Handlebar vibration damping question

Phil said:

This post is actually in reference to a motorcycle, not a bicycle, but the
principles are the same.

My Honda CBR600 F2 is buzzy as hell from the engine (~7000rpms on the
highway) and it numbs my hands after 100 miles. I have considered putting
new Oury grips (my fav), attaching heavy barends, raising the final drive
ratio to lower rpms, and this thing:

http://www.bontrager.com/Road/Parts_and_Accessories/Handlebar_Accessories/22929.php

Obviously this is a "tuned" (yeah, right) damper system for a typical road
handlebar. How full of fluff is it? Has anyone here tried them and noticed
any difference? I think the ID for most motorcycle handlebars and bicycle
handlebars are roughly 3/4" so this should fit.

Theoretically, I could derive the cantilever beam k constant equation and
get omega n, and then determine a tuned damping system with a specific
weight, but I'm done with that class and I'd probably get some barend weight
of several kilograms or something, so I'm just going to have to skip the
theoretical [censored]. I'd really love to know if anyone here has empirical
results on their bicycle, or even any vibration damping suggestions on their
own motorcycle.

--
Phil, Squid-in-Training

What about filling the bar with some construction foam and sand or BB's
or something? I seem to recall a bar full of BB's being used by a guy I
knew once. (The guys behind you might not appreciate a bar-load of BB's
spilling out on the road if the end cap fell out, thus the foam) Or get
some ape-hangers, so your whole arms are numb, and thus you won't be
bothered by numb hands!

If you did figure it mathematically, you'd also have to figure in the
mass of your hands, and that might be difficult.

Joseph

Phil said:

This post is actually in reference to a motorcycle, not a bicycle, but the
principles are the same.

My Honda CBR600 F2 is buzzy as hell from the engine (~7000rpms on the
highway) and it numbs my hands after 100 miles. I have considered putting
new Oury grips (my fav), attaching heavy barends, raising the final drive
ratio to lower rpms, and this thing:

http://www.bontrager.com/Road/Parts_and_Accessories/Handlebar_Accessories/22929.php

Obviously this is a "tuned" (yeah, right) damper system for a typical road
handlebar. How full of fluff is it? Has anyone here tried them and noticed
any difference? I think the ID for most motorcycle handlebars and bicycle
handlebars are roughly 3/4" so this should fit.

Theoretically, I could derive the cantilever beam k constant equation and
get omega n, and then determine a tuned damping system with a specific
weight, but I'm done with that class and I'd probably get some barend weight
of several kilograms or something, so I'm just going to have to skip the
theoretical [censored]. I'd really love to know if anyone here has empirical
results on their bicycle, or even any vibration damping suggestions on their
own motorcycle.

--
Phil, Squid-in-Training

Or buy a BMW inline 4 cylinder.

Squid-in-Training said:

My Honda CBR600 F2 is buzzy as hell from the engine (~7000rpms on the
highway) and it numbs my hands after 100 miles. I have considered putting
new Oury grips (my fav), attaching heavy barends, raising the final drive
ratio to lower rpms, and this thing:

Have you checked that the bike still has its original bar-end weights? An
F2 must be over 12 years old now, and all sorts of things could have been
done to it. On inline four is always going to have some vibration, but
it shouldn't be so bad as to number the hands. Or get a VFR, I've done
over 700 miles in a day on my 750 with no problems for hands or backside.

Mike

Phil Lee said:

This post is actually in reference to a motorcycle, not a bicycle,
but the principles are the same.

Quoted message said:

My Honda CBR600 F2 is buzzy as hell from the engine (~7000rpm on the
highway) and it numbs my hands after 100 miles. I have considered
putting new Oury grips (my fav), attaching heavy bar-ends, raising
the final drive ratio to lower rpm, and this thing:

http://tinyurl.com/o2wnf

Quoted message said:

Obviously this is a "tuned" (yeah, right) damper system for a
typical road handlebar. How full of fluff is it? Has anyone here
tried them and noticed any difference? I think the ID for most
motorcycle handlebars and bicycle handlebars are roughly 3/4" so
this should fit.

I saw the promotion they do for these things and if that isn't a dead
giveaway I don't know what is. They take a bare aluminum handlebar and
drop it on the concrete floor from about 4" and hear it clang. Then
they put the Bzzzkill-Harmonic-Damper in the bar ends and repeat the
test with a dull thud.

Well... if you took my bars with bar tape on them you would get even
less of a thud even if you struck the untaped portion of the bar.
What is even more telling is that the mass inside these bright orange
rubber suspensions is aluminum instead of steel or lead. I'll bet if
they used Magnesium, or even Beryllium they could save even more
weight. Of course, mass is part of the damping equation but forget
that.

Quoted message said:

Theoretically, I could derive the cantilever beam k constant
equation and get omega n, and then determine a tuned damping system
with a specific weight, but I'm done with that class and I'd
probably get some bar-end weight of several kilograms or something,
so I'm just going to have to skip the theoretical [censored]. I'd really
love to know if anyone here has empirical results on their bicycle,
or even any vibration damping suggestions on their own motorcycle.

I'm sure we can get some testimonials from satisfied users, if they
dare to rise to the occasion. I have a pair that were given to me by
by a bicycle shop. Great conversation pieces!

Jobst Brandt

Mororcycle cops who ride Harleys use bars full of silicon, and yes it
works. I've ridden a Harley with silicon in the bars and the change is
drastic, motorcycle cops who are on their cycles all day swear by it,
they all say they wouldn't be able to ride all day without it.
-Tim

Quoted message said:

Mororcycle cops who ride Harleys use bars full of silicon, and yes it
works. I've ridden a Harley with silicon in the bars and the change is
drastic, motorcycle cops who are on their cycles all day swear by it,
they all say they wouldn't be able to ride all day without it.

Amorphous silica or quartz?

--
Tom Sherman

Johnny Sunset aka Tom Sherman said:

Quoted message said:

Mororcycle cops who ride Harleys use bars full of silicon, and yes it
works. I've ridden a Harley with silicon in the bars and the change is
drastic, motorcycle cops who are on their cycles all day swear by it,
they all say they wouldn't be able to ride all day without it.

Amorphous silica or quartz?

He said "silicon", so obviously he means monocrystalline elemental
silicon, as used in semiconductors. Seems a bit strange since it's so
much harder and stiffer than steel.

Chalo

Chalo said:

Johnny Sunset aka Tom Sherman said:

Quoted message said:

Mororcycle cops who ride Harleys use bars full of silicon, and yes
it works. I've ridden a Harley with silicon in the bars and the
change is drastic, motorcycle cops who are on their cycles all day
swear by it, they all say they wouldn't be able to ride all day
without it.

Amorphous silica or quartz?

He said "silicon", so obviously he means monocrystalline elemental
silicon, as used in semiconductors. Seems a bit strange since it's so
much harder and stiffer than steel.

Tim meant silicone caulking. I neglected to do the obligatory Google search
before asking the newsgroup.

Apparently the difference is to add fish weights, seal them in with
silicone, and voilà, less vibration.

--
Phil, Squid-in-Training

Chalo Colina said:

Johnny Sunset aka Tom Sherman said:

Quoted message said:

Mororcycle cops who ride Harleys use bars full of silicon, and yes it
works. I've ridden a Harley with silicon in the bars and the change is
drastic, motorcycle cops who are on their cycles all day swear by it,
they all say they wouldn't be able to ride all day without it.

Amorphous silica or quartz?

He said "silicon", so obviously he means monocrystalline elemental
silicon, as used in semiconductors. Seems a bit strange since it's so
much harder and stiffer than steel.

This reference shows elemental silicon only being about 55% as stiff as
steel (112 versus 205 GPa):
<http://www.matweb.com/search/SpecificMaterial.asp?bassnum=AMESi00>.

--
Tom Sherman

Phil said:

Chalo said:

He said "silicon", so obviously he means monocrystalline elemental
silicon, as used in semiconductors. Seems a bit strange since it's so
much harder and stiffer than steel.

Tim meant silicone caulking. I neglected to do the obligatory Google search
before asking the newsgroup.

Apparently the difference is to add fish weights, seal them in with
silicone, and voilà, less vibration.

Sorry. I left out the smiley since it seemed unnecessary.

I find some folks's unwillingness to distinguish between silicone and
silicon pretty amusing. It's like not distinguishing between sulfur
and sulfa drugs, or between carbon and carbohydrates. Once you've seen
examples of both, it would be tough to get them confused with each
other.

Chalo

Johnny Sunset aka Tom Sherman said:

Chalo Colina said:

He said "silicon", so obviously he means monocrystalline elemental
silicon, as used in semiconductors. Seems a bit strange since it's so
much harder and stiffer than steel.

This reference shows elemental silicon only being about 55% as stiff as
steel (112 versus 205 GPa):
<http://www.matweb.com/search/SpecificMaterial.asp?bassnum=AMESi00>.

Right you are. Monocrystalline silicon is a bit stiffer than that
(though it's variable based on subtleties of composition-- I've found
numbers from 1.30 to 1.88 GPa). I guess it's always seemed stiffer
than steel to me because it _sounds_ so much stiffer, with more than
2/3 the modulus and less than 1/3 the density of steel.

Chalo

Chalo said:

Johnny Sunset aka Tom Sherman said:

Chalo Colina said:

He said "silicon", so obviously he means monocrystalline elemental
silicon, as used in semiconductors. Seems a bit strange since it's so
much harder and stiffer than steel.

This reference shows elemental silicon only being about 55% as stiff as
steel (112 versus 205 GPa):
<http://www.matweb.com/search/SpecificMaterial.asp?bassnum=AMESi00>.

Right you are. Monocrystalline silicon is a bit stiffer than that
(though it's variable based on subtleties of composition-- I've found
numbers from 1.30 to 1.88 GPa). I guess it's always seemed stiffer
than steel to me because it _sounds_ so much stiffer, with more than
2/3 the modulus and less than 1/3 the density of steel.

Chalo

ok, so when are you two comedians finally going to put the guy out of
his misery and point out that he means "silicone", the elastomer, not
"silicon" the semi-metal? you've had your laugh. r.b.t being what it
is, some people will think you're serious. then it'll be repeated. and
repetition means it'll be taken as true. next thing we know, we'll be
citing yield as modulus and getting into fearful kerfuffles about
rolling resistance. be careful.

"jim beam" (who?) anonymously snipes:

Quoted message said:

Chalo said:

Johnny Sunset aka Tom Sherman said:

Chalo Colina wrote:

>He said "silicon", so obviously he means monocrystalline elemental
>silicon, as used in semiconductors. Seems a bit strange since it's so
>much harder and stiffer than steel.

This reference shows elemental silicon only being about 55% as stiff as
steel (112 versus 205 GPa):
<http://www.matweb.com/search/SpecificMaterial.asp?bassnum=AMESi00>.

Right you are. Monocrystalline silicon is a bit stiffer than that
(though it's variable based on subtleties of composition-- I've found
numbers from 1.30 to 1.88 GPa). I guess it's always seemed stiffer
than steel to me because it _sounds_ so much stiffer, with more than
2/3 the modulus and less than 1/3 the density of steel.

Chalo

ok, so when are you two comedians finally going to put the guy out of
his misery and point out that he means "silicone", the elastomer, not
"silicon" the semi-metal? you've had your laugh. r.b.t being what it
is, some people will think you're serious. then it'll be repeated. and
repetition means it'll be taken as true. next thing we know, we'll be
citing yield as modulus and getting into fearful kerfuffles about
rolling resistance. be careful.

Silicone as in "Silicone Valley", the place where the female hominids
have artificially oversized mammary glands? 😉

--
Tom Sherman

Well I could have spelled it right, but it looks like you got the idea.
-Tim

Johnny Sunset aka Tom Sherman said:

"jim beam" (who?) anonymously snipes:

Quoted message said:

Chalo said:

Johnny Sunset aka Tom Sherman wrote:

>Chalo Colina wrote:
>
>
>>He said "silicon", so obviously he means monocrystalline elemental
>>silicon, as used in semiconductors. Seems a bit strange since it's so
>>much harder and stiffer than steel.
>
>This reference shows elemental silicon only being about 55% as stiff as
>steel (112 versus 205 GPa):
><http://www.matweb.com/search/SpecificMaterial.asp?bassnum=AMESi00>.

Right you are. Monocrystalline silicon is a bit stiffer than that
(though it's variable based on subtleties of composition-- I've found
numbers from 1.30 to 1.88 GPa). I guess it's always seemed stiffer
than steel to me because it _sounds_ so much stiffer, with more than
2/3 the modulus and less than 1/3 the density of steel.

Chalo

ok, so when are you two comedians finally going to put the guy out of
his misery and point out that he means "silicone", the elastomer, not
"silicon" the semi-metal? you've had your laugh. r.b.t being what it
is, some people will think you're serious. then it'll be repeated. and
repetition means it'll be taken as true. next thing we know, we'll be
citing yield as modulus and getting into fearful kerfuffles about
rolling resistance. be careful.

Silicone as in "Silicone Valley", the place where the female hominids
have artificially oversized mammary glands? 😉

you're referring to 33.93N 118.40W i believe. very little elastomer at
my coordinates.

[email hidden] wrote (to someone about something):

Quoted message said:

Well I could have spelled it right, but it looks like you got the
idea. -Tim

"What are you talking about?"

Bill "for Michael Press" S.