Rear wheel spoke tension ratio
gig...@gmail.com
Jobst Brandt's book indicates that the ratio for an eight speed hub is
about 2.5:1.
As an example, I am using Spocalc. Velocity Deep V 700C rear rim with
a Dura Ace 10sp hub, and its telling the the left bracing angle is
6.5º and the right bracing angle is 4.6º.
Doing a simple vector analysis and using a value of 100 for the left
side tension, I'm coming up with 141 as the right side tension. I'm
getting this from: 100 sin 6.5º = 11.32 (left side lateral component)
141.15 sin 4.6º = 11.32(right side lateral component)
The values of 100 and 141 are the tension values of the spokes, so it
seems to me that the actual ratio is 141/100 = 1.41:1
Where does Jobst's ratio of 2.5:1 come from? What am I missing here?
Thanks,
Greg
jobst....@stanfordalumni.org
> I'm a little confused on the tension ratio of a dished rear wheel.
> Jobst Brandt's book indicates that the ratio for an eight speed hub
> is about 2.5:1.
> As an example, I am using Spocalc. Velocity Deep V 700C rear rim
> with a Dura Ace 10sp hub, and it's telling the the left bracing
> angle is 6.5º and the right bracing angle is 4.6º.
> Doing a simple vector analysis and using a value of 100 for the left
> side tension, I'm coming up with 141 as the right side tension. I'm
> getting this from: 100 sin 6.5º = 11.32 (left side lateral
> component) 141.15 sin 4.6º = 11.32(right side lateral component)
> The values of 100 and 141 are the tension values of the spokes, so
> it seems to me that the actual ratio is 141/100 = 1.41:1
Yes (tan(6.5)/tan(4.6)) = 1.416.
> Where does Jobst's ratio of 2.5:1 come from? What am I missing
> here?
What flange spacing are you using and what is the offset? The values
in the book were derived from Campagnolo RECORD hubs of the day.
These were initially designed for 4-speed gear clusters. Like the
ones you see in the graphic figures and on the cover. This was not
intended to be a definitive value but rather an example of how
strongly more and more sprockets affect wheel reliability.
Jobst Brandt
carl...@comcast.net
Dear Greg,
The differences in tension are due to the differences in the spoke
angles used for calculations.
On page 43 of the 1st edition of "The Bicycle Wheel," the rear spoke
left/right angles are shown as 7.3 versus 3.5 degrees.
7.3 vs 3.5 = ~2.1 tension ratio <--Jobst's 6-speed example
6.5 vs 4.6 = ~1.4 tension ratio <--your example deep v 10-speed
Jobst's example works out to ~2.1 to 1, while your example works out
to ~1.4 to 1:
tan(7.3)/tan(3.5) = 0.1281/0.06116 = ~2.093
tan(6.5)/tan(4.6) = 0.1139/0.08046 = ~1.416
In Jobst's example, the left spokes are angled about twice as much as
his right spokes.
But your left spokes are angled only about 50% more than your right
spokes.
With such small angles, heads-in and heads-out may confuse things even
more. (Jobst's diagram shows spokes laced heads-out, which makes the
angles as steep and small as possible.)
It's darned interesting if the old 6-speed spokes were 7.3 x 3.5
degrees, while modern 10-speed spokes are 6.5 x 4.6 degrees--it
suggests that the manufacturers reduced the spoke angles in order to
reduce the necessary tension differences.
But it could just be that some tiny angles were measured differently
or incorrectly.
Cheers,
Carl Fogel
rruff
> Where does Jobst's ratio of 2.5:1 come from? What am I missing here?
The flange offsets for a Dura Ace 7800 hub are 18.5mm and 34.5mm,
so... I think your angles are wrong. So if they are cross-laced the
same on both sides, the tension ratio will be ~ 34.5/18.5 = 1.86.
P. Chisholm
It's great you are thinking so hard on this but if you DO build a
wheel, please don't use 100 kgf on the left, or non drive side. Use
100 kgf on the right, drive side.
Peter-wheelbuilder.
Ken Freeman
Excellent comments, Carl! I would think the angles are accurate
enough that the surprising difference is real. They are small, but
they can be calculated accurately from hub and flange dimensions, and
there's really no difficulty in measuring hub and flange dimensions
accurately, with a vernier, dial, or digital caliper.
If the angles are good, the only explanation is that in newer hubs the
non-drive side flange has been moved inboard to compensate the
disparity. or am I missing something?
Ken Freeman
jobst....@stanfordalumni.org
> Excellent comments, Carl! I would think the angles are accurate
> enough that the surprising difference is real. They are small, but
> they can be calculated accurately from hub and flange dimensions,
> and there's really no difficulty in measuring hub and flange
> dimensions accurately, with a vernier, dial, or digital caliper.
> If the angles are good, the only explanation is that in newer hubs
> the non-drive side flange has been moved inboard to compensate the
> disparity. or am I missing something?
... Not to overlook the offset for gear clusters, the feature that
made rear hubs so laterally weak with have lopsided spoke tension.
Manufacturers just moved the flanges closer together to reduce the
angle. They had to, with so few spokes that require higher tension
than formerly, so the right side with it's few spokes, carries nearly
all the load, the left side spokes easily becoming slack in use...
SpokePrep to the rescue!
Jobst Brandt
russell...@yahoo.com
>
> - Show quoted text -
I've never used a tension meter when building wheels. But the
mechanics of wheel building would likely prevent you from using such a
high tension on the non drive side. If you did, the rim would be
rubbing the non drive chainstays and it would be kind of obvious
something was wrong. You would try to compensate, re dish the wheel,
by cranking the drive side tension up to 200 or whatever, and it would
not work. Nipples would break. Threads would strip. Etc.
jobst....@stanfordalumni.org
>>> I'm a little confused on the tension ratio of a dished rear wheel.
>>> Jobst Brandt's book indicates that the ratio for an eight speed
>>> hub is about 2.5:1.
>>> As an example, I am using Spocalc. Velocity Deep V 700C rear rim
>>> with a Dura Ace 10sp hub, and its telling the the left bracing
>>> angle is 6.5º and the right bracing angle is 4.6º.
>>> Doing a simple vector analysis and using a value of 100 for the
>>> left side tension, I'm coming up with 141 as the right side
>>> tension. I'm getting this from: 100 sin 6.5º = 11.32 (left side
>>> lateral component) 141.15 sin 4.6º = 11.32(right side lateral
>>> component)
>>> The values of 100 and 141 are the tension values of the spokes, so
>>> it seems to me that the actual ratio is 141/100 = 1.41:1
>>> Where does Jobst's ratio of 2.5:1 come from? What am I missing
>>> here?
>> It's great you are thinking so hard on this but if you DO build a
>> wheel, please don't use 100 kgf on the left, or non drive
>> side. Use 100 kgf on the right, drive side.
> I've never used a tension meter when building wheels. But the
> mechanics of wheel building would likely prevent you from using such
> a high tension on the non drive side. If you did, the rim would be
> rubbing the non drive chainstays and it would be kind of obvious
> something was wrong. You would try to compensate, re dish the
> wheel, by cranking the drive side tension up to 200 or whatever, and
> it would not work. Nipples would break. Threads would strip. Etc.
Under Etc. are where the real problems could be. Brass nipples would
neither break nor strip threads. Using a tensiometer is for assessing
whether the spoke complement is at a desired tension, not to measure
individual spokes for trueness. Because most rims merely have eyelets
instead of eyelets with sockets that distribute load to inside and
outside walls of the rim, spoke holes breaking out is the main
problem.
Old socketed rims (formerly most rims) would no longer stay true if
spoked too tightly, deforming into a slight "pretzel", something that
was readily correctable by reducing tension a little.
Jobst Brandt
Nick L Plate
Or just avoid ridiculous high tension by using thicker spokes.
Mike Jacoubowsky
If the angles are good, the only explanation is that in newer hubs the
non-drive side flange has been moved inboard to compensate the
disparity. or am I missing something?
Ken Freeman
============
You've got it exactly right. The advantages of having flanges further
apart are negated by the disadvantage of having too much load on the
drive-side spokes, causing rim failure (cracks at the nipple/rim
interface). I'm not sure of the limits though; obviously, there's no
lateral strength at all if spokes from each side come straight up from
the middle of the flange. How narrow can you safely go?
--Mike Jacoubowsky
Chain Reaction Bicycles
www.ChainReaction.com
Redwood City & Los Altos, CA USA
"Ken Freeman" <kenfre...@gmail.com> wrote in message
news:6fac6eb3-61d8-4b82...@k38g2000yqh.googlegroups.com...
russell...@yahoo.com
I built a couple wheels with Sapim brass nipples recently, and I have
to report I twisted them such that the surface gripped by the spoke
nipple is twisted around. Brass nipples are far from impervious.
Using a tensiometer is for assessing
> whether the spoke complement is at a desired tension, not to measure
> individual spokes for trueness. Because most rims merely have eyelets
> instead of eyelets with sockets that distribute load to inside and
> outside walls of the rim, spoke holes breaking out is the main
> problem.
>
> Old socketed rims (formerly most rims) would no longer stay true if
> spoked too tightly, deforming into a slight "pretzel", something that
> was readily correctable by reducing tension a little.
>
> Jobst Brandt- Hide quoted text -
carl...@comcast.net
>I built a couple wheels with Sapim brass nipples recently, and I have
>to report I twisted them such that the surface gripped by the spoke
>nipple is twisted around. Brass nipples are far from impervious.
Dear Russell,
If you still have one, a photo would be interesting.
Cheers,
Carl Fogel
jobst....@stanfordalumni.org
> Or just avoid ridiculous high tension by using thicker spokes.
What do stiffer spokes do to prevent slack spokes when the rim
deflects under load beside becoming slack at even smaller rim
deflection. To prevent spokes from becoming slack is why they are
made as thin as they are, swaged to a smaller cross section at midspan
to be more elastic to absorb rim deflections. This was done not to
save weight, but rather to build more durable wheels.
I see it coming... More Spoke Prep! Sweep it under the "glue rug".
Jobst Brandt
russell...@yahoo.com
> On Wed, 22 Apr 2009 11:57:33 -0700 (PDT), "russellseat...@yahoo.com"
>
> <russellseat...@yahoo.com> wrote:
> >I built a couple wheels with Sapim brass nipples recently, and I have
> >to report I twisted them such that the surface gripped by the spoke
> >nipple is twisted around. Brass nipples are far from impervious.
>
> Dear Russell,
>
> If you still have one, a photo would be interesting.
>
> Cheers,
>
> Carl Fogel
I'm using the twisted Sapim nipples on my new single speed bike. But
I am not terribly modern and have no camera available. I'll see if a
friend can take a picture and send me the picture.
Nick L Plate
> Trevor Jeffrey wrote:
>>JB wrote
> >> Old socketed rims (formerly most rims) would no longer stay true if
> >> spoked too tightly, deforming into a slight "pretzel", something
> >> that was readily correctable by reducing tension a little.
> > Or just avoid ridiculous high tension by using thicker spokes.
>
> What do stiffer spokes do to prevent slack spokes when the rim
> deflects under load beside becoming slack at even smaller rim
> deflection. To prevent spokes from becoming slack is why they are
> made as thin as they are, swaged to a smaller cross section at midspan
> to be more elastic to absorb rim deflections. This was done not to
> save weight, but rather to build more durable wheels.
YOU said;
"Old socketed rims (formerly most rims) would no longer stay true if
spoked too tightly, deforming into a slight "pretzel", something that
was readily correctable by reducing tension a little."
I said;
"Or just avoid ridiculous high tension by using thicker spokes."
I have previously posted information on my wheel build technique, the
spoke tension at 170lbf is sufficient to maintain a stiff wheel
without any spoke going slack at any time. So your premise that
thinner spokes are needed to prevent slack spokes is false. The
higher tensions associated with overtly thin spokes make for a less
durable wheel. High spoke tension induces buckling, rim pull through,
split hubs and folding. The lack of stability in the wheel with too
thin spokes is problematic when climbing, sprinting, cornering or
decending. I believe there may also be som basic inefficiencies due
to a low stiffness wheel.
jobst....@stanfordalumni.org
You needn't confess your sins to RBT, just mend your ways. The
subject has come up here often enough. A brass spoke nipple can twist
off any spoke it engages even with a parallel jawed spoke wrench.
Rounding and twisting spoke nipples is caused by not lubricating the
interface between spoke nipple and rim. Friction between spoke nipple
and rim is four times greater (diameter) than dry spoke threads can
produce and about twice that over lubricated spoke threads. Use
hypoid gear lubricant for that by dipping treads of an entire set of
spokes into 1mm deep oil in a flat bottom can, then after lacing and
taking out spoke slack, add a drop of motor oil at each spoke
nipple/rim eyelet.
>> Using a tensiometer is for assessing whether the spoke complement
>> is at a desired tension, not to measure individual spokes for
>> trueness. Because most rims merely have eyelets instead of eyelets
>> with sockets that distribute load to inside and outside walls of
>> the rim, spoke holes breaking out is the main problem.
>> Old socketed rims (formerly most rims) would no longer stay true if
>> spoked too tightly, deforming into a slight "pretzel", something
>> that was readily correctable by reducing tension a little.
You might have gain absolution for your sins, but complaints from
users such as you have recently burdened us with spoke wrenches that
cannot be slipped onto spoke nipples as an open end wrench but rather
as a slotted socket making the job too clumsy for fast work.
http://www.sheldonbrown.com/var/pages/var0036.html
Item 51 was the worlds best hardened steel spoke wrench until so many
spoke nipples got rounded by lack of lubrication. Now one end is a
slotted socket:
http://www.vartools.com/fr/fiche_produit.php?id=484&shop=0&pro=0
...as if that did any good.
Jobst Brandt
Nick L Plate
> Russell Seaton1 wrote:
> > I built a couple wheels with Sapim brass nipples recently, and I
> > have to report I twisted them such that the surface gripped by the
> > spoke nipple is twisted around. Brass nipples are far from
> > impervious.
>
> You needn't confess your sins to RBT, just mend your ways. The
> subject has come up here often enough. A brass spoke nipple can twist
> off any spoke it engages even with a parallel jawed spoke wrench.
> Rounding and twisting spoke nipples is caused by not lubricating the
> interface between spoke nipple and rim. Friction between spoke nipple
> and rim is four times greater (diameter) than dry spoke threads can
> produce and about twice that over lubricated spoke threads. Use
> hypoid gear lubricant for that by dipping treads of an entire set of
> spokes into 1mm deep oil in a flat bottom can, then after lacing and
> taking out spoke slack, add a drop of motor oil at each spoke
> nipple/rim eyelet.
Unnecessary kerfaffle from someone who abhors the very idea of spoke
prep. It's the same process, just use linseed oil. Or dont use
anything, and load the rim where you adjust the nipple. By doing this
you should realise that there is a requirement for a retaining medium
to prevent nipple unwind.
Nick L Plate
> Wed, 22 Apr 2009 13:37:07 -0700 (PDT), Nick L Plate:
> That's the wrong way round. Thinner spokes allow lower tension on critical
> wheels. At the same tension level a thinner spoke allows more deformation
> (becoming shorter), bevore it gets slack. This allows to distribute the
> result of a local deformation of the rim over more spokes.
Taken to conclusion, the thinnest spokes, nothing, would need zero
tension to support an infinite mass. This clearly, in my eyes but not
fot the jobstian fellowship, cannot be done. Spokes do not need to be
cheesewire thin for the load to be distributed. It is because the
spokes can only support tension that they are able to distribute the
load in the way a compression spoked wheel cannot. Because the spokes
are in tension, they cannot give through buckling. It is possible to
minimise spoke size for strength criteria, but it is better to specify
for stiffness rather than strength.
Nick L Plate
> Of course. But the usual discussion is to choose between normal streight
> 2mm spokes, thick 2,3mm spokes, DD spokes reduced to 1,8mm in the middle.
> Experience shows, that it is easier to build a long-lasting dished tandem
> wheel with 1,8mm DD spokes than with 2mm spokes. 1.5mm DD race spokes
> might be on the "too thin" side - alone for the reason of ugly spoke
> wind-up during wheelbuilding.
2mm or 14swg is thick. 1.8mm or 15swg is normal. 36x15swg makes for
a robust rear wheel with a 400g rim
>
> >This clearly, in my eyes but not
> >fot the jobstian fellowship, cannot be done. Spokes do not need to be
> >cheesewire thin for the load to be distributed.
>
> Depends on the load, on the stiffness of the rim and on the number of
> spokes.
>
> > It is because the
> >spokes can only support tension that they are able to distribute the
> >load in the way a compression spoked wheel cannot. Because the spokes
> >are in tension, they cannot give through buckling. It is possible to
> >minimise spoke size for strength criteria, but it is better to specify
> >for stiffness rather than strength.
>
> "Wheel stiffness" on its own isn't of much help. The wheel has to be
> durable - and a stiff rim will reduce the dynamic force range in the
> spokes.
The use of an aluminium rim with steel spokes and a pneumatic tyre
(all correctly specified) are what makes a bike wheel durable. Only
if the wheel is built wrong is its durability compromised. Wheel
stiffness is the only comparable measure one can make without
destructive testing to determine failure rate. And this failure rate
will only be for a particular load and may not reflect actual usage
anyway.
_
> Wed, 22 Apr 2009 15:03:52 -0700 (PDT), Nick L Plate:
>
>>On 22 Apr, 22:33, Andreas Oehler <andreas.oeh...@gmx.de> wrote:
>>> Wed, 22 Apr 2009 13:37:07 -0700 (PDT), Nick L Plate:
>>
>>> That's the wrong way round. Thinner spokes allow lower tension on critical
>>> wheels. At the same tension level a thinner spoke allows more deformation
>>> (becoming shorter), bevore it gets slack. This allows to distribute the
>>> result of a local deformation of the rim over more spokes.
>>
>>Taken to conclusion, the thinnest spokes, nothing, would need zero
>>tension to support an infinite mass.
>
> Of course. But the usual discussion is to choose between normal streight
> 2mm spokes, thick 2,3mm spokes, DD spokes reduced to 1,8mm in the middle.
> Experience shows, that it is easier to build a long-lasting dished tandem
> wheel with 1,8mm DD spokes than with 2mm spokes.
Not just experience shows that; but also an understanding of the forces and
properties of materials...
...but this is a fellow who asserts that the majority of cyclists have
exceeded 60mph; things might be a bit 'different' in his world...
Brian Huntley
>
> You needn't confess your sins to RBT, just mend your ways. The
> subject has come up here often enough. A brass spoke nipple can twist
> off any spoke it engages even with a parallel jawed spoke wrench.
> Rounding and twisting spoke nipples is caused by not lubricating the
> interface between spoke nipple and rim. Friction between spoke nipple
> and rim is four times greater (diameter) than dry spoke threads can
> produce and about twice that over lubricated spoke threads. Use
> hypoid gear lubricant for that by dipping treads of an entire set of
> spokes into 1mm deep oil in a flat bottom can, then after lacing and
> taking out spoke slack, add a drop of motor oil at each spoke
> nipple/rim eyelet.
I'm a little confused by this, but very interested due to a rear rim
change I did recently that didn't work as well as I'd hoped the first
time around.
If the biggest issue (by a factor of 2 or 4, as you say) is the nipple-
to-rim interface, why should the spoke-to-nipple interface be an
issue? I was paranoid about lubing the threads too much after all the
fud about using a binder like linseed oil, so skipped that on my used
spokes. Was that a major error? It *was* hard to bring the wheel up to
what seemed like a reasonably tight tension, I'll admit.
Should I consider re-doing the wheel one nipple (with lube) at a time,
or am I probably okay? The bike is used for daily urban commuting, and
about a week of loaded touring every summer.
Nick L Plate
Ride over a cobbled street with your load, and if it all seems solid
enough at 16mph, then its good. The bottom spoke should stay 'in
tension' for the predicted maximum load, that's all.
jobst....@stanfordalumni.org
>> You needn't confess your sins to RBT, just mend your ways. The
>> subject has come up here often enough. A brass spoke nipple can
>> twist off any spoke it engages even with a parallel jawed spoke
>> wrench. Rounding and twisting spoke nipples is caused by not
>> lubricating the interface between spoke nipple and rim. Friction
>> between spoke nipple and rim is four times greater (diameter) than
>> dry spoke threads can produce and about twice that over lubricated
>> spoke threads. Use hypoid gear lubricant for that by dipping
>> treads of an entire set of spokes into 1mm deep oil in a flat
>> bottom can, then after lacing and taking out spoke slack, add a
>> drop of motor oil at each spoke nipple/rim eyelet.
> I'm a little confused by this, but very interested due to a rear rim
> change I did recently that didn't work as well as I'd hoped the
> first time around.
> If the biggest issue (by a factor of 2 or 4, as you say) is the
> nipple- to-rim interface, why should the spoke-to-nipple interface
> be an issue?
Make that 4 and 2x4 times as much. For spoke nipples to unscrew
spokes must become slack consistently in use. It is not lubrication
that makes spoke nipples unscrew. I think you might peruse "the
Bicycle Wheel" to understand what makes spoked wheels survive or fail.
http://www.avocet.com/wheelbook/wheelbook.html
> I was paranoid about lubing the threads too much after all the fud
> about using a binder like linseed oil, so skipped that on my used
> spokes. Was that a major error? It *was* hard to bring the wheel
> up to what seemed like a reasonably tight tension, I'll admit.
Thread glues were invented to mask too loosely spoked wheels. Most
machine built wheels could not be made properly tight by the machine
because spoke twist prevented 1/4 turn adjustments so the machine went
into endless loops of up-a-quarter down-a-quarter adjustments that
produced no change.
I discovered this many years ago while watching a Holland Mechanics
machine, the first one Wheelsmith acquired. It was then that Rick
Hjertberg came up with Spoke Prep to cover for loosely spoked wheels.
I've talked at length with Holland Mechanics and BMD, makers of wheel
building machines, about a simple modification that would enable their
machines to build at any desired higher tension than is presently
possible.
> Should I consider re-doing the wheel one nipple (with lube) at a
> time, or am I probably OK? The bike is used for daily urban
> commuting, and about a week of loaded touring every summer.
Just add a drop of oil at the spoke nipple/eyelet and spoke/nipple
interfaces. It will wick in to where it is needed and you will find
spoke wrench torque4 greatly reduced. Get the book. It goes into
adequate detail on these issues.
Jobst Brandt
Nick L Plate
For spoke nipples to unscrew
> spokes must become slack consistently in use.
No, they only need to slacken, not become slack, vibration is what
turns the nipple not slack spokes.
It is not lubrication
> that makes spoke nipples unscrew. I think you might peruse "the
> 13icicle Melee" to understand what makes spoked wheels survive or fail.
>
> http://www.avocet.com/wheelbcok/wheelbock.html
The perfect example of how not to build a bike wheel. A major failing
of the author is being unable to understand that the greater stretch
of a thinner spoke produces a weaker wheel. He also fails to address
the reason for spoke failure at the elbow, somehow attributing some
magical change in the spoke which can only be expelled with the magic
potion and chant. Spokes fail at the elbow because of in service
bending, simple. Good spoke alignment during installation prevents
this bending and not only prevents spoke failure but also makes for a
stiffer and stronger wheel which doesn't suffer from rim failure or
buckling, a major problem for highly tensioned spoked wheels of which
JB maintains is the only waty to build. His complaints of raised rim
labels and a shimmying bike are due to him being unable to make a
wheel stiff enough for his own use.
> Thread glues were invented to mask too loosely spoked wheel.
That like linseed oil? Who "invented" linseed oil? Thread glues were
"invented" to fill a marketing niche, just about any gum, paste or wax
will do if you cant bear to use LINSEED oil.
> Most
> machine built wheels could not be made properly tight by the machine
> because spoke twist prevented 1/4 turn adjustments so the machine went
> into endless loops of up-a-quarter down-a-quarter adjustments that
> produced no change.
Just like a handbuilt wheel, this usually means the spokes are tight
enough. The wheel will be stiff as long as the spokes are correctly
installed to reduce in-service bending(the cause of spoke elbow
failure).
> I discovered this many years ago while watching a Holland Mechanics
> machine, the first one Wheelsmith acquired. It was then that Rick
> Hjertberg came up with Spoke Prep to cover for loosely spoked wheels.
A sensible person of an engineering bent would have deduced more, that
perhaps they dont need to be any tighter.
>
> I've talked at length with Holland Mechanics and BMD, makers of wheel
> building machines, about a simple modification that would enable their
> machines to build at any desired higher tension than is presently
> possible.
Bully for you.
> > Should I consider re-doing the wheel one nipple (with lube) at a
> > time, or am I probably OK? The bike is used for daily urban
> > commuting, and about a week of loaded touring every summer.
>
> Just add a drop of oil at the spoke nipple/eyelet and spoke/nipple
> interfaces.
If you feel you must, use linseed, or beeswax(nice)(heat it), it
prevents nipple unwind.
It will wick in to where it is needed and you will find
> spoke wrench torque4 greatly reduced. Get the book. It goes into
> adequate detail on these issues.
Don't bother , I've covered it.
jim beam
> Wed, 22 Apr 2009 13:37:07 -0700 (PDT), Nick L Plate:
>
>> "Old socketed rims (formerly most rims) would no longer stay true if
>> spoked too tightly, deforming into a slight "pretzel", something that
>> was readily correctable by reducing tension a little."
>>
>> I said;
>> "Or just avoid ridiculous high tension by using thicker spokes."
>
> wheels.
at the expense of stiffness. that may have been a fudge on old
un-dished wheels, but on highly dished wheels like we have today, that
doesn't work.
> At the same tension level a thinner spoke allows more deformation
> (becoming shorter), bevore it gets slack. This allows to distribute the
> result of a local deformation of the rim over more spokes.
no, you're believing jobst's badly mistaken theory. spokes slacken
because of rim distortion, not load capacity of the spokes. if the rim
was infinitely stiff, the bottom spokes would unload no more than the
top spokes would load. thus the stiffer the rim, the less the required
spoke elasticity. modern [deeper] rims are stiffer than old shallow
rims, thus you don't need skinny elastic spokes like you did before.
>
> Andreas - riding a touring tandem with more than 220kg total weight
> without spoke problems
yes, because of the spoke material - modern vacuum de-gassed stainless
steels and doubtless, stiffer rims!
jim beam
rubbish. spoke tension is a function of rim strength. given that spoke
tension on the drive side is therefore finite, in modern steeply dished
wheels, spoke slackening is inevitable. thus thread lock is essential.
and unsurprisingly, wheel manufacturers, you know, people that bother
to test these things, all universally use some kind of thread locking
mechanism.
the fact that this is simple mechanics and not a function of build
automation doesn't bother you though apparently.
>
> I discovered this many years ago while watching a Holland Mechanics
> machine, the first one Wheelsmith acquired. It was then that Rick
> Hjertberg came up with Spoke Prep to cover for loosely spoked wheels.
>
> I've talked at length with Holland Mechanics and BMD, makers of wheel
> building machines, about a simple modification that would enable their
> machines to build at any desired higher tension than is presently
> possible.
jobst, when will you learn that you cannot arbitrarily increase spoke
tension without cracking rims? unless you want rims that are
unacceptably heavy, you have to moderate spoke tension. thankfully,
manufacturers know more than you and you continue to be ignored.
>
>> Should I consider re-doing the wheel one nipple (with lube) at a
>> time, or am I probably OK? The bike is used for daily urban
>> commuting, and about a week of loaded touring every summer.
>
> Just add a drop of oil at the spoke nipple/eyelet and spoke/nipple
> interfaces. It will wick in to where it is needed and you will find
> spoke wrench torque4 greatly reduced. Get the book. It goes into
> adequate detail on these issues.
yeah. it goes into flights of fantasy about spoke fatigue, rim
anodizing, neglects to do the math on rear wheel spoke tension ratios
and dismisses the effects of spoke stiffness in tensiometer math too.
jim beam
> Ken Freeman wrote:
>
>> Excellent comments, Carl! I would think the angles are accurate
>> enough that the surprising difference is real. They are small, but
>> they can be calculated accurately from hub and flange dimensions,
>> and there's really no difficulty in measuring hub and flange
>> dimensions accurately, with a vernier, dial, or digital caliper.
>
>> If the angles are good, the only explanation is that in newer hubs
>> the non-drive side flange has been moved inboard to compensate the
>> disparity. or am I missing something?
>
> ... Not to overlook the offset for gear clusters, the feature that
> made rear hubs so laterally weak with have lopsided spoke tension.
> Manufacturers just moved the flanges closer together to reduce the
> angle.
under your misguided bleatings that increasing tension increases
strength no doubt.
> They had to, with so few spokes that require higher tension
> than formerly, so the right side with it's few spokes, carries nearly
> all the load, the left side spokes easily becoming slack in use...
> SpokePrep to the rescue!
it's a shame you don't understand the appropriate use of sarcasm jobst.
especially when this whole thread is the result of your woeful
misconception.
jim beam
> I'm a little confused on the tension ratio of a dished rear wheel.
> Jobst Brandt's book indicates that the ratio for an eight speed hub is
> about 2.5:1.
>
> As an example, I am using Spocalc. Velocity Deep V 700C rear rim with
> a Dura Ace 10sp hub, and its telling the the left bracing angle is
>
> Doing a simple vector analysis and using a value of 100 for the left
> side tension, I'm coming up with 141 as the right side tension. I'm
> 141.15 sin 4.6� = 11.32(right side lateral component)
>
> The values of 100 and 141 are the tension values of the spokes, so it
> seems to me that the actual ratio is 141/100 = 1.41:1
>
> Where does Jobst's ratio of 2.5:1 come from? What am I missing here?
>
> Greg
what you're missing, and what jobst neglects to tell you in his book,
is that the ratio of spoke tensions is the ratio of the sines of the
radial spoke angles as they intersect with the rim. this is derived
from lami's theorem, the essential explanation of force vector
equilibrium. for small angles, the ratio roughly equals the ratio of
the angles, so you don't even need to press the "sin" button.
as for the disparity between the old days and your modern wheel, as has
already been revealed, modern flange spacing is different.
jim beam
> Greg who? wrote:
>
>> I'm a little confused on the tension ratio of a dished rear wheel.
>> Jobst Brandt's book indicates that the ratio for an eight speed hub
>> is about 2.5:1.
>
>> As an example, I am using Spocalc. Velocity Deep V 700C rear rim
>> angle is 6.5º and the right bracing angle is 4.6º.
>
>> Doing a simple vector analysis and using a value of 100 for the left
>> side tension, I'm coming up with 141 as the right side tension. I'm
>> component) 141.15 sin 4.6º = 11.32(right side lateral component)
>
>> The values of 100 and 141 are the tension values of the spokes, so
>> it seems to me that the actual ratio is 141/100 = 1.41:1
>
tan??? the tension ratio is the ratio of sines - lami's theorem. tan
is the ratio of spoke lengths. either way, you don't explain why.
>
>> Where does Jobst's ratio of 2.5:1 come from? What am I missing
>> here?
>
> What flange spacing are you using and what is the offset? The values
> in the book were derived from Campagnolo RECORD hubs of the day.
> These were initially designed for 4-speed gear clusters. Like the
> ones you see in the graphic figures and on the cover. This was not
> intended to be a definitive value but rather an example of how
> strongly more and more sprockets affect wheel reliability.
how does increasing tension increase strength in a material that's
equally strong in both tension and compression jobst?
Tom Ace
> tan??? the tension ratio is the ratio of sines - lami's theorem. tan
> is the ratio of spoke lengths.
cos for the spoke lengths,
tan for the flange-to-center distances.
Tom Ace
jim beam
there you go. jobst has tan of the spoke angles.
Ben C
> jobst....@stanfordalumni.org wrote:
>> Ken Freeman wrote:
>>
>>> Excellent comments, Carl! I would think the angles are accurate
>>> enough that the surprising difference is real. They are small, but
>>> they can be calculated accurately from hub and flange dimensions,
>>> and there's really no difficulty in measuring hub and flange
>>> dimensions accurately, with a vernier, dial, or digital caliper.
>>
>>> If the angles are good, the only explanation is that in newer hubs
>>> the non-drive side flange has been moved inboard to compensate the
>>> disparity. or am I missing something?
>>
>> ... Not to overlook the offset for gear clusters, the feature that
>> made rear hubs so laterally weak with have lopsided spoke tension.
>> Manufacturers just moved the flanges closer together to reduce the
>> angle.
>
> under your misguided bleatings that increasing tension increases
> strength no doubt.
I think you really do need the flanges closer together for a rear wheel
or the left/right tension differential is too great and the spokes will
be too loose on the left (even with threadlock).
I'm sure they wouldn't do it otherwise-- you want the best bracing angle
you can get.
It is slightly absurd that we have 130mm rear dropouts and rear hub
flanges only 50mm apart, but that's the effect of so much dish.
P. Chisholm
I have never used threadlock on any wheel I have built, BTW. About
5000-6000 or so and counting.
P. Chisholm
Seeing some here proclaim what is 'essential' or not when building a
bicycle wheel makes me wonder if they ever have actually built a
bicycle wheel.
jim beam
> On 2009-04-25, jim beam <retard...@bad.example.net> wrote:
>> jobst....@stanfordalumni.org wrote:
>>> Ken Freeman wrote:
>>>
>>>> Excellent comments, Carl! I would think the angles are accurate
>>>> enough that the surprising difference is real. They are small, but
>>>> they can be calculated accurately from hub and flange dimensions,
>>>> and there's really no difficulty in measuring hub and flange
>>>> dimensions accurately, with a vernier, dial, or digital caliper.
>>>> If the angles are good, the only explanation is that in newer hubs
>>>> the non-drive side flange has been moved inboard to compensate the
>>>> disparity. or am I missing something?
>>> ... Not to overlook the offset for gear clusters, the feature that
>>> made rear hubs so laterally weak with have lopsided spoke tension.
>>> Manufacturers just moved the flanges closer together to reduce the
>>> angle.
>> under your misguided bleatings that increasing tension increases
>> strength no doubt.
>
> I think you really do need the flanges closer together for a rear wheel
> or the left/right tension differential is too great and the spokes will
> be too loose on the left (even with threadlock).
i don't. i had the misfortune of briefly owning/riding a ritchie wheel
with jobst-inspired close hub flanges. it was by far the worst shimmy
nightmare wheel i've ever had. all because of low lateral stability
caused by low bracing angles.
>
> I'm sure they wouldn't do it otherwise-- you want the best bracing angle
> you can get.
indeed you do. and for a dished wheel, that does /not/ mean having both
flanges close together just for tension. you're better off having a
better bracing angle on at least one side than you are having lousy ones
on both - a wheel doesn't collapse just because a few spokes may go
loose occasionally.
>
> It is slightly absurd that we have 130mm rear dropouts and rear hub
> flanges only 50mm apart, but that's the effect of so much dish.
use a stiffer rim and use unbutted spokes on the drive side. and/or use
only half the spoke count on the non-drive side. that's what campy do
for their "g3" rears. it's proven very reliable in the field.
jim beam
don't you crack rims? ma3's? i've not cracked any yet. if you used
lower [manufacturer spec] spoke tension and linseed, maybe you'd not
have that problem.
jobst....@stanfordalumni.org
http://www.avocet.com/wheelbook/wheelbook.html
> I have never used thread lock on any wheel I have built, BTW. About
> 5000-6000 or so and counting.
Nor have I, but what does that have to do with lubricating spokes and
spoke nipples for wheel building, to which this appears to be a
response?
Jobst Brandt
jim beam
who are you to question? how does "the bicycle wheel" address spoke
tension ratio? you don't touch on the math at all and it's the #1 asked
spoke tension question on this group. "(tan(6.5)/tan(4.6)) = 1.416"
doesn't explain a damned thing.
rruff
> because of rim distortion, not load capacity of the spokes. if the rim
> was infinitely stiff, the bottom spokes would unload no more than the
> top spokes would load. thus the stiffer the rim, the less the required
> spoke elasticity. modern [deeper] rims are stiffer than old shallow
> rims, thus you don't need skinny elastic spokes like you did before.
Though radially stiff rims spread things out a little, it isn't as
much as you might think. Even with a 30mm tall aluminum rim and 18
spokes, the great majority of the load is "carried" by the bottom 2 or
3 spokes in normal use.
rruff
> On 2009-04-25, jim beam <retard-fin...@bad.example.net> wrote:
I think modern road bikes could benefit from 135mm flange spacing like
MTBs. The way things are, the DS can only have ~19mm of offset...
max... less for Campy. Since the lateral stiffness imparted by the
spokes goes up approximately with the *square* of the bracing angle,
you certainly don't want narrow flanges. You also don't want NDS
tension being so low that spokes go slack. The "sweet spot" for NDS
spacing is around 2x the DS spacing.
jim beam
but, in terms of understanding the fundamental concepts, as opposed to
trying to jump in head first and mistakenly banging your head in the
shallow end because you didn't bother to check, if you understand what
happens with spoke loading on an infinitely stiff rim, /then/ you can
move to the next level and bring in rim distortion. that's what you do
when considering wing loading. that's what you do when considering gear
loading.
yes indeed, the lower spokes /do/ unload the most, but the /reason/ is
rim distortion. end of story. all this extrapolation and presumption
about "standing" is fundamentally missing half the story. to
extrapolate from a position of this ignorance and presume to lecture
therefrom, is just unbelievably stupid.
Nick L Plate
Dont be silly, how do you expect thinner spokes to build a stronger
wheel if the hub isn't held up by the loss of lower spoke tension?
JB's shrink told him he had to destress. He sees that the loss in
tension of each spoke satisfying the "destress" mantra, and continues
it with "stress-relief" of spokes, some magical incantation and waving
of hands removes the evil stress from the despicable spooks. Others
may also desire this temporary relief. A excalation in stress is sure
to return with buckled and fractured rims. Best not to spoil the
associates immediate gratification of following (lemmings) the
altightly JB
Ben C
> On Apr 25, 2:54 am, Ben C <spams...@spam.eggs> wrote:
>> It is slightly absurd that we have 130mm rear dropouts and rear hub
>> flanges only 50mm apart, but that's the effect of so much dish.
>
> I think modern road bikes could benefit from 135mm flange spacing like
> MTBs. The way things are, the DS can only have ~19mm of offset...
> max... less for Campy. Since the lateral stiffness imparted by the
> spokes goes up approximately with the *square* of the bracing angle,
> you certainly don't want narrow flanges. You also don't want NDS
> tension being so low that spokes go slack. The "sweet spot" for NDS
> spacing is around 2x the DS spacing.
Yes, although I wonder if then banging your heels on the chainstays
would be a problem given that road bikes tend to have the back wheel as
far forward as possible.
Only 2.5mm more each side, so I guess it probably wouldn't make much
difference.
jim beam
2.5mm is a honking great percentage on bracing angle and an even bigger
one on spoke load delta since it's a function of 1/sin that angle.
jim beam
altightly jobst brandt??? actually, that's strangely appropriate!
jobst....@stanfordalumni.org
>>> It is slightly absurd that we have 130mm rear dropouts and rear
>>> hub flanges only 50mm apart, but that's the effect of so much
>>> dish.
>> I think modern road bikes could benefit from 135mm flange spacing
>> like MTBs. The way things are, the DS can only have ~19mm of
>> offset... max... less for Campy. Since the lateral stiffness
>> imparted by the spokes goes up approximately with the *square* of
>> the bracing angle, you certainly don't want narrow flanges. You
>> also don't want NDS tension being so low that spokes go slack. The
>> "sweet spot" for NDS spacing is around 2x the DS spacing.
> Yes, although I wonder if then banging your heels on the chainstays
> would be a problem given that road bikes tend to have the back wheel
> as far forward as possible.
So why do road bikes have the back wheel as far forward as possible?
Many years ago, having had problems with untensioned wheelies while
climbing seated, I decided to no longer follow that convention and had
my frames made with rear dropouts three inches farther back than
currently popular. That made space for mounting my Silca pump behind
the seat tube where it wasn't in the way when carrying the bicycle
over the shoulder.
What is it riders believe having the rear wheel in the seat tube
accomplishes? Is this like driving a black pickup with the body a few
feet above the axles. Ya gotta have it and with loud rumbling exhaust
pipes.
> Only 2.5mm more each side, so I guess it probably wouldn't make much
> difference.
Unless you have larger than size 48 shoes, artistically curved
chainstays ought to make enough clearance. That way the frame can be
so narrow that taking out the rear wheel requires letting the air out
of the tire, while the dropouts are out in the breeze.
Hey, but it's all CF and the S-shaped seat- and chainstays soften the
ride.
Jobst Brandt
Ben C
No, I meant much difference to whether you banged your feet on the
chainstays or not.
jim beam
er, you're an "engineer", right? why don't you calculate the difference
in a 10% difference in length makes to tube elasticity?
>
>> Only 2.5mm more each side, so I guess it probably wouldn't make much
>> difference.
>
> Unless you have larger than size 48 shoes, artistically curved
> chainstays ought to make enough clearance. That way the frame can be
> so narrow that taking out the rear wheel requires letting the air out
> of the tire, while the dropouts are out in the breeze.
yeah, and in tension or compression, what difference does a curved tube
make vs a bent one??? you know euler bending, right?
>
> Hey, but it's all CF and the S-shaped seat- and chainstays soften the
> ride.
but apparently they're unable to penetrate the luddite brain.
rruff
> Only 2.5mm more each side, so I guess it probably wouldn't make much
> difference.
That is actually a pretty big improvement when you are starting with
only ~18mm of DS spacing. It is a 14% increase in bracing angle, and
if you then space the NDS over an equivalent percentage, the lateral
stiffness should be at least 20% higher.
Nick L Plate
> What is it riders believe having the rear wheel in the seat tube
> accomplishes? Is this like driving a black pickup with the body a few
> feet above the axles. Ya gotta have it and with loud rumbling exhaust
> pipes.
The tight racing frame was a Harry Quinn trademark.
Harry Quinn built frames like this. Norman Sheil won on Harry
Quinn's. Terry Dolan copied Quinn, I think Terry worked for him when
he was racing. When HQ left Liverpool, TD was there to pick up the
work that Soens & Walvale couldn't fulfill. Terry's frames have a low
failure rate. The Dolan frames are used by the national squad.
Everyone now copies Dolan. If TD had been crap at brazing, then I
think the supertight frame would have not existed. I have a Dolan
road frame, to his pattern. It was tight at the time, but bears
nothing in comparison to some of the copies I've seen. I can fit a
28mm tyre with a skinny mudguard. The bike was not specced for
'guards as I had a good second frame for winter use. When it came to
it, the race frame was that good, I used it all the time, mostly
without guards through the winter. The demon descender, on his Dolan
strikes again. (actually called a Cougar)(or mountain cat)
jobst....@stanfordalumni.org
>> What is it riders believe having the rear wheel in the seat tube
>> accomplishes? Is this like driving a black pickup with the body a
>> few feet above the axles. Ya gotta have it and with loud rumbling
>> exhaust pipes.
> The tight racing frame was a Harry Quinn trademark.
But what do riders believe this shortening the smallest diameter frame
tubes by about an inch does for their riding, many of them never
entering a sanctioned race?
Jobst Brandt
Johnny Twelve-Point presented by JFT
What do riders belie that lengthening the tubes will do for their
riding?
Nick L Plate
> But what do riders believe this shortening the smallest diameter frame
> tubes by about an inch does for their riding, many of them never
> entering a sanctioned race?
Originally the wannabe's copied the winners, which meant a Harry
Quinn. Some of these thousands of HQ owners did of course become
winners so promoting the style of which Quinn was (is?) known. Quinn
was only one of many great framebuilders in Liverpool. He was the
last of his generation to framebuild in the area because of the
fanatical following he had. I'd have liked to have been able to slip
my hand between tyre and seatube but I left the builder (Terry Dolan)
to select what he though most appropriate for the likely races I'd be
entering. He was/had been an accomplished rider, as well as being
mentored by HQ. I knew I needed something a little smaller than
previously, his eye met with my assesment so I put my trust in him
after coming to a mutually agreeable price for a complete bike. The
detail of tyre to seat tube distance was not important enough to me.
I knew he built em close, I accepted his usual suggestion. Which
means today, I'd get more for it than an atypical Dolan frame.
I dont understand why someone with no intention of racing would give
any thought to the length of chainstays. I think it may have gained
popularity because there was (is?) a belief that long chainstays
"sapped your strength" when climbing hills, rather than a low (power
deliverance)/weight ratio. The only realadvantage is when a team can
group together and work, drafting between 3/4" and rubbing of tyres,
and overlapping wheels(only with trusted teammates) (which negates the
advantage of short stays)
Nick L Plate
Not a Semitic reference.
Johnny Twelve-Point presented by JFT
<tj-...@blueyonder.co.uk> wrote:
>I dont understand why someone with no intention of racing would give
>any thought to the length of chainstays.
Does that work both ways? Is someone not racing allowed to think
about longer stays, but not shorter?
AMuzi
>> I dont understand why someone with no intention of racing would give
>> any thought to the length of chainstays.
Johnny Twelve-Point presented by JFT wrote:
> Does that work both ways? Is someone not racing allowed to think
> about longer stays, but not shorter?
Is it still Ludwig Wittgenstein Week on r.b.t.?
'I think my chainstays are short but they are long'
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
jim beam
thank you.
jim beam
i'm still waiting for him to show his numbers on elasticity of longer tube.
Nick L Plate
> >Nick L Plate <tj-j...@blueyonder.co.uk> wrote:
> >> I dont understand why someone with no intention of racing would give
> >> any thought to the length of chainstays.
>
> Johnny Twelve-Point presented by JFT wrote:
>
> > Does that work both ways? Is someone not racing allowed to think
> > about longer stays, but not shorter?
>
> Is it still Ludwig Wittgenstein Week on r.b.t.?
>
> 'I think my chainstays are short but they are long'
Questions over virility? Relating to the length of ones chainstays?
Quite possibly. Come to think of it, those who consitently had shaven
legs (and oil) were more concerned over the length of their chainstays
than the more athletic(really), couldn't give a **** guys.
Sergio Moretti
<usenetrem...@jt10000.com> wrote:
About 25 years ago, longer chainstays were recommended for a smoother
ride & touring bikes.
Transferring weight to the front wheel has other advantages too. For
example, my bike has short (41cm) stays & climbing while seated
results in an excessively light front end!
I'll be specifying longer chainstays for my next frame.
Sergio Moretti
Nick L Plate
When your riding in the wet, you need the weight on the rear to
maintain traction on a slippy steep climb.
Ben C
> Ben C? wrote:
>
>>>> It is slightly absurd that we have 130mm rear dropouts and rear
>>>> hub flanges only 50mm apart, but that's the effect of so much
>>>> dish.
>
>>> I think modern road bikes could benefit from 135mm flange spacing
>>> like MTBs. The way things are, the DS can only have ~19mm of
>>> offset... max... less for Campy. Since the lateral stiffness
>>> imparted by the spokes goes up approximately with the *square* of
>>> the bracing angle, you certainly don't want narrow flanges. You
>>> also don't want NDS tension being so low that spokes go slack. The
>>> "sweet spot" for NDS spacing is around 2x the DS spacing.
>
>> Yes, although I wonder if then banging your heels on the chainstays
>> would be a problem given that road bikes tend to have the back wheel
>> as far forward as possible.
>
> So why do road bikes have the back wheel as far forward as possible?
We've discussed this here many times before. Possible reasons, in no
particular order of bogosity, are:
1. Weighs less
2. Stiffer
3. Fashion
4. More "sporty handling"
5. Lets following rider get closer in a paceline
6. Prevents you from fitting fenders
[...]
>> Only 2.5mm more each side, so I guess it probably wouldn't make much
>> difference.
>
> Unless you have larger than size 48 shoes, artistically curved
> chainstays ought to make enough clearance.
Maybe, but I think you'd need a rather tight curve right at the end.
Of course the other fix would be a wider BB, but many riders prefer a
narrower one ("low Q" that's called).
Ben C
Agreed, I meant: not much difference to whether you kick your chainstays
while pedalling.
But actually it might make some difference to that as there is very
little room there even with 130mm spacing.
jobst....@stanfordalumni.org
>>>>> It is slightly absurd that we have 130mm rear dropouts and rear
>>>>> hub flanges only 50mm apart, but that's the effect of so much
>>>>> dish.
>>>> I think modern road bikes could benefit from 135mm flange spacing
>>>> like MTB's. The way things are, the DS can only have ~19mm of
>>>> offset... max... less for Campy. Since the lateral stiffness
>>>> imparted by the spokes goes up approximately with the *square* of
>>>> the bracing angle, you certainly don't want narrow flanges. You
>>>> also don't want NDS tension being so low that spokes go slack. The
>>>> "sweet spot" for NDS spacing is around 2x the DS spacing.
>>> Yes, although I wonder if then banging your heels on the chainstays
>>> would be a problem given that road bikes tend to have the back wheel
>>> as far forward as possible.
>> So why do road bikes have the back wheel as far forward as possible?
> We've discussed this here many times before. Possible reasons, in no
> particular order of bogosity, are:
> 1. Weighs less
> 2. Stiffer
> 3. Fashion
> 4. More "sporty handling"
> 5. Lets following rider get closer in a paceline
> 6. Prevents you from fitting fenders
These are all empty claims and as I mentioned, they are like the
excuses riders often gave for shaving and "embrocating" legs. Just
excuses for a fashion trend. Just like the guys with the jacked up
SUV's and pickups. They need them and locally turn donuts in muddy
pull-outs along highways to make them muddy and look well used.
> [...]
>>> Only 2.5mm more each side, so I guess it probably wouldn't make
>>> much difference.
>> Unless you have larger than size 48 shoes, artistically curved
>> chainstays ought to make enough clearance.
> Maybe, but I think you'd need a rather tight curve right at the end.
> Of course the other fix would be a wider BB, but many riders prefer
> a narrower one ("low Q" that's called).
Like all the rest of the syndrome.
Jobst Brandt
Johnny Twelve-Point presented by JFT
>These are all empty claims and as I mentioned, they are like the
>excuses riders often gave for shaving and "embrocating" legs. Just
>excuses for a fashion trend. Just like the guys with the jacked up
>SUV's and pickups. They need them and locally turn donuts in muddy
>pull-outs along highways to make them muddy and look well used.
Why so much need to rag on other people? It's one thing to respond to
racer siliness when someone brings it up, but you seem to *enjoy*
bringing it up and denouncing it.
I don't undestand why you get pleasure in this, or what the purpose of
your criticism in this venue is.
RonSonic
I'll differ with you to the point of saying that all of those things are true,
just not important. Short chainstays are indeed fashionable and do promote a
racy "diving into the corner" feeling and &tc.. None of those are worth a damp
fart but they are so.
Tom Sherman
Ragging on users of over-sized personal use trucks is fine, since they
endanger other road users more than normal passenger cars.
--
Tom Sherman - 42.435731,-83.985007
LOCAL CACTUS EATS CYCLIST - datakoll
Michael Press
RonSonic <rons...@tampabay.rr.com> wrote:
I enjoy a bike that dives into a corner, and have one;
though not to the degree of a 410 mm chain stay.
--
Michael Press
Johnny Twelve-Point presented by JFT
Any thoughts about shaving and embrocation?
Tom Sherman
Clive George
news:gt5p9t$snp$1...@news.eternal-september.org...
>> Any thoughts about shaving and embrocation?
>>
> Harmless to others.
I have a pack of razor blades in the house, and the primary use is
bike-related - does that count?
(used for removing flashing from inner tubes prior to patching)
Johnny Twelve-Point presented by JFT
<sunsetss000...@yahoo.com> wrote:
>Johnny Twelve-Point presented by JFT aka John Forrest Tomlinson wrote:
>> On Mon, 27 Apr 2009 18:05:48 -0500, Tom Sherman
>> <sunsetss000...@yahoo.com> wrote:
>>
>>> Johnny Twelve-Point presented by JFT aka John Forrest Tomlinson wrote:
>>>> On 27 Apr 2009 14:03:59 GMT, jobst....@stanfordalumni.org wrote:
>>>>
>>>>> These are all empty claims and as I mentioned, they are like the
>>>>> excuses riders often gave for shaving and "embrocating" legs. Just
>>>>> excuses for a fashion trend. Just like the guys with the jacked up
>>>>> SUV's and pickups. They need them and locally turn donuts in muddy
>>>>> pull-outs along highways to make them muddy and look well used.
>>>> Why so much need to rag on other people? It's one thing to respond to
>>>> racer siliness when someone brings it up, but you seem to *enjoy*
>>>> bringing it up and denouncing it.
>>>>
>>>> I don't undestand why you get pleasure in this, or what the purpose of
>>>> your criticism in this venue is.
>>> Ragging on users of over-sized personal use trucks is fine, since they
>>> endanger other road users more than normal passenger cars.
>>
>> Any thoughts about shaving and embrocation?
>>
>Harmless to others.
Right -- so Brand't comments were even worse regarding cyclists
different than him- equating something harmless to other people with
stuff that isn't, just because he apparently doesn't like it.
LAME.
Sandy
news:rubrum-41A9A4....@news.sf.sbcglobal.net...
For your next bike, get one that also gets you out of the corner.
If it's banked high, not to worry.
--
Bonne route !
Sandy
Verneuil-sur-Seine FR
jobst....@stanfordalumni.org
>> These are all empty claims and as I mentioned, they are like the
>> excuses riders often gave for shaving and "embrocating" legs. Just
>> excuses for a fashion trend. Just like the guys with the jacked up
>> SUV's and pickups. They need them and locally turn donuts in muddy
>> pull-outs along highways to make them muddy and look well used.
> Why so much need to rag on other people? It's one thing to respond
> to racer siliness when someone brings it up, but you seem to *enjoy*
> bringing it up and denouncing it.
Oh! I see you take this personally, fitting the description.
> I don't undestand why you get pleasure in this, or what the purpose of
> your criticism in this venue is.
It' less pleasure than a duty to squelch these tales for the benefit
of less technically questioning readers, who in part rely on these
stories that go unchallenged to be fact. I think it is a proper
response to years of hearing the same myth and lore repeated to become
religious dogma that riders new and old repeat to others. Among those
tales are all the BS stories I heard more than 50 years ago and still
hear told as fact. Long ago, Bicycling Magazine seemed to lay these
to rest, but it takes stronger weed killer to stop their proliferation
and perpetual life.
So why do you shoot from cover of anonymity? I suppose you don't want
to be quoted on what you offer the readers. You might have noticed
that the rudest contributors in this newsgroup are untraceable aliases.
Using you own words, I ask:
# I don't undestand why you get pleasure in this, or what the purpose of
# your criticism in this venue is.
Jobst Brandt
Tom Sherman
> Johnny anonymous snipes:
>
Hardly anonymous or unknown to "wreck bike":
<http://www.wiredtowinthemovie.com/profile_johntomlinson.html>.
jobst....@stanfordalumni.org
I note that you say: "diving into the corner" feeling and &tc.
Placebos often make subjects "feel" claimed results, but we needn't
blow the horn for such believed improvements for millisecond imagined
or derived advances or sit on our hands as they become part of
bicycling fact.
Jobst Brandt
jim beam
> Johnny anonymous snipes:
>
>>> These are all empty claims and as I mentioned, they are like the
>>> excuses riders often gave for shaving and "embrocating" legs. Just
>>> excuses for a fashion trend. Just like the guys with the jacked up
>>> SUV's and pickups. They need them and locally turn donuts in muddy
>>> pull-outs along highways to make them muddy and look well used.
>
>> Why so much need to rag on other people? It's one thing to respond
>> to racer siliness when someone brings it up, but you seem to *enjoy*
>> bringing it up and denouncing it.
>
> Oh! I see you take this personally, fitting the description.
>
>> I don't undestand why you get pleasure in this, or what the purpose of
>> your criticism in this venue is.
>
> It' less pleasure than a duty to squelch these tales for the benefit
> of less technically questioning readers, who in part rely on these
> stories that go unchallenged to be fact. I think it is a proper
> response to years of hearing the same myth and lore repeated to become
> religious dogma
eh? like "stress relief" you mean? like "anodizing cracks rims" you
mean"? like spoke tension "as high as the rim can bear" you mean?
/that/ kind of myth and lore repeated to become religious dogma?
> that riders new and old repeat to others. Among those
> tales are all the BS stories I heard more than 50 years ago and still
> hear told as fact. Long ago, Bicycling Magazine seemed to lay these
> to rest, but it takes stronger weed killer to stop their proliferation
> and perpetual life.
>
> So why do you shoot from cover of anonymity? I suppose you don't want
> to be quoted on what you offer the readers. You might have noticed
> that the rudest contributors in this newsgroup are untraceable aliases.
> Using you own words, I ask:
>
> # I don't undestand why you get pleasure in this, or what the purpose of
> # your criticism in this venue is.
>
you're such a bullshitter jobst. if you didn't hide behind your
"stanford alumni" shield, which frankly i have absolutely /no/ idea how
you achieved given your evident lack of ability, or retained, given your
constant shaming of them with your constant mistakes, people would stand
in line to laugh in your face. "anonymous" is the only way to not let
you play your fucked-up retarded games and pissing matches your way.
you bring it on yourself so you have /no/ right to complain.
jim beam
and for the great and mighty jobst brandt's next trick, "how bent tube
is just as stiff as straight tube", and "how spoke elbows do not bend on
loading". after the intermission, he'll present "short tube is just as
elastic as long tube" and "wheelbase does not affect steering". any
generous contributions you may care to make will be donated to the
"stanford alumni who died from the shame of association" society
jobst....@stanfordalumni.org
http://www.sheldonbrown.com/brandt/
17-3/8" or 441.3mm chainstays. I haven't met any faster bicyclists
descending here or in the Alps where there are many tight turns that
require short wheelbase tourist buses that make these turns at fork
lift speeds.
http://tinyurl.com/9ah2r
http://tinyurl.com/agnvh
I chose this pass because the Stelvio IS the greatest of the great
mountain passes in the Alps. There are many passes, but none as
startling as the Stelvio in all its glory. Ive ridden it in sun,
rain, and snow and it never ceases to leave me speechless. As Cino
Cinelli said when asked about the greatest pass: "There is only
one... (long pause), the Stelvio!" as he recalled his riding career
looking off into the distance.
I can't say it any better.
After a heavy winter the pass, an attempt by the resident dozer to
clear it, but alas it is snowing more onto the 3+ meter snow pack:
http://webcam.popso.it/stelvio.php?PASSOALTO2
On the west coast, we are 9 hours later so try it during daylight in
central European time.
Last summer was a great ride over the Stelvio as I reported in the
University of Trento (I) Bike Pages [50 years Stelvio]:
http://www.trentobike.org/byauthor/JobstBrandt.html
Jobst Brandt
jim beam
you know, it's strange, but some of us fail to connect the dots between
you having ridden the alps, and you knowing what the fuck you're talking
about on geometry. can you explain? or were we somehow supposed to be
impressed and therefore bamboozled? 'cos i'm not.
jobst....@stanfordalumni.org
>>>> These are all empty claims and as I mentioned, they are like the
>>>> excuses riders often gave for shaving and "embrocating" legs.
>>>> Just excuses for a fashion trend. Just like the guys with the
>>>> jacked up SUV's and pickups. They need them and locally turn
>>>> donuts in muddy pull-outs along highways to make them muddy and
>>>> look well used.
>>> Why so much need to rag on other people? It's one thing to
>>> respond to racer siliness when someone brings it up, but you seem
>>> to *enjoy* bringing it up and denouncing it.
>>> I don't undestand why you get pleasure in this, or what the
>>> purpose of your criticism in this venue is.
>> Ragging on users of over-sized personal use trucks is fine, since
>> they endanger other road users more than normal passenger cars.
> Any thoughts about shaving and embrocation?
If you have to lie about its purpose, there is something amiss.
Bikies legs are shaved and oiled up for the same reason body builders
do it to their exposed body. It makes muscle definition stand out,
and bikies have only legs to show unlike weight lifters and body
builders. Just look at pictures of the former Terminator, our dear
governor "Arnoldt", as he says it in his Austrian twang.
Jobst Brandt
Johnny Twelve-Point presented by JFT
How come you haven't answered my question: why do you feel the need to
go out of the way to diss people who aren't doing anything to hurt
you?
Really, why the disses? Do you feel you are educating people? Does it
somehow bother you?
Please explain.
Johnny Twelve-Point presented by JFT
>Johnny who? snipes:
For someone who feels the need to include the famous university in the
subject line of his usenet posts, you really shouldn't start on this
"who?" crap.
Nate Nagel
The trucks don't endanger road users, if there's any endangering going
on it's the driver.
Yes, I have a pickup truck, but most of the time when I'm driving it
it's either a) because I'm hauling something or on my way to haul
something or b) it's been so long since I needed to haul something I
want to keep the seals wet and the tires from flat-spotting.
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
Tom Sherman
Tom Sherman
> Tom Sherman wrote:
>> Johnny Twelve-Point presented by JFT aka John Forrest Tomlinson wrote:
>>> On 27 Apr 2009 14:03:59 GMT, jobst....@stanfordalumni.org wrote:
>>>
>>>> These are all empty claims and as I mentioned, they are like the
>>>> excuses riders often gave for shaving and "embrocating" legs. Just
>>>> excuses for a fashion trend. Just like the guys with the jacked up
>>>> SUV's and pickups. They need them and locally turn donuts in muddy
>>>> pull-outs along highways to make them muddy and look well used.
>>>
>>> Why so much need to rag on other people? It's one thing to respond to
>>> racer siliness when someone brings it up, but you seem to *enjoy*
>>> bringing it up and denouncing it.
>>>
>>> I don't undestand why you get pleasure in this, or what the purpose of
>>> your criticism in this venue is.
>>
>> Ragging on users of over-sized personal use trucks is fine, since they
>> endanger other road users more than normal passenger cars.
>>
>
> The trucks don't endanger road users, if there's any endangering going
> on it's the driver.
>
to kill a cyclist or pedestrian in a low speed collision than a Honda
Civic or Toyota Corolla? Or the larger truck is not more likely to kill
another motorist in a higher speed collision? All carry one person
equally well.
We won't mention that the larger vehicle blocks the view of others and
has poorer collision avoidance.
> Yes, I have a pickup truck, but most of the time when I'm driving it
> it's either a) because I'm hauling something or on my way to haul
> something or b) it's been so long since I needed to haul something I
> want to keep the seals wet and the tires from flat-spotting.
>
I have driven a lot in pick-ups in recent years, but they have been
company fleet vehicles, and I was either carrying bulky test equipment
or going semi-off-road on construction sites.
Johnny Twelve-Point presented by JFT
<sunsetss000...@yahoo.com> wrote:
>Johnny Twelve-Point presented by JFT aka John Forrest Tomlinson wrote:
>> On 28 Apr 2009 04:28:10 GMT, jobst....@stanfordalumni.org wrote:
>>
>>> Johnny who? snipes:
>>
>> For someone who feels the need to include the famous university in the
>> subject line of his usenet posts, you really shouldn't start on this
>> "who?" crap.
>>
>Where are Harvard and Yale?
I don't see how that's relevant to this discussion - as far as I can
tell there is only one regular poster in this group who advertises
where he went to school.
Stephen Bauman
>
> Hey, but it's all CF and the S-shaped seat- and chainstays soften the
> ride.
>
If that's a reference to the Hetchins curly stays, then ride quality had
nothing to do with the reason for the design. In fact the stays were
thicker than normal round-oval-round tubing used for the chain stay.
Kerry Montgomery
"Johnny Twelve-Point presented by JFT" <usenet...@jt10000.com> wrote in
message news:fjkdv4pi8cg8k5jlv...@4ax.com...
A search of Google Groups for messages authored by @stanfordalumni.org
returns messages by many different authors, so this may be the default name
used by the stanfordalumni.org newsgroup reader.
Kerry
jobst....@stanfordalumni.org
>> Hey, but it's all CF and the S-shaped seat- and chainstays soften
>> the ride.
> If that's a reference to the Hetchins curly stays, then ride quality
> had nothing to do with the reason for the design. In fact the stays
> were thicker than normal round-oval-round tubing used for the chain
> stay.
Of course. The Hetchins dodge was around having the manufacturer's
name visible on amateur racing bicycles, so the curved tubes were a
way of identifying Hetchins to the public.
However, you may have missed the threads here that claimed that one
can feel the ride comfort of various frame materials, especially CF
as well as straight and curved forks.
Jobst Brandt
AMuzi
> <sunsetss000...@yahoo.com> wrote:
>
>> Johnny Twelve-Point presented by JFT aka John Forrest Tomlinson wrote:
>>> On 28 Apr 2009 04:28:10 GMT, jobst....@stanfordalumni.org wrote:
>>>
>>>> Johnny who? snipes:
>>> For someone who feels the need to include the famous university in the
>>> subject line of his usenet posts, you really shouldn't start on this
>>> "who?" crap.
>>>
>> Where are Harvard and Yale?
Johnny Twelve-Point presented by JFT wrote:
> I don't see how that's relevant to this discussion - as far as I can
> tell there is only one regular poster in this group who advertises
> where he went to school.
"School of Hard Knocks"
does it show that much?
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
AMuzi
>> Hey, but it's all CF and the S-shaped seat- and chainstays soften the
>> ride.
Stephen Bauman wrote:
> If that's a reference to the Hetchins curly stays, then ride quality had
> nothing to do with the reason for the design. In fact the stays were
> thicker than normal round-oval-round tubing used for the chain stay.
I thought that by "CF", Jobst meant modern carbon S-stays
(lateral) not Hetchins (vertical) Reynolds stays.
jobst....@stanfordalumni.org
>>> Hey, but it's all CF and the S-shaped seat- and chainstays soften
>>> the ride.
>> If that's a reference to the Hetchins curly stays, then ride
>> quality had nothing to do with the reason for the design. In fact
>> the stays were thicker than normal round-oval-round tubing used for
>> the chain stay.
> I thought that by "CF", Jobst meant modern carbon S-stays (lateral)
> not Hetchins (vertical) Reynolds stays.
Let us not overlook that both seat- and chainstays are loaded axially
when riding over road irregularities. Regardless of magnitude,
contributors to this newsgroup have claimed the ability to feel
difference from differently shaped geometries and materials.
Jobst Brandt
Michael Press
jobst....@stanfordalumni.org wrote:
I have two bicycles. When I started riding the second I rode
it as the first. Here is a street corner coming up, going
to make a right turn, set, make the turn ... but surprise,
surprise, I was far ahead of the turn, and would have been
riding up the sidewalk (pavement) had I continued. Instead
backed off to stay in the street. Different bicycles have
different responses to control movements. Some bicycles turn
more quickly. Nothing difficult to understand here.
--
Michael Press
Nate Nagel
If you're a responsible road user, barring very rare circumstances, you
shouldn't be having any collisions.
Yes, I know, people have "Accidents" every day, but that is because most
"drivers" are piss poor drivers and most "cyclists" are piss poor
cyclists, at least insofar as following the rules of the road and taking
due care.
Don't get me wrong, I don't like being surrounded by a sea of pickups
and SUVs either, when I'm riding my bike or driving my personal car.
But there are in fact real needs for these types of vehicles, not to
mention that off-roading is fun. Simply because *most* drivers of these
vehicles are irresponsible a-holes that's no reflection on the vehicles.
Most drivers of sports cars are irresponsible a-holes. Most drivers
of econoboxes are irresponsible a-holes. Most cyclists are
irresponsible a-holes. So what?