>> up together, its clear from the graphs how well the Museeuw flax-based
> >>> frame stood up against the competition. In short,  the subjective
> >>> claims of  the many happy Museeuw owners (and those fortunate to have
> >>> ridden one in tests) are now backed-up with an objective set of
> >>> results confirming what they've known all along; the Museeuw is
> >>> undoubtedly one of the finest – if not the finest – performance

Dear Lou,

It seems you are right. I too did some digging to literature from Tour
Mag. The torsional stiffness of the headtube ("Lenkkopfsteifigkeit")
for a Museeuw Flax Bike Model MF-5 (the bike shown in the 3D plot from
the U of Ghent study) was 68 Nm/degree and bottom bracket stiffness
("Tretlagersteifigkeit") was 44 N/mm. Let's put that in perspective.
Early this year, the same independent magazine tested 27 top end
carbon fiber bikes that you can buy for money. From the published test
results, I calculated that the average torsional stiffness for those
27 bikes was on the order 95.85 Nm/degree and the average bottom
bracket stiffness was 55.77 N/mm. So the flax bike appears to be 29%
lower in torsional stiffness and 21.10% lower in bottom bracket
stiffness. This isn't sensational. But since the Flax bike doesn't not
claim to be superior in stiffness but does claim to be superior in
vibration dampening, my results prompt me to question whether the
vibration dampening is simply because the bike is made to be more
complaint than its stiffer cousins. Does flax have anything at all to
do with vibration dampening? The 3D graph certainly shows tiny
percentages of different and I argue those minute figures may hardly
be perceptible to a rider.

BD
http://cozybeehive.blogspot.com

B

unread,
Aug 23, 2009, 6:11:14 PM8/23/09
to

Carl,

Ahhh, I see where you're going with this. One way to get out of the
trap of capturing the effects of a tire in a study like this is to
test the frameset alone. Load it on a shaking table attached via
dropouts, simulate some frequencies seen in real life (such as the
cobbles of Paris-Roubaix) and lets see what the results show from one
frame to the next.

BD
http://cozybeehive.blogspot.com

B

unread,
Aug 23, 2009, 6:13:07 PM8/23/09
to

Ahhh, I see where you're going with this. One way to get out of the

bjwe...@gmail.com

unread,
Aug 23, 2009, 7:12:27 PM8/23/09
to

Stop engaging in wishful thinking.

Capturing the effects of a tire in a study of vibration
damping is not a drawback. It is a necessity, because
hardly anyone rides a bicycle without tires.

The test you propose of a bare frame on a table
would be illegitimate because the input spectrum
of vibrations to the frame in any real life use is modified
by the tires, the response is modified by the fact that
the frame is loaded by the rider's weight, and so on.

It's all wishful thinking. Compared to the soft stuff
in the system - tires, seats, handlebar tape, arms
and legs - frames are so much more stiff that there
is no point in measuring the vibration differences
between frames and claiming it means something.
Variations in frame geometry are probably more
important (slacker head angle for rougher surfaces, etc).
I have no doubt that someone at this university measured
vibrations in frames. The error is in assuming that
the measurement shows something meaningful.

Ben

B

unread,
Aug 23, 2009, 7:42:58 PM8/23/09
to
On Aug 23, 7:12 pm, "b...@mambo.ucolick.org" <bjwei...@gmail.com>

Ben,

I engaged in wishful thinking only to eliminate the effects of tire
and tube on frame dampening. In reality, you're right, bikes are
ridden with wheels on and they above all see the major impacts of road
surface irregularities. Note that wheels are not the only dynamic
components. Cranks, chainrings and chains are too. It would be hard to
believe that they have zero effect on vibration. Think about a sprint
cyclist running at a top 100-120 RPM and shifting gears along with it.
It would be interested to see if U of Ghent studied the effects these
could have on vibration.

BD
http://cozybeehive.blogspot.com

Jobst Brandt

unread,
Aug 23, 2009, 8:24:41 PM8/23/09
to
All this talk of vibration damping seems to be misdirected, because
bicyclists have as a whole, not complained about vibration in the
amplitudes that the structure transmits. For bumpy surfaces spring
suspension frames have been designed. Throughout the history of
bicycling, the functions of structural integrity and shock absorption
have been separate as they are in all vehicles, be they cars, trucks,
railways, prams, bicycles, and motorcycles.

These vehicles have structurally rigid elements that for shock
absorption have been equipped with hinges with links supported by
springs. No reasonable designer combines the two functions that are
anathema to each other. Yet people unclear on the concept continue
claim to have merged springs with structures using "space age
materials". I can think of a good subject for these folks. They
should focus on making a pogo stick in which the shaft is the
elastomer and leave bicycles alone.

Jobst Brandt

Andre Jute

unread,
Aug 23, 2009, 11:58:41 PM8/23/09
to
On Aug 23, 7:01 am, B <1.crazyboy.o...@gmail.com> wrote:
> On Aug 22, 10:17 pm, Andre Jute <fiult...@yahoo.com> wrote:
>
>
>
> > On Aug 22, 6:54 pm, bicycle_disciple <1.crazyboy.o...@gmail.com>

> > wrote:
>
> > > Here's an interesting article from Frame Forum which shows the results
> > > of a University of Ghent study on the vibration soaking
> > > characteristics of a Museeuw Flax Frame (2010 model).http://www.frameforum.org/newportal/preview-museeuw-2010.html

>
> > > The article wrote towards the end :
>
> > > " Each bike was fitted with five accelerometers at all the key points
> > > of the bike that determine ride quality.  From these sensors, the
> > > collected data was then analysed to produce a map of how each bike
> > > performed in terms of damping performance.  When the four are stacked
> > > up together, its clear from the graphs how well the Museeuw flax-based
> > > frame stood up against the competition. In short,  the subjective
> > > claims of  the many happy Museeuw owners (and those fortunate to have
> > > ridden one in tests) are now backed-up with an objective set of
> > > results confirming what they've known all along; the Museeuw is
> > > undoubtedly one of the finest – if not the finest – performance
> > > composite frame available today. "
>
> > > There's also a picture of 3D amplitude vs frequency vs ride time plot
> > > of 'vibration' in the frames tested. Any thoughts? This seems worth
> > > discussing a bit.  Jobst Brandt, do you have any opinions?
>
> > > Also, more reading about flax as bike material here :http://tinyurl.com/ng82gz
>
> > > BD
>
>  Andre Jute wrote :
>
> > Maybe you have the Flax Faith, Mr Disciple, but I don't put much chop
> > in the opinions of writer who puts himself forward as a technical
> > journalist and then confuses the meanings of frequency and amplitude.
> > Nor can I put too much faith in a bike designer, or his captive
> > university-based researchers when their graphs are so badly labelled
> > that I cannot make out what precisely is being damped where. All we
> > have here is a graphic claim that the non-flax frames damp aggregate
> > vibration (what sort? input where and how? damped where?)
> > approximately 15 per cent less than the flax frame. Even for popular
> > journalism, this is a significantly fact-free article. It would be
> > really useful, too, to have some comprehensible reference, say that
> > the same effect can be achieved by going up two tyre sizes (for a lot
> > less money...).
>
> Dear Andre,
>
> I'm looking at Flax bikes as objectively as you are. I did not confuse
> the meaning of frequency and amplitude. I perfectly know what they
> are, and one cannot use them alone to describe how a signal dampens
> over time. The author of the frame forum article did get muddled a lot
> and I wrote them an email asking them to correct it, else it would
> stand out as embarrassing.
>
> I do however stand by your statement that it is confusing to look at
> the graph in the article and ascertain what "damping percentage" means
> and how they arrived at it. %'s can be really tricky. Infact, a change
> in small numbers can signify a big percentage. For instance, a change
> of a system's value (any value) from 10 to 15 is a 50% change
> increase. But if we look at the graph, particularly at this point :
> (Frequency, Ride Time) = (3 Hz, 3000 seconds), the plot for the flax
> bike seems to show a big hump in damping percentage that is infact
> only 0.1 to 0.15% better than the other 3 frames. How do you put
> something like that in perspective? So is that telling me that for
> that much ride time (3000 secs = 0.8 hour), that bike is superior to
> the rest but in the overall scheme of things, it is more or less
> similar in vibration dampening? Not sure. The article did promise that
> they would get their hands on more plots come Euro Bike, where Museeuw
> would be holding some kind of press conference.
>
> BDhttp://cozybeehive.blogspot.com

As I said to the pedalpals today when they somewhat over-effusively
congratulated me on the perfection of my arrangements for our Tour of
Ireland outing (I was asleep until they came to pull me out of bed),
"Kiss the ring." You see, I was right, the article is rubbish but the
graph is seriously misleading, because I got fifteen per cent from it,
whereas you get 0.15 per cent. If that graph was in addition scaled in
inverse log, I would without a moment's hesitation have accused its
makers of deliberate and probably mercenary malice rather than
carelessness or ignorance. (Don't even ask how I know such tricks of
the statistical trades!)

Apologies for my tone in the first message. I read and admire your
netsite, especially the speculative slant of it, which I miss from the
pretend-engineers here on RBT, some of whom are positively proud of
not having a shred of humour -- or originality, or brains for that
matter. I thought I was writing to one of these wankers. An
embarrassing mistake: I blush.

Andre Jute
Pedontologist: "Doesn't everyone have his foot in his mouth?"

B

unread,
Aug 24, 2009, 12:27:55 AM8/24/09
to

Andre :

Is the "speculative slant" of my site good or bad? What did you expect
anyway?

I shared the graph we're discussing with Jim Papadopoulos of MIT as
well as the article. He wrote that there is zero technical content to
validate the claims of the plot and hence its meaningless. I also
emailed the author of Frame Forum asking him to correct the
inaccuracies in the definitions of amplitude and frequency, kindly
offering him suggestions. I got a sort of sarcastic and almost pompous
email from him back implying that he's not an expert, yet he believes
in what he wrote, and if he needs more help on uncovering the science
behind "ringing bells", he'll give me a buzz. That I thought was
pretty unprofessional, especially for the admin of a site read by
thousands.What's even strange is that he openly asks for donations
towards his website in spite of inaccuracies in his articles (http://
frameforum.org/forum3/fdp.html). That should take the cake?


BD

B

unread,
Aug 24, 2009, 12:32:05 AM8/24/09
to

Andre :

I'm sorry I don't know your background. Your involvement with the Tour
of Ireland leads me to believe you are based in Ireland, else you're a
traveling photographer or journalist of some sort? Please correct me.


BD

bjwe...@gmail.com

unread,
Aug 24, 2009, 1:21:29 AM8/24/09
to

Cranks, chainrings, chains??? All distractions.
It's not the dynamic properties of wheels that
matter here, it's the dynamic properties of tires.

What you are doing here is like the princess and
the pea story. You're arguing about whether it
matters whether it was a pea or a machine nut
that is under the pile of mattresses, and further
does it matter whether the nut is SAE or metric?
For the rest of us that aren't princesses, the only
thing that matters is whether the mattress is
rated firm or squishy.

Ben

Jan Jolly

unread,
Aug 24, 2009, 2:21:58 AM8/24/09
to
On Aug 24, 1:21 am, "b...@mambo.ucolick.org" <bjwei...@gmail.com>
wrote:

The problem with the pea and princess story is that she wasn't a bike
rider. Its also a fairy tale. Hyuck hyuck....

B

unread,
Aug 24, 2009, 2:25:33 AM8/24/09
to
On Aug 24, 1:21 am, "b...@mambo.ucolick.org" <bjwei...@gmail.com>
wrote:

Dear Ben,

All I'm saying is that bold claims should be validated. Nothing wrong
in discussing sources of vibration in bicycles. This newsgroup is
about discussion so prepare to be a little open minded.


BD

carl...@comcast.net

unread,
Aug 24, 2009, 3:02:04 AM8/24/09
to
On Sun, 23 Aug 2009 23:25:33 -0700 (PDT), B
<1.crazy...@gmail.com> wrote:

>On Aug 24, 1:21锟絘m, "b...@mambo.ucolick.org" <bjwei...@gmail.com>
>wrote:
>> On Aug 23, 4:42锟絧m, B <1.crazyboy.o...@gmail.com> wrote:
>>
>>
>>
>> > On Aug 23, 7:12锟絧m, "b...@mambo.ucolick.org" <bjwei...@gmail.com>


>> > wrote:
>>
>> > > Stop engaging in wishful thinking.
>>
>> > > Capturing the effects of a tire in a study of vibration

>> > > damping is not a drawback. 锟絀t is a necessity, because


>> > > hardly anyone rides a bicycle without tires.
>>
>> > > The test you propose of a bare frame on a table
>> > > would be illegitimate because the input spectrum
>> > > of vibrations to the frame in any real life use is modified
>> > > by the tires, the response is modified by the fact that
>> > > the frame is loaded by the rider's weight, and so on.
>>

>> > > It's all wishful thinking. 锟紺ompared to the soft stuff


>> > > in the system - tires, seats, handlebar tape, arms
>> > > and legs - frames are so much more stiff that there
>> > > is no point in measuring the vibration differences
>> > > between frames and claiming it means something.
>> > > Variations in frame geometry are probably more
>> > > important (slacker head angle for rougher surfaces, etc).
>> > > I have no doubt that someone at this university measured

>> > > vibrations in frames. 锟絋he error is in assuming that


>> > > the measurement shows something meaningful.
>>
>> > > Ben
>>
>> > Ben,
>>
>> > I engaged in wishful thinking only to eliminate the effects of tire
>> > and tube on frame dampening. In reality, you're right, bikes are
>> > ridden with wheels on and they above all see the major impacts of road
>> > surface irregularities. Note that wheels are not the only dynamic
>> > components. Cranks, chainrings and chains are too. It would be hard to
>> > believe that they have zero effect on vibration. Think about a sprint
>> > cyclist running at a top 100-120 RPM and shifting gears along with it.
>> > It would be interested to see if U of Ghent studied the effects these
>> > could have on vibration.
>>

>> Cranks, chainrings, chains??? 锟紸ll distractions.


>> It's not the dynamic properties of wheels that
>> matter here, it's the dynamic properties of tires.
>>
>> What you are doing here is like the princess and

>> the pea story. 锟結ou're arguing about whether it


>> matters whether it was a pea or a machine nut
>> that is under the pile of mattresses, and further
>> does it matter whether the nut is SAE or metric?
>> For the rest of us that aren't princesses, the only
>> thing that matters is whether the mattress is
>> rated firm or squishy.
>>
>> Ben
>
>Dear Ben,
>
>All I'm saying is that bold claims should be validated. Nothing wrong
>in discussing sources of vibration in bicycles. This newsgroup is
>about discussion so prepare to be a little open minded.
>
>
>BD

Dear BD,

According to the data in the article, we need to be open-minded to
damping differences amounting to about 0.5% (at some frequencies, but
not all).

You can think of plenty of 0.5% differences and how unlikely any rider
is to notice them.

Who can tell if he's going 20.0 mph or 20.1 mph just by the difference
in vibration?

Who can tell if his tires are at 100 or at 99.5 psi by just riding
around?

Who can tell the difference by riding in a straight line over normal
pavement between a short, harsh-riding wheelbase of 1,000 mm and a
plush limousine-like wheelbase of 1,005 mm?

Who can feel the difference between a 10.0 mph headwind and a headwind
that's only 9.95 mph?

The colorful and detailed graphs are boldly distracting you from the
obvious lack of scale--all four frames damp <1%, meaning that they all
transmit >99% of vibration.

200 dots:
.........................
.........................
.........................
.........................
.........................
.........................
.........................
.........................

99.5% of 200 dots:
.........................
.........................
.........................
.........................
........ ................
.........................
.........................
.........................

Cheers,

Carl Fogel

Andre Jute

unread,
Aug 24, 2009, 3:47:45 AM8/24/09
to

Good. There has to be a place for speculation. Newton's E=mc^1
worldview held sway for centuries. What would happened no one
speculated about the connection between mass and energy?

> What did you expect
> anyway?

Of a netsite on the internet? Precisely that it should be speculative,
interactive, open opinions and mechanisms outside the mainstream. Far
too many aren't. The net has been a disappointment to me; such a
wasted opportunity.

If you mean, what did I expect of RBT? Actually not much more than I
found, mainly jumped-up techies trying to be polemicists, frightened
little people whose role as cycling "experts" define them even in
their own eyes; a handful of worthwhile, knowledgeable folk. One finds
that on every technical conference. There was a period when
rec.audio.tubes (RAT) rose beyond that but it lasted perhaps two
years, and to outward appearances it was a minefield of flame wars
every day of those two glorious years. I suspect RBT's glory days were
over even before Sheldon Brown died. The Usenet too could have been so
much more than it has become.

> I shared the graph we're discussing with Jim Papadopoulos of MIT as
> well as the article. He wrote that there is zero technical content to
> validate the claims of the plot and hence its meaningless. I also
> emailed the author of Frame Forum asking him to correct the
> inaccuracies in the definitions of amplitude and frequency, kindly
> offering him suggestions. I got a sort of sarcastic and almost pompous
> email from him back implying that he's not an expert, yet he believes
> in what he wrote, and if he needs more help on uncovering the science
> behind "ringing bells", he'll give me a buzz. That I thought was
> pretty unprofessional, especially for the admin of a site read by
> thousands.What's even strange is that he openly asks for donations
> towards his website in spite of inaccuracies in his articles (http://
> frameforum.org/forum3/fdp.html). That should take the cake?
>
> BD

Zero surprise on both counts. Pappadopoulos is just saying what
several parties, and I, have said here already. And that some amateur
journalist should treat generously offered expert help with snotty
disdain is par for the course. He probably believes that's how the
professionals behave...

Andre Jute
Visit Jute on Amps at
http://www.audio-talk.co.uk/fiultra/
"wonderfully well written and reasoned information for the tube audio
constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site containing vital gems of
wisdom"
Stuart Perry Hi-Fi News & Record Review

Andre Jute

unread,
Aug 24, 2009, 3:54:40 AM8/24/09
to

I'm a writer; some of my books are listed on my net site:
http://www.audio-talk.co.uk/fiultra/THE%20WRITER'S%20HOUSE.html

Andre Jute
Not everything in materials is dreamt of in Timoshenko

Andre Jute

unread,
Aug 24, 2009, 3:57:45 AM8/24/09
to
On Aug 24, 8:02 am, carlfo...@comcast.net wrote:
> On Sun, 23 Aug 2009 23:25:33 -0700 (PDT), B
>
>
>
>
>
> <1.crazyboy.o...@gmail.com> wrote:
> >On Aug 24, 1:21 am, "b...@mambo.ucolick.org" <bjwei...@gmail.com>
> >wrote:
> >> On Aug 23, 4:42 pm, B <1.crazyboy.o...@gmail.com> wrote:
>
> >> > On Aug 23, 7:12 pm, "b...@mambo.ucolick.org" <bjwei...@gmail.com>

> >> > wrote:
>
> >> > > Stop engaging in wishful thinking.
>
> >> > > Capturing the effects of a tire in a study of vibration
> >> > > damping is not a drawback.  It is a necessity, because

> >> > > hardly anyone rides a bicycle without tires.
>
> >> > > The test you propose of a bare frame on a table
> >> > > would be illegitimate because the input spectrum
> >> > > of vibrations to the frame in any real life use is modified
> >> > > by the tires, the response is modified by the fact that
> >> > > the frame is loaded by the rider's weight, and so on.
>
> >> > > It's all wishful thinking.  Compared to the soft stuff

> >> > > in the system - tires, seats, handlebar tape, arms
> >> > > and legs - frames are so much more stiff that there
> >> > > is no point in measuring the vibration differences
> >> > > between frames and claiming it means something.
> >> > > Variations in frame geometry are probably more
> >> > > important (slacker head angle for rougher surfaces, etc).
> >> > > I have no doubt that someone at this university measured
> >> > > vibrations in frames.  The error is in assuming that

> >> > > the measurement shows something meaningful.
>
> >> > > Ben
>
> >> > Ben,
>
> >> > I engaged in wishful thinking only to eliminate the effects of tire
> >> > and tube on frame dampening. In reality, you're right, bikes are
> >> > ridden with wheels on and they above all see the major impacts of road
> >> > surface irregularities. Note that wheels are not the only dynamic
> >> > components. Cranks, chainrings and chains are too. It would be hard to
> >> > believe that they have zero effect on vibration. Think about a sprint
> >> > cyclist running at a top 100-120 RPM and shifting gears along with it.
> >> > It would be interested to see if U of Ghent studied the effects these
> >> > could have on vibration.
>
> >> Cranks, chainrings, chains???  All distractions.

> >> It's not the dynamic properties of wheels that
> >> matter here, it's the dynamic properties of tires.
>
> >> What you are doing here is like the princess and
> >> the pea story.  You're arguing about whether it

Dear Carl,

It is politically very incorrect to notice that the qualities of some
natural materials are much akin to snake oil. Flax is one of those
which are presumed holier than spandex.

I trust this will preserve you from committing further solecisms.

Andre Jute
Reformed petrol head
Car-free since 1992
Greener than thou!

someone

unread,
Aug 24, 2009, 4:53:45 AM8/24/09
to

Works on baseball and cricket bats.

Johnny Twelve-Point presented by JFT

unread,
Aug 24, 2009, 6:47:28 AM8/24/09
to
On Sun, 23 Aug 2009 23:25:33 -0700 (PDT), B
<1.crazy...@gmail.com> wrote:

>On Aug 24, 1:21嚙窮m, "b...@mambo.ucolick.org" <bjwei...@gmail.com>
>wrote:
>> On Aug 23, 4:42嚙緘m, B <1.crazyboy.o...@gmail.com> wrote:
>>
>>
>>
>> > On Aug 23, 7:12嚙緘m, "b...@mambo.ucolick.org" <bjwei...@gmail.com>


>> > wrote:
>>
>> > > Stop engaging in wishful thinking.
>>
>> > > Capturing the effects of a tire in a study of vibration

>> > > damping is not a drawback. 嚙瘢t is a necessity, because


>> > > hardly anyone rides a bicycle without tires.
>>
>> > > The test you propose of a bare frame on a table
>> > > would be illegitimate because the input spectrum
>> > > of vibrations to the frame in any real life use is modified
>> > > by the tires, the response is modified by the fact that
>> > > the frame is loaded by the rider's weight, and so on.
>>

>> > > It's all wishful thinking. 嚙瘠ompared to the soft stuff


>> > > in the system - tires, seats, handlebar tape, arms
>> > > and legs - frames are so much more stiff that there
>> > > is no point in measuring the vibration differences
>> > > between frames and claiming it means something.
>> > > Variations in frame geometry are probably more
>> > > important (slacker head angle for rougher surfaces, etc).
>> > > I have no doubt that someone at this university measured

>> > > vibrations in frames. 嚙確he error is in assuming that


>> > > the measurement shows something meaningful.
>>
>> > > Ben
>>
>> > Ben,
>>
>> > I engaged in wishful thinking only to eliminate the effects of tire
>> > and tube on frame dampening. In reality, you're right, bikes are
>> > ridden with wheels on and they above all see the major impacts of road
>> > surface irregularities. Note that wheels are not the only dynamic
>> > components. Cranks, chainrings and chains are too. It would be hard to
>> > believe that they have zero effect on vibration. Think about a sprint
>> > cyclist running at a top 100-120 RPM and shifting gears along with it.
>> > It would be interested to see if U of Ghent studied the effects these
>> > could have on vibration.
>>

>> Cranks, chainrings, chains??? 嚙璀ll distractions.


>> It's not the dynamic properties of wheels that
>> matter here, it's the dynamic properties of tires.
>>
>> What you are doing here is like the princess and

>> the pea story. 嚙磐ou're arguing about whether it


>> matters whether it was a pea or a machine nut
>> that is under the pile of mattresses, and further
>> does it matter whether the nut is SAE or metric?
>> For the rest of us that aren't princesses, the only
>> thing that matters is whether the mattress is
>> rated firm or squishy.
>>
>> Ben
>
>Dear Ben,
>
>All I'm saying is that bold claims should be validated. Nothing wrong
>in discussing sources of vibration in bicycles. This newsgroup is
>about discussion so prepare to be a little open minded.


Yeah. I'm way way skeptical of the claims in that ad, but the
immediate dismissal of what seems a valid approach to measuring things
is strange. I'd like to see those sorts of measurements done in a
clearly neutral way of different frames built with the same equipment
and tires.

Johnny Twelve-Point presented by JFT

unread,
Aug 24, 2009, 6:49:32 AM8/24/09
to
On Mon, 24 Aug 2009 01:02:04 -0600, carl...@comcast.net wrote:

>You can think of plenty of 0.5% differences and how unlikely any rider
>is to notice them.

Just because someone doesn't notice something doesn't mean it isn't
real.

Although, if I followed you generall philosophy and tossed out
everything that gave a 0.5% difference, they'd add up to something
noticeable. I would know what specifically, but at some point things
would become noticeable.

Johnny Twelve-Point presented by JFT

unread,
Aug 24, 2009, 6:52:19 AM8/24/09
to
On Mon, 24 Aug 2009 01:02:04 -0600, carl...@comcast.net wrote:

>Who can tell if his tires are at 100 or at 99.5 psi by just riding
>around?

I don't think tire pressure works that way. I think it takes a couple
PSI to get .5% more or less comfort.

And I've ridden with tires 20psi low (due to a leak) and not noticed
it while riding, due to other circumstances where I was paying more
attention to other things.

Does that mean 20psi doesn't matter in terms of rolling resistance or
safety, just because I didn't notice it?

jim beam

unread,
Aug 24, 2009, 11:06:35 AM8/24/09
to
barbara cartland illiterately bleated:

...

> There has to be a place for speculation. Newton's E=mc^1
> worldview held sway for centuries. What would happened no one
> speculated about the connection between mass and energy?

...

"What would happened no one speculated about the... " ???

andre, not only are you fucking illiterate, your ignorance of newton's
[and einstein's] work is simply perverse.

64-year old schizo narcissistic pervert idiot imposters untie! andre
jute is your lrod!

http://home.comcast.net/~czell/densaapp.htm

Daflex

unread,
Aug 24, 2009, 11:28:18 AM8/24/09
to
Hi guys,

I'm actually the person who performed these tests and I have to say
that the original article on Frameforum dropped the ball on a couple
of points. I prepared a technical presentation for the Museeuw Bikes
press launch, which I also presented and could thus explain in more
detail. A copy of this presentation somehow made it to the guys at
Frameforum who picked it up without the proper technical
explanations. I will attend Eurobike, so if any of you have any
questions please come by the Museeuw bikes booth and I will gladly
answer all questions.

For those of you that will not be able to make it to Eurobike next
week, let me explain below what the graphs show and how I got to make
the assumptions...

In measuring comfort, there is no straigthforward way to do so.
Putting the frame on a shaker might give some indication but you will
never get an actual real-life simulation on a shaker table. Also,
riding behaviour and road conditions greatly influences how loads are
introduced into the frame not to mention tire pressures, rim height
and so on... The only way to get some trend/indication on vibration
damping was to get the same rider do the exact same route (long enough
to determine a visual trend in the results and possibly filter out any
variations) and strategically position accelerometers to get good and
reliable datasets. On cobblestones every frame will transfer the
vibration and it is not these vibrations which were of interest to
us. Low frequency vibrations already cause significant energy loss
and these can already be felt on concrete road or badly maintained
roads. I therefore took a very basic route with some good and some bad
road conditions and avoiding extreme conditions.

The general idea was: if I could find a way to correctly measure and
determine the difference between the loads that were introduced into
the frame and the loads that the rider would experience, I could find
out how "comfortable" a bicycle frame is quantitatively. Therefore,
placing one accelerometer on the rearstay, near the rear wheel hub
would get me the loads coming into the frame and an accelerometer
positioned just below the saddle would get me the loads before the
rider experiences them. The reason why I used 5 accelerometers was to
gain insight on the effect of the design of each specific frame
structure (ISP/no ISP, curved vs. straight rearstay,...). In the
future I will try to analyse this data as well but for now I only
focused the rear stay and seatpost data to get the broader picture.

Every testframe (Museeuw MF5, Pinarello Prince, Wilier Cento Uno and
Cervelo R3SL) was tested 4 times: 2 clincher type rims (high and low
profile) and 2 tubular (high and low). If my idea was correct, I
should not see too much difference between different wheelsets since I
was looking at the frame properties (between rearstay and saddle).
Final results showed a margin of difference less than 5%. The
measurements were done using independent accelerometers at a measuring
rate of 50 Hz. The accelerometers were synchronized before the test.
This enabled me to obtain a frequency spectrum of 0 to 25 Hz at any
given time after putting the datasets through a Fast Fourier
Transformation. The test method is comparable to how construction
workers are monitored for whole-body-vibrations during their work.

For every 27-second interval I used an FFT-algorithm to get a 2D
frequency spectrum, i.e. "frequency vs. load" graph. By using the 27-
second interval I could avoid any response delay of the frame when
impacted. By comparing each individual 27-second frequency spectrum of
the rearstay and seatpost at the same interval I was able to construct
the nice 3D graphs (appr. 300 graphs put next to eachother) that were
shown on Frameforum. I have to apologize for naming my axes,
especially the y-axis since it actually shows how much of the original
load is being absorbed. "0,8" actually means that 80 percent of the
original load is being absorbed/dampened somewhere between rearstay
and seatpost and NOT 0,8 percent. So the MF-5 dampens around 70
percent of the original load as where the Pinarello Prince absorbs
only 45 percent of the original load measured at the rear stay.


A new website for Museeuw Bikes will be launched shortly after
Eurobike and it will contain an R&D section where you will be able to
find all data and facts on these tests with a more elaborate
explanation and also a short explanation on the activities we are
planning with Ghent University to further expand the Flax technology
in bicycles.


Thanks for your interest!


Best regards,


Dave Luyckx

jim beam

unread,
Aug 24, 2009, 11:53:21 AM8/24/09
to

dave, thank you for following up. personally speaking, i welcome anyone
who puts up hard numbers rather than mere speculative b.s.

it's a tough sell to this audience though.

1. most disregard most any new info as "sales".

2. some are scientifically [and sometimes literally] illiterate

the most vocal are typically people who occupy /both/ categories and who
have no experience of composites whatsoever. disappointing though this
may be for a forum purporting to be "tech", you'll need to dumb down
accordingly.

keep the data coming.

and good luck!

jim beam

unread,
Aug 24, 2009, 11:59:14 AM8/24/09
to

i should add one credential for those that don't know: the university of
ghent is highly regarded in materials, particularly composites - the
aerospace material "glare" is one of theirs.

B

unread,
Aug 24, 2009, 12:04:02 PM8/24/09
to
On Aug 24, 3:02 am, carlfo...@comcast.net wrote:
> On Sun, 23 Aug 2009 23:25:33 -0700 (PDT), B
>
>
>
> <1.crazyboy.o...@gmail.com> wrote:
> >On Aug 24, 1:21 am, "b...@mambo.ucolick.org" <bjwei...@gmail.com>
> >wrote:
> >> On Aug 23, 4:42 pm, B <1.crazyboy.o...@gmail.com> wrote:
>
> >> > On Aug 23, 7:12 pm, "b...@mambo.ucolick.org" <bjwei...@gmail.com>

> >> > wrote:
>
> >> > > Stop engaging in wishful thinking.
>
> >> > > Capturing the effects of a tire in a study of vibration
> >> > > damping is not a drawback.  It is a necessity, because

> >> > > hardly anyone rides a bicycle without tires.
>
> >> > > The test you propose of a bare frame on a table
> >> > > would be illegitimate because the input spectrum
> >> > > of vibrations to the frame in any real life use is modified
> >> > > by the tires, the response is modified by the fact that
> >> > > the frame is loaded by the rider's weight, and so on.
>
> >> > > It's all wishful thinking.  Compared to the soft stuff

> >> > > in the system - tires, seats, handlebar tape, arms
> >> > > and legs - frames are so much more stiff that there
> >> > > is no point in measuring the vibration differences
> >> > > between frames and claiming it means something.
> >> > > Variations in frame geometry are probably more
> >> > > important (slacker head angle for rougher surfaces, etc).
> >> > > I have no doubt that someone at this university measured
> >> > > vibrations in frames.  The error is in assuming that

> >> > > the measurement shows something meaningful.
>
> >> > > Ben
>
> >> > Ben,
>
> >> > I engaged in wishful thinking only to eliminate the effects of tire
> >> > and tube on frame dampening. In reality, you're right, bikes are
> >> > ridden with wheels on and they above all see the major impacts of road
> >> > surface irregularities. Note that wheels are not the only dynamic
> >> > components. Cranks, chainrings and chains are too. It would be hard to
> >> > believe that they have zero effect on vibration. Think about a sprint
> >> > cyclist running at a top 100-120 RPM and shifting gears along with it.
> >> > It would be interested to see if U of Ghent studied the effects these
> >> > could have on vibration.
>
> >> Cranks, chainrings, chains???  All distractions.

> >> It's not the dynamic properties of wheels that
> >> matter here, it's the dynamic properties of tires.
>
> >> What you are doing here is like the princess and
> >> the pea story.  You're arguing about whether it

Carl and others,

This morning, I obtained the following information from the person who
actually conducted the study. See below :

in bicycles.""""'

Please note, above information was quoted.
BD

Lou Holtman

unread,
Aug 24, 2009, 12:04:55 PM8/24/09
to
jim beam schreef:

>
> i should add one credential for those that don't know: the university of
> ghent is highly regarded in materials, particularly composites - the
> aerospace material "glare" is one of theirs.


I thought Glare was an development of the Delft University of Technology.

Lou

jim beam

unread,
Aug 24, 2009, 12:10:09 PM8/24/09
to

actually, you're right! delft/ghent - insert "all the same to me"
statement here.

bjwe...@gmail.com

unread,
Aug 24, 2009, 2:15:58 PM8/24/09
to
On Aug 24, 3:47 am, Johnny Twelve-Point presented by JFT

<usenetrem...@jt10000.com> wrote:
> On Sun, 23 Aug 2009 23:25:33 -0700 (PDT), B
>
>
>
> <1.crazyboy.o...@gmail.com> wrote:
> >On Aug 24, 1:21 am, "b...@mambo.ucolick.org" <bjwei...@gmail.com>
> >wrote:
> >> On Aug 23, 4:42 pm, B <1.crazyboy.o...@gmail.com> wrote:
>
> >> > On Aug 23, 7:12 pm, "b...@mambo.ucolick.org" <bjwei...@gmail.com>

> >> > wrote:
>
> >> > > Stop engaging in wishful thinking.
>
> >> > > Capturing the effects of a tire in a study of vibration
> >> > > damping is not a drawback.  It is a necessity, because

> >> > > hardly anyone rides a bicycle without tires.
>
> >> > > The test you propose of a bare frame on a table
> >> > > would be illegitimate because the input spectrum
> >> > > of vibrations to the frame in any real life use is modified
> >> > > by the tires, the response is modified by the fact that
> >> > > the frame is loaded by the rider's weight, and so on.
>
> >> > > It's all wishful thinking.  Compared to the soft stuff

> >> > > in the system - tires, seats, handlebar tape, arms
> >> > > and legs - frames are so much more stiff that there
> >> > > is no point in measuring the vibration differences
> >> > > between frames and claiming it means something.
> >> > > Variations in frame geometry are probably more
> >> > > important (slacker head angle for rougher surfaces, etc).
> >> > > I have no doubt that someone at this university measured
> >> > > vibrations in frames.  The error is in assuming that

> >> > > the measurement shows something meaningful.
>
> >> > > Ben
>
> >> > Ben,
>
> >> > I engaged in wishful thinking only to eliminate the effects of tire
> >> > and tube on frame dampening. In reality, you're right, bikes are
> >> > ridden with wheels on and they above all see the major impacts of road
> >> > surface irregularities. Note that wheels are not the only dynamic
> >> > components. Cranks, chainrings and chains are too. It would be hard to
> >> > believe that they have zero effect on vibration. Think about a sprint
> >> > cyclist running at a top 100-120 RPM and shifting gears along with it.
> >> > It would be interested to see if U of Ghent studied the effects these
> >> > could have on vibration.
>
> >> Cranks, chainrings, chains???  All distractions.

> >> It's not the dynamic properties of wheels that
> >> matter here, it's the dynamic properties of tires.
>
> >> What you are doing here is like the princess and
> >> the pea story.  You're arguing about whether it

> >> matters whether it was a pea or a machine nut
> >> that is under the pile of mattresses, and further
> >> does it matter whether the nut is SAE or metric?
> >> For the rest of us that aren't princesses, the only
> >> thing that matters is whether the mattress is
> >> rated firm or squishy.
>
> >> Ben
>
> >Dear Ben,
>
> >All I'm saying is that bold claims should be validated. Nothing wrong
> >in discussing sources of vibration in bicycles. This newsgroup is
> >about discussion so prepare to be a little open minded.

"Keep an open mind, but not so open your
brain falls out."

It's generally impossible to make a full model of any
physical situation from first principles. You have to make
approximations. That means you have to know what can
be safely approximated. A scientist or engineer has to learn
to discriminate between factors that are important and
unimportant, and not spend much of his or her time thinking
about factors that are prima facie unimportant.

In this case, when I point out that the effects of squishy
things (tires, seat) on vibration damping are going to dwarf
the effects of a rigid frame, and you respond by saying
that we need to think about not just wheels but cranks
and chainrings, I have to conclude that you're missing
the point.

> Yeah.  I'm way way skeptical of the claims in that ad, but the
> immediate dismissal of what seems a valid approach to measuring things
> is strange.  I'd like to see those sorts of measurements done in a
> clearly neutral way of different frames built with the same equipment
> and tires.

My complaint is not with the idea that one should strap
accelerometers to bicycles and measure a vibration
amplitude and spectrum. That's actually potentially
interesting. As you can see above, I think taking
measurements on an as-ridden bicycle is more valid
than just putting the frames on a shaker table.

My complaint is first with the interpretation - the faults
of that article/puff-piece have been discussed - and second
with the experimental design. If you strap accelerometers
in the same place on several rigid frames with the same
equipment, tire PSI, etc, you're designing an experiment
that can only tell you the size of the difference between
frames, which is great for frame-adverts but not so great
since we think that the non-rigid parts are probably
more important than the difference between frames.

For example, it would be far more interesting to do the
experiment with: (a) one or more accelerometers mounted
at a rider's point of contact (seat, bars, or even strapped
to the rider); (b) tires at two different pressures, say 80 and
120 psi; (c) tires of two different sizes; and so on.

If you did this you could begin to quantify the difference
made by factors such as tire pressure. I think that the
difference between 80 and 120 psi or 700x19 and 700x23
at pressures sufficient to avoid pinchflats would be far bigger
than the difference between frames, but I don't _know_ that.
Measuring such numbers is something that one would
want to know before interpreting the difference-between-
frame numbers.

Ben

B

unread,
Aug 24, 2009, 2:50:37 PM8/24/09
to

Dear Dave Luyckx,

It would be interesting to know what your credentials are and where
you work. Anyway, I read this piece from you. One on the assumptions
in the study by you is that vibration loads just finds its way somehow
unattenuated to the frame and you can measure this by placing an
accelerometer on rear stay, near the hub of the wheel. I will doubt
this thought process unless you can show in a report that attenuation
of vibration due to the pressure of the tires is so small, it can be
neglected so as to assume everything is going into the frame. I doubt
it is small. Knobby mountain bike tires with 35-40 psi of pressure
capture a lot of vibration through deformation and energy transfer.
The effect of tires, tubes and wheels on vibration have to be captured
in your road study. Still an interesting graph.


BD
http://cozybeehive.blogspot.com

Jan Jolly

unread,
Aug 24, 2009, 3:02:17 PM8/24/09
to

Did a search for 'David Luyckx'. Found this http://www.linkedin.com/pub/dave-luyckx/a/251/399

"Dave Luyckx
Engineer, Materials Engineering at Toyota Motor Europe
View full profile | Contact Dave Luyckx
Currently: Engineer, Materials Engineering at Toyota Motor Europe,
Belgium
Education:Technische Universiteit Delft "

Is this correct? Why is someone from Toyota involved in Museeuw's
business.

jim beam

unread,
Aug 24, 2009, 3:02:23 PM8/24/09
to

while you're correct in principle, there's one point you're missing -
for any two frames, the wheels/tires, etc are constant. thus if the
frame and frame materials are different, that which gets through the
tire/wheel/etc. /is/ a variable.


>
>> Yeah. �I'm way way skeptical of the claims in that ad, but the
>> immediate dismissal of what seems a valid approach to measuring things
>> is strange. �I'd like to see those sorts of measurements done in a
>> clearly neutral way of different frames built with the same equipment
>> and tires.
>
> My complaint is not with the idea that one should strap
> accelerometers to bicycles and measure a vibration
> amplitude and spectrum. That's actually potentially
> interesting. As you can see above, I think taking
> measurements on an as-ridden bicycle is more valid
> than just putting the frames on a shaker table.

but physically harder to do. again, if the conditions are constant and
the frame/frame material is the variable, use of "replicated" load is valid.


>
> My complaint is first with the interpretation - the faults
> of that article/puff-piece have been discussed - and second
> with the experimental design. If you strap accelerometers
> in the same place on several rigid frames with the same
> equipment, tire PSI, etc, you're designing an experiment
> that can only tell you the size of the difference between
> frames, which is great for frame-adverts but not so great
> since we think that the non-rigid parts are probably
> more important than the difference between frames.
>
> For example, it would be far more interesting to do the
> experiment with: (a) one or more accelerometers mounted
> at a rider's point of contact (seat, bars, or even strapped
> to the rider); (b) tires at two different pressures, say 80 and
> 120 psi; (c) tires of two different sizes; and so on.

maybe, but if they're constants...


>
> If you did this you could begin to quantify the difference
> made by factors such as tire pressure. I think that the
> difference between 80 and 120 psi or 700x19 and 700x23
> at pressures sufficient to avoid pinchflats would be far bigger
> than the difference between frames, but I don't _know_ that.

you probably do. i do. but that's not the point. the point is,
despite the fact that 3" diameter solid steel bar can transmit the same
static force as a 2" thin wall composite tube, its ability to transmit
dynamic load is completely different. thus, much like different tires
ride different due to different casing fibers, even though they're
transmitting the same static loads, there's no reason a frames of
different fabrications can't ride different either.


> Measuring such numbers is something that one would
> want to know before interpreting the difference-between-
> frame numbers.

just measure the variables - it's much more important.

Lou Holtman

unread,
Aug 24, 2009, 3:02:52 PM8/24/09
to
B schreef:

No, he does not made that assumption. The vibrations measured at the
chainstay is the imput and the vibrations measured at the seatpost are
the output. The difference is what the frame does between those points.
Simple. If that is a valid representaion what the road introduce in the
system and what the rider feels is another matter. An important matter
though and for most of us the only thing that counts.

to the frame and you can measure this by placing an
> accelerometer on rear stay, near the hub of the wheel. I will doubt
> this thought process unless you can show in a report that attenuation
> of vibration due to the pressure of the tires is so small, it can be
> neglected so as to assume everything is going into the frame.

False interpretation.

Lou

jim beam

unread,
Aug 24, 2009, 3:08:11 PM8/24/09
to

why? do you think you're better qualified? are you itching for a
jobst-style credentials pissing contest?

bottom line is content dude. jobst has "credentials" but is utterly
wrong on more fundamentals than any person in his purported field can
believe. someone actually knowing what they're talking about counts way
more than some proven fool merely saying they do.


> Anyway, I read this piece from you. One on the assumptions
> in the study by you is that vibration loads just finds its way somehow
> unattenuated to the frame and you can measure this by placing an
> accelerometer on rear stay, near the hub of the wheel. I will doubt
> this thought process unless you can show in a report that attenuation
> of vibration due to the pressure of the tires is so small, it can be
> neglected so as to assume everything is going into the frame. I doubt
> it is small. Knobby mountain bike tires with 35-40 psi of pressure
> capture a lot of vibration through deformation and energy transfer.
> The effect of tires, tubes and wheels on vibration have to be captured
> in your road study. Still an interesting graph.
>
>
> BD
> http://cozybeehive.blogspot.com

you have no content - only underinformed opinion.

jim beam

unread,
Aug 24, 2009, 3:09:02 PM8/24/09
to

ever heard of "consultants" or "experts"???

jim beam

unread,
Aug 24, 2009, 3:11:24 PM8/24/09
to

indeed.

RonSonic

unread,
Aug 24, 2009, 3:18:40 PM8/24/09
to
On Mon, 24 Aug 2009 12:02:17 -0700 (PDT), Jan Jolly <fanofc...@gmail.com>
wrote:

Engineers are the migrant labor of the industrial world. A lot of job mobility,
moonlighting, consultation and outside projects. It's a good thing really.
Better for the employer than if they take up carpentry or gambling or bike
racing. Better for the employee, too.

--


Oh damn. There's that annoying blog. Again. http://dumbbikeblog.blogspot.com

carl...@comcast.net

unread,
Aug 24, 2009, 3:14:43 PM8/24/09
to

Dear Bd,

Sounds even more confused.

As usual, it will all be explained at some future time.

Cheers,

Carl Fogel

B

unread,
Aug 24, 2009, 4:44:12 PM8/24/09
to

Lou,

Alright, we'll take your interpretation. So Dave calls his input
signal as the one on the rearstay near the hub and output as the one
on the seatpost, just below the saddle, Now take note that the report
from Dave does not tell us what seatpost was used, what its material
makeup was and whether all bikes used the same seatposts. If these 4
bikes were stock bikes picked up from a shop, it's likely they came
with different components on them. So there's not much evidence
supplied that the output signal captured is reasonable within the
framework of the experimental design among 3 different bikes.

Moreover, we can safely assume that the design of bikes, especially
their front and rear triangle,may (or may not) play a role in
vibration dampening effects. Over the past decades, bike manufacturers
have been marketing all kinds of geometries on seat stays and chain
stays, making us believe that they have something to do with vibration
soaking and compliancy. As examples, Pinarello's curvy frame and fork
design and Colnago's Diamond shaped chainstays are purported to have
something to do with vibration dampening, power transfer, compliancy
and yada yada. Atleast they are cleverly marketed this way even though
zero technical validation exists for these claims. If we assume that
to be true anyway and if 4 different bikes in this study are designed
in 4 different ways and have 4 different seat positions, there must be
a component of vibration which could be affected by the design itself
until proven to be not present. I think to control for errors from an
aspect like that, you need to test bikes with the same general
geometrical parameters, seating position and saddle but made of
different materials, one of which can be the flax-carbon composite.
Then we can see what the effect of one material over another is in in
a bike as far as vibration is concerned.

Accelerometers measure acceleration in units of g's, not force or
"load". If Dave wanted to measure comfort on the rider as a function
of whole body vibration, how could he and his instruments
differentiate between the acceleration near the hub on the rearstay
and the accelerations on the seattube near the saddle when the bike
goes over bumps on the road? Shouldn't the acceleration of those two
points be the same?

This study from Dave's account is not convincing as far as the
experimental design was setup and what he sought out to measure. I
would point Dave to ISO test standards ISO 2631-1 : Mechanical
Vibration and Shock - Evaluation of Human Exposure to Whole-Body
Vibration General Requirements and ISO 2631-5 : Mechanical vibration
and shock -- Evaluation of human exposure to whole-body vibration -
Method for evaluation of vibration containing multiple shocks.

A study such as this one is really challenging and unless there is
convincing experiments, convincing data and logical conclusions, you
can't claim one frame as having more vibration dampening than another,
atleast from an engineering standpoint. Marketing is another thing.


BD
http://cozybeehive.blogspot.com

jim beam

unread,
Aug 24, 2009, 5:07:03 PM8/24/09
to

dude, have you /ever/ studied high school physics? have you the
slightest clue about F=ma? if you know m, which you do, and you know a,
which you've just measured, do you think you could do the math on F?


> If Dave wanted to measure comfort on the rider as a function
> of whole body vibration, how could he and his instruments
> differentiate between the acceleration near the hub on the rearstay
> and the accelerations on the seattube near the saddle when the bike
> goes over bumps on the road? Shouldn't the acceleration of those two
> points be the same?
>
> This study from Dave's account is not convincing as far as the
> experimental design was setup and what he sought out to measure.

only if you're clueless.


> I
> would point Dave to ISO test standards ISO 2631-1 : Mechanical
> Vibration and Shock - Evaluation of Human Exposure to Whole-Body
> Vibration General Requirements and ISO 2631-5 : Mechanical vibration
> and shock -- Evaluation of human exposure to whole-body vibration -
> Method for evaluation of vibration containing multiple shocks.
>
> A study such as this one is really challenging and unless there is
> convincing experiments, convincing data and logical conclusions, you
> can't claim one frame as having more vibration dampening than another,
> atleast from an engineering standpoint. Marketing is another thing.
>
>
> BD
> http://cozybeehive.blogspot.com

how can you "convince" the clueless? clearly not by presenting evidence
since the clueless don't know what they're looking at.

Lou Holtman

unread,
Aug 24, 2009, 5:07:23 PM8/24/09
to

I agree with you. Seatposts make a great difference. As many frame/bike
manufacturers acknowledge now that comfort is a selling point we see a
shift in seatpost diameter from 31.6 mm to the good old 27.2 mm in
carbon with a setback.


>
> Moreover, we can safely assume that the design of bikes, especially
> their front and rear triangle,may (or may not) play a role in
> vibration dampening effects. Over the past decades, bike manufacturers
> have been marketing all kinds of geometries on seat stays and chain
> stays, making us believe that they have something to do with vibration
> soaking and compliancy.

Yep. When I was in the proces of buying a Ti frme I could choose between
straight seatstay and a curved one. The latter cost an extra 200 euro.
I did some FEA and it saved me the 200 euro because I concluded that the
0.2 mm extra vertical compliance of the curved seatstays was not worth it.

As examples, Pinarello's curvy frame and fork
> design and Colnago's Diamond shaped chainstays are purported to have
> something to do with vibration dampening, power transfer, compliancy
> and yada yada.

Yep I read a similar test about thos Colnago chainstays. The results
were embarrassing like a said in an earlier post.

Atleast they are cleverly marketed this way even though
> zero technical validation exists for these claims. If we assume that
> to be true anyway and if 4 different bikes in this study are designed
> in 4 different ways and have 4 different seat positions, there must be
> a component of vibration which could be affected by the design itself
> until proven to be not present. I think to control for errors from an
> aspect like that, you need to test bikes with the same general
> geometrical parameters, seating position and saddle but made of
> different materials, one of which can be the flax-carbon composite.
> Then we can see what the effect of one material over another is in in
> a bike as far as vibration is concerned.

The measurements Dave did are what they are. We have to interpretate
them ourselves. We can question his inerpretation/conclusions not the
numbers.

>
> Accelerometers measure acceleration in units of g's, not force or
> "load". If Dave wanted to measure comfort on the rider as a function
> of whole body vibration, how could he and his instruments
> differentiate between the acceleration near the hub on the rearstay
> and the accelerations on the seattube near the saddle when the bike
> goes over bumps on the road? Shouldn't the acceleration of those two
> points be the same?


>
> This study from Dave's account is not convincing as far as the
> experimental design was setup and what he sought out to measure. I
> would point Dave to ISO test standards ISO 2631-1 : Mechanical
> Vibration and Shock - Evaluation of Human Exposure to Whole-Body
> Vibration General Requirements and ISO 2631-5 : Mechanical vibration
> and shock -- Evaluation of human exposure to whole-body vibration -
> Method for evaluation of vibration containing multiple shocks.
>
> A study such as this one is really challenging and unless there is
> convincing experiments, convincing data and logical conclusions, you
> can't claim one frame as having more vibration dampening than another,
> atleast from an engineering standpoint. Marketing is another thing.

I agree.

Lou

Jan Jolly

unread,
Aug 24, 2009, 5:25:14 PM8/24/09
to

Shut up you Beamer nitwit. You offer zero arguments as well, just crap.

jim beam

unread,
Aug 24, 2009, 5:32:20 PM8/24/09
to

have you figured out your high school F=ma yet?

Jan Jolly

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Aug 24, 2009, 5:39:13 PM8/24/09
to

Idiot. Wasn't your account banned by Google Groups? Take your crap
elsewhere.

jim beam

unread,
Aug 24, 2009, 6:10:04 PM8/24/09
to

"my account"??? you mean "m...@privacy.net", the email address used
wholesale throughout the net to fudge spammers? seems you don't know
much about usenet!

btw, i don't use google groups. nor would you if you had any sense.

Johnny Twelve-Point presented by JFT

unread,
Aug 24, 2009, 6:19:27 PM8/24/09
to
On Mon, 24 Aug 2009 08:53:21 -0700, jim beam <m...@privacy.net> wrote:

>it's a tough sell to this audience though.
>
>1. most disregard most any new info as "sales".
>
>2. some are scientifically [and sometimes literally] illiterate

You left out

3. If it's supposed to make the cyclist faster, they believe it's
inherently bogus.

Johnny Twelve-Point presented by JFT

unread,
Aug 24, 2009, 6:21:45 PM8/24/09
to
On Mon, 24 Aug 2009 11:15:58 -0700 (PDT), "b...@mambo.ucolick.org"
<bjwe...@gmail.com> wrote:

>My complaint is first with the interpretation - the faults
>of that article/puff-piece have been discussed - and second
>with the experimental design. If you strap accelerometers
>in the same place on several rigid frames with the same
>equipment, tire PSI, etc, you're designing an experiment
>that can only tell you the size of the difference between
>frames, which is great for frame-adverts but not so great
>since we think that the non-rigid parts are probably
>more important than the difference between frames.

Yes

Andre Jute

unread,
Aug 24, 2009, 6:48:38 PM8/24/09
to

I see: an unauthorized interpretation of an unreleased report. That
blogger, or whatever he is, is a tenth-rate idiot both technically and
as a writer.

Thanks for coming here to sort it out, Dave.

Andre Jute
Visit Andre's books at
http://www.audio-talk.co.uk/fiultra/THE%20WRITER'S%20HOUSE.html

Andre Jute

unread,
Aug 24, 2009, 6:55:21 PM8/24/09
to

I once caught out a fellow called Michael Lafevre, who claimed t have
a master's degree in politics from an Ivy League college, believing
that Gothenburg is in Austria... An American education is like a
roulette wheel: many, many, many parts are dead losses, with the rare
tiny pocket of a win. Looks increasingly like "jim beam" was
"educated" in one of the black holes of American education if he
cannot even distinguish between Ghent and Delft. He probably doesn't
even know they're in two different sovereign countries. What an idiot.

Andre Jute
"By definition, the presence of a cam tells you it's not 2-stroke."
-- "jim beam", internet ignoramus, proving his "competence"

Andre Jute

unread,
Aug 24, 2009, 6:59:15 PM8/24/09
to

Aw, for chrisesake, if the guy is connected with Ghent, even in one of
their down periods, he has a better education than any American
engineer. In fact, anyone who came through that class of German high
school called a gymnasium, and their equivalents in several other
continental countries (France, all the Benelux countries -- look them
up, fellers -- Switzerland, to name only the obvious ones) will be
better educated than any American engineer.

Andre Jute
Cosmopolitan

Andre Jute

unread,
Aug 24, 2009, 7:17:12 PM8/24/09
to

I am not planning to say much in this thread, though I actually wrote
a section on vibration damping in one of my books on automobile
design. This thread is too contaminated by the suspect sourcing and
interpretation of the data by that idiot blogger ever to straighten
out the facts in the presence of so many overblown egos.

However, I will say this. In advertising and marketing I acquired a
great deal of experience in judging the validity of statistical tests
on matters of taste. (And we should note, when you're spending tens of
millions of other people's money, you'd better get it right first
time. Deciding on product development and placement isn't some little
engineering game, it is serious business for big money stakes.) Dave
Luyckx's study is several steps removed from the uncertainties I
worked with, because reports of "comfort" can be tested by metering,
as he has done. Despite my initial suspicion, created by the
inadequate and inaccurate report of Dave's work, I think that his
multi-metered approach at least abstracts from the problem of what the
tires contribute, and in general shows promise for a way to test a
wide variety of marketing claims about vibration damping of frames of
various materials and constructions.

Any peanut gallery of underemployed clowns can find fault with any
study; nothing is ever good enough for people who do nothing but
criticize. But here is an instance of fieldwork that shows promise,
and we should welcome it constructively. I think these studies of Dave
Luyckx can only get better and better as they spiral in on a closer
and closer view of what actually happens in a frame.

Andre Jute
A little, a very little thought will suffice -- John Maynard Keynes
Visit Jute on Bicycles at
http://www.audio-talk.co.uk/fiultra/BICYCLE%20%26%20CYCLING.html

jim beam

unread,
Aug 24, 2009, 8:07:29 PM8/24/09
to
barbara cartland, the ridiculous 64-year old schizo narcissistic pervert
imposter bleated:

still wasting bandwidth on someone allegedly in your killfile andre?
what a fucking loser.

btw, the distance between ghent and delft is 74 miles.
http://www.distance-calculator.co.uk/distance-calculator.php?town1=Gent&town2=Delft&ref=no


that's a good deal shorter than the distance between you and mensa
membership.

http://home.comcast.net/~czell/densaapp.htm


jim beam

unread,
Aug 24, 2009, 8:08:23 PM8/24/09
to

ok, you got me there.

jim beam

unread,
Aug 24, 2009, 8:12:30 PM8/24/09
to

er, ghent is in belgium, not germany.


> called a gymnasium, and their equivalents in several other
> continental countries (France, all the Benelux countries -- look them
> up, fellers -- Switzerland, to name only the obvious ones) will be
> better educated than any American engineer.

in jutespeak, "educated at" = "failed to graduate from". how many
universities threw you out andre? two? three?

jim beam

unread,
Aug 24, 2009, 8:13:04 PM8/24/09
to

here's something to sort you out andre:
http://home.comcast.net/~czell/densaapp.htm

Jan Jolly

unread,
Aug 24, 2009, 9:59:24 PM8/24/09
to

Hye beamer dude, i'm curious. Is there anything good you can do in a
discussion about bike tech other than spur spite, anger and personal
attack. C'mon man, seriously. Go work in the movies. They need to
portray real world idiots. No one does it better than you.

jim beam

unread,
Aug 24, 2009, 10:59:21 PM8/24/09
to

hey jolly dude, i'm curious. what's it like to be such a hypocrite?

1. you show up here with some ignorant bullshit about "pea and princess
story".

2. then you take a swipe at what is for once an interesting contributor
with "Did a search for 'David Luyckx'" [your emphasis] because
apparently useful content isn't immediately apparent to you. then,
disappointed to find that this person may actually have credentials, you
make an utterly asinine comment about purpose, vis: "Why is someone from

Toyota involved in Museeuw's business."

3. then you get bent about me pointing out the obvious - that you're not
contributing anything tech, merely pissing and moaning.

so what is it with you? don't you like getting called out for what you
are? [rhetorical] maybe you could contribute something tech?
[unlikely based on your record so far.]

B

unread,
Aug 24, 2009, 11:58:33 PM8/24/09
to

Ofcourse

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