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Any validity to these assertions?

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Jay Hill

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Jan 22, 2004, 9:03:06 PM1/22/04
to

I've heard the following two arguments from people who worked in bike
shops, and I assume they aren't valid, but I wonder enough to not
dismiss them immediately, especially the second one.

1) Do not mount a bicycle like a horse, by putting a foot in the left
pedal and swinging the right leg over the seat to the other pedal.
Allegedly this is bad because it puts too much stress on the bottom
bracket. I assume this is invalid because the wheels' spokes will flex
enough to absorb some of the stress, and besides that the bottom bracket
is strong enough that it doesn't matter.

2) Forks on fixed gear bikes with a front brake have a higher rate of
breakage because there is an too much stress from the combination of the
front wheel being driven by the fixed gear while the front brake is
applied. I assume this is invalid because the rider is either not
driving or actually braking with the fixed gear when braking with the
hand brake.


Rick Onanian

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Jan 22, 2004, 7:20:44 PM1/22/04
to
On Thu, 22 Jan 2004 18:03:06 -0800, Jay Hill <jsh...@stic.net>
wrote:

>1) Do not mount a bicycle like a horse, by putting a foot in the left
>pedal and swinging the right leg over the seat to the other pedal.

Why would you want to do this, anyway?

Either the bike goes forward from the foot on the pedal, or you use
the brake and have to trackstand while not standing still, or the
pedal is at the bottom of the stroke and is barely different from
keeping that foot on the ground.

Unless we're talking about this bike:
http://www.skibladner.no/images/penny-farthing.jpg
it should be easiest to mount with a foot on the ground.

>2) Forks on fixed gear bikes with a front brake have a higher rate of
>breakage because there is an too much stress from the combination of the
> front wheel being driven by the fixed gear while the front brake is
>applied. I assume this is invalid because the rider is either not
>driving or actually braking with the fixed gear when braking with the
>hand brake.

Sounds invalid to me. Even an inexperienced rider would not output
power into the pedals while braking; most would offer at least a
little extra braking at the rear via the pedals, whether purposely
or not.

Now, maybe on a fixed gear tandem with deaf, blind, mute riders with
no sense of balance...
--
Rick Onanian

Ted Bennett

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Jan 22, 2004, 7:34:18 PM1/22/04
to
Jay Hill <jsh...@stic.net> wrote:

> I've heard the following two arguments from people who worked in bike
> shops, and I assume they aren't valid, but I wonder enough to not
> dismiss them immediately, especially the second one.
>
> 1) Do not mount a bicycle like a horse, by putting a foot in the left
> pedal and swinging the right leg over the seat to the other pedal.
> Allegedly this is bad because it puts too much stress on the bottom
> bracket. I assume this is invalid because the wheels' spokes will flex
> enough to absorb some of the stress, and besides that the bottom bracket
> is strong enough that it doesn't matter.

I've heard this argument for some time, even from Sheldon Brown who is
quite knowledgeable about bikes. There may be something to it as
hopping on this way does put all your weight on one side of the crank,
at the same time as the bike is leaned over a little. Practically, I'm
doubtful that it's anything to worry about. Many cyclists habitually do
this (including me) and have never come to grief.



> 2) Forks on fixed gear bikes with a front brake have a higher rate of
> breakage because there is an too much stress from the combination of the
> front wheel being driven by the fixed gear while the front brake is
> applied. I assume this is invalid because the rider is either not
> driving or actually braking with the fixed gear when braking with the
> hand brake.

Pedaling while the front brake is applied is similar to braking harder,
from the perspective of the load applied to the front wheel. It's the
same situation as a freewheel bike, with this difference: true track
bikes' forks are constructed of round tubing rather than the oval shape
of many road bikes. These forks may not be as strong in the
fore-and-aft direction and were not designed for use with a front brake.
This have never been a problem for my track bike, fitted with a brake,
but YMMV.

Note that a fixed gear bike is not necessarily a track bike.

--
Ted Bennett
Portland OR

Werehatrack

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Jan 22, 2004, 7:34:34 PM1/22/04
to
On Thu, 22 Jan 2004 18:03:06 -0800, Jay Hill <jsh...@stic.net> may
have said:

>I've heard the following two arguments from people who worked in bike
>shops, and I assume they aren't valid, but I wonder enough to not
>dismiss them immediately, especially the second one.
>
>1) Do not mount a bicycle like a horse, by putting a foot in the left
>pedal and swinging the right leg over the seat to the other pedal.
>Allegedly this is bad because it puts too much stress on the bottom
>bracket. I assume this is invalid because the wheels' spokes will flex
>enough to absorb some of the stress, and besides that the bottom bracket
>is strong enough that it doesn't matter.

It may, however, break out the eye at the end of the crank where the
pedal is threaded in. I do not think the reasoning given for the
caution is sound, though my experience says that there is a different
valid issue to address here. (OTOH, the only such failures that I've
had happen to me were with one-piece cranks.)

>2) Forks on fixed gear bikes with a front brake have a higher rate of
>breakage

Well, first I'd have to see the stats on this, and then determine how
many broke because the bikes were repeatedly driven into stationary
objects. Here I must question the first principle before the rest is
even stated.

>because there is an too much stress from the combination of the
> front wheel being driven by the fixed gear while the front brake is
>applied. I assume this is invalid because the rider is either not
>driving or actually braking with the fixed gear when braking with the
>hand brake.

Utter nonsense, as far as I'm concerned. The few fixie riders I've
seen, if anything, are less likely than a conventional bike rider to
use the brake while pedalling forward. In my experience, someone
aboard a conventional bike is actually more likely to be the one doing
this, as a means of facilitating trackstanding.

How often do non-carbon, non-suspension forks break, anyway? Bloody
seldom, from what I can see.


--
My email address is antispammed; pull WEEDS if replying via e-mail.
Yes, I have a killfile. If I don't respond to something,
it's also possible that I'm busy.
Words processed in a facility that contains nuts.

Sheldon Brown

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Jan 22, 2004, 8:19:31 PM1/22/04
to
Jay Hill wrote:
>
> I've heard the following two arguments from people who worked in bike
> shops, and I assume they aren't valid, but I wonder enough to not
> dismiss them immediately, especially the second one.
>
> 1) Do not mount a bicycle like a horse, by putting a foot in the left
> pedal and swinging the right leg over the seat to the other pedal.
> Allegedly this is bad because it puts too much stress on the bottom
> bracket. I assume this is invalid because the wheels' spokes will flex
> enough to absorb some of the stress, and besides that the bottom bracket
> is strong enough that it doesn't matter.

This doesn't bother the bottom bracket, but is very stressful to the
wheels. Bicycle wheels are very strong against radial loads, but quite
weak against side loads.

It's also somewhat wobbly which is dangerous in traffic or confined
spaces. Don't do it.

See: http://sheldonbrown.com/starting.html

> 2) Forks on fixed gear bikes with a front brake have a higher rate of
> breakage because there is an too much stress from the combination of the
> front wheel being driven by the fixed gear while the front brake is
> applied. I assume this is invalid because the rider is either not
> driving or actually braking with the fixed gear when braking with the
> hand brake.

That's a bunch of used cattle fodder.

Forks on fixed gear bikes _without_ front brakes have a higher rate of
breakage, cause they're more likely to crash into stuff!

Sheldon "One For Two" Brown
+-------------------------------------------------------------+
| Give a man a fire, and he will stay warm for a day. |
| Set a man on fire, he stays warm for the rest of his life. |
+-------------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

David L. Johnson

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Jan 22, 2004, 8:26:31 PM1/22/04
to
On Thu, 22 Jan 2004 18:03:06 -0800, Jay Hill wrote:

>
> I've heard the following two arguments from people who worked in bike
> shops, and I assume they aren't valid, but I wonder enough to not
> dismiss them immediately, especially the second one.

I'll try to take care of that....


>
> 1) Do not mount a bicycle like a horse, by putting a foot in the left
> pedal and swinging the right leg over the seat to the other pedal.
> Allegedly this is bad because it puts too much stress on the bottom
> bracket. I assume this is invalid because the wheels' spokes will flex
> enough to absorb some of the stress, and besides that the bottom bracket
> is strong enough that it doesn't matter.

I've never done this, but if a bottom bracket can take the strain of
climbing a steep hill in too-high a gear, as I often encounter on my fixed
gear, I can't imagine this would be a problem.

>
> 2) Forks on fixed gear bikes with a front brake have a higher rate of
> breakage because there is an too much stress from the combination of the
> front wheel being driven by the fixed gear while the front brake is
> applied.

When you are applying the brake you are _not_ driving the rear wheel. The
gear does not drive the wheel, your legs do. When you hit the brake, you
are simultaneously applying back-pressure on the pedals. I don't think
it's natural not to do so under those conditions. But you certainly are
not pushing forward, and that is the only way the "fixed gear" can be
driving anything.

I also have one of those supposedly weak real track forks. I'll let you
know if I break it. It's only 34 years old now. The round cross-section
may not geometrically be the strongest against braking forces, but they
were sturdily built.

If fixed-gear bikes tend to have more broken forks (not resulting from
accidents), it would be because they are often built out of old frames of
questionable quality.

--

David L. Johnson

__o | If all economists were laid end to end, they would not reach a
_`\(,_ | conclusion. -- George Bernard Shaw
(_)/ (_) |

DiabloScott

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Jan 22, 2004, 9:52:25 PM1/22/04
to
Jay Hill wrote:
> I've heard the following two arguments from people who worked in bike
> shops, and I assume they aren't valid, but I wonder enough to not
> dismiss them immediately, especially the second one.
> 1) Do not mount a bicycle like a horse, by putting a foot in the left
> pedal and swinging the right leg over the seat to the other pedal.
> Allegedly this is bad because it puts too much stress on the bottom
> bracket. I assume this is invalid because the wheels' spokes will
> flex enough to absorb some of the stress, and besides that the bottom
> bracket is strong enough that it doesn't matter.

Are you talking about clipping in the left foot and then pushing off so
you're swinging the right leg over while you're on the move? I've been
doing that my entire cycling life. There's no more graceful way to mount
a bike in my opinion - I even try to keep my toes pointed and knee
straight like an olympic gymnast while I do it.

Or maybe you're talking about holding onto a wall or parking meter
while you swing over your leg? I could see how that's more stressful on
the wheels.

--


Doug

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Jan 22, 2004, 10:27:19 PM1/22/04
to

"Rick Onanian" <spam...@cox.net> wrote in message
news:snp0101nlrshvabk7...@4ax.com...

> On Thu, 22 Jan 2004 18:03:06 -0800, Jay Hill <jsh...@stic.net>
> wrote:
> >1) Do not mount a bicycle like a horse, by putting a foot in the left
> >pedal and swinging the right leg over the seat to the other pedal.
>
> Why would you want to do this, anyway?
>
> Either the bike goes forward from the foot on the pedal, or you use
> the brake and have to trackstand while not standing still, or the
> pedal is at the bottom of the stroke and is barely different from
> keeping that foot on the ground.

How about to mount and dismount a cyclocross bike on the fly?


Jose Rizal

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Jan 22, 2004, 10:47:55 PM1/22/04
to
Sheldon Brown:

> Jay Hill wrote:

> > 1) Do not mount a bicycle like a horse, by putting a foot in the left
> > pedal and swinging the right leg over the seat to the other pedal.
> > Allegedly this is bad because it puts too much stress on the bottom
> > bracket. I assume this is invalid because the wheels' spokes will flex
> > enough to absorb some of the stress, and besides that the bottom bracket
> > is strong enough that it doesn't matter.
>
> This doesn't bother the bottom bracket, but is very stressful to the
> wheels. Bicycle wheels are very strong against radial loads, but quite
> weak against side loads.
>
> It's also somewhat wobbly which is dangerous in traffic or confined
> spaces. Don't do it.

Fair enough when in traffic, but I see sprinters do the wobble all the
time, with the bike leaning from side to side; if so, why is lateral
loading not an issue with their wheels, or is it?


Alex Rodriguez

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Jan 22, 2004, 11:30:07 PM1/22/04
to
In article <40106459$0$43856$39ce...@news.twtelecom.net>, jsh...@stic.net
says...

How do people think up this stuff? 1 is obviously wrong. 2 makes half
sense. The front wheel is not driven, so it makes no sense. What probably
does happen is that someone drills a fork that did not come drilled for a
front brake. They did not drill the hole properly and that causes the
fork to break. Even if they do drill the hole properly, the crown may not
be designed to take braking forces, so it maky break.
---------------
Alex


Mike S.

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Jan 22, 2004, 11:32:20 PM1/22/04
to

"Doug" <dou...@REMOVE.earthlink.net> wrote in message
news:rw0Qb.20519$q4.1...@newsread3.news.atl.earthlink.net...
To dismount you're standing on your left pedal briefly. To re-mount you
jump onto the saddle then try and find your pedals as you're rolling along.

Doesn't really apply except for that brief period dismounting. Generally
you're coasting along balanced, not trying to start moving.

Mike

Sheldon Brown

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Jan 22, 2004, 11:48:59 PM1/22/04
to
Jay Hill wrote:
>
>
>>>1) Do not mount a bicycle like a horse, by putting a foot in the left
>>>pedal and swinging the right leg over the seat to the other pedal.
>>>Allegedly this is bad because it puts too much stress on the bottom
>>>bracket. I assume this is invalid because the wheels' spokes will flex
>>>enough to absorb some of the stress, and besides that the bottom bracket
>>>is strong enough that it doesn't matter.

I replied:

>>This doesn't bother the bottom bracket, but is very stressful to the
>>wheels. Bicycle wheels are very strong against radial loads, but quite
>>weak against side loads.
>>
>>It's also somewhat wobbly which is dangerous in traffic or confined
>>spaces. Don't do it.

Jose Rizal asked in his unusual font:

> Fair enough when in traffic, but I see sprinters do the wobble all the
> time, with the bike leaning from side to side; if so, why is lateral
> loading not an issue with their wheels, or is it?

They're straddling the bike. They lean it, but can't lean it all that
far without bumping their legs on the top tube.

Someone standing to one side of the bike has to lean it quite a bit
farther it make it balance.

Sheldon "A Matter Of Degrees" Brown
+-----------------------------------------+
| He not busy being born is busy dying. |
| -Bob Dylan |
+-----------------------------------------+

Qui si parla Campagnolo

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Jan 23, 2004, 8:51:08 AM1/23/04
to
jshill-<< I assume they aren't valid >><BR><BR>

<< I've heard the following two arguments from people who worked in bike
shops, >><BR><BR>

<< 1) Do not mount a bicycle like a horse, by putting a foot in the left
pedal and swinging the right leg over the seat to the other pedal.
Allegedly this is bad because it puts too much stress on the bottom
bracket. >><BR><BR>

<< 2) Forks on fixed gear bikes with a front brake have a higher rate of
breakage because there is an too much stress from the combination of the
front wheel being driven by the fixed gear while the front brake is
applied >><BR><BR>

JGBSM....why the bike biz is in trouble.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"

Clarke White

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Jan 23, 2004, 10:08:48 AM1/23/04
to
I have conducted an informal study over the years to determine why some
riders have chronic spoke breakage problems and other riders don't. I
observed that ALL of my customers who were having chronic spoke breakage
problems mounted their bikes like a horse. Those customers who I convinced
to mount their bikes "normally" have had either reduced incidence or no
spoke breakage.
I know, unscientific but anecdotal evidence does seem to point towards
mounting the bike this way is not kind to the wheels.
Clarke
www.clarkecycles.com

wle

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Jan 23, 2004, 10:19:15 AM1/23/04
to
> >
> >1) Do not mount a bicycle like a horse, by putting a foot in the left
> >pedal and swinging the right leg over the seat to the other pedal.
> >Allegedly this is bad because it puts too much stress on the bottom
> >bracket. I assume this is invalid because the wheels' spokes will flex
> >enough to absorb some of the stress, and besides that the bottom bracket
> >is strong enough that it doesn't matter.

why would you do that?

what i always do is

lean the bike towards me a little [easier]
lift leg over bike
lower leg
raise bike
now i am standing over the top tube [same as waiting at a stop sign now]
wait til ready to take off
clip in on left foot, raise to about 3:00, pedal off
clip in right foot.

what is the necessity for mounting, clipping in,
and taking off right away?

wle.

Zog The Undeniable

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Jan 23, 2004, 1:12:16 PM1/23/04
to
Jay Hill wrote:

They both sound pretty barking to me. (1) is common practice among
cyclo-crossers and the loads are probably similar to those in a bunch
sprint where the bike is thrown around under the rider.

(2) sounds like total codswallop because no-one in their right mind
would pedal and brake at the same time. Moreover, pedalling only
produces a few pounds of forward force because of gearing and the size
of the rear wheel; this is insignificant compared to the force needed to
scrub off your momentum at the traffic lights.

Pedalling at a fairly furious 300W and a steady 22mph translates to a
propelling force of only 30N or about 7lbf at the rear wheel. A
smartish stop from the same speed, over a distance of 15 metres,
requires a braking force of 66lbf, using a total mass of 90kg/198lb.
That's almost an order of magnitude more. The fork won't be troubled
even if you do keep pedalling.

Werehatrack

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Jan 23, 2004, 1:24:07 PM1/23/04
to
On Fri, 23 Jan 2004 15:08:48 GMT, "Clarke White" <sxb...@yahoo.com>
may have said:

>> I've heard the following two arguments from people who worked in bike
>> shops, and I assume they aren't valid, but I wonder enough to not
>> dismiss them immediately, especially the second one.
>>

>> 1) Do not mount a bicycle like a horse...


>
>I have conducted an informal study over the years to determine why some
>riders have chronic spoke breakage problems and other riders don't. I
>observed that ALL of my customers who were having chronic spoke breakage
>problems mounted their bikes like a horse. Those customers who I convinced
>to mount their bikes "normally" have had either reduced incidence or no
>spoke breakage.
>I know, unscientific but anecdotal evidence does seem to point towards
>mounting the bike this way is not kind to the wheels.
> Clarke
> www.clarkecycles.com

Besides, getting on the right way is just plain easier, unless the top
tube is at a gonadally-hazardous altitude.

Qui si parla Campagnolo

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Jan 24, 2004, 9:26:08 AM1/24/04
to
clark-<< I have conducted an informal study over the years to determine why

some
riders have chronic spoke breakage problems and other riders don't. I
observed that ALL of my customers who were having chronic spoke breakage
problems mounted their bikes like a horse. >><BR><BR>

I think the problem is with the wheelbuilder, not mounting a bike like a horse.
I cannot believe the side loads on a wheel when getting on this way are more
severe that when riding aggressivley. Stress relieving and taking windout out
of the spokes stress a wheel more as well...and that sure doesn't cause spoke
breakeage.

whitfit

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Jan 24, 2004, 2:41:21 PM1/24/04
to
w...@mailinator.com (wle) wrote in message news:<60402c15.04012...@posting.google.com>...

The same as Sheldon and others reccommend. I agree for a loaded bike,
and it is an essential thing to know. However, the rest of the time,
LIGHTEN UP!!!!!!! I often mount my fixie by pushing off and jumping
on the saddle. Then find the swinging pedals. Or the horse mount.
In one smooth motion and while moving, I doubt the stresses on the
wheels are that high.

Whitfit.

John Thompson

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Jan 24, 2004, 6:08:12 PM1/24/04
to
On 2004-01-23, Zog The Undeniable <g...@hhh.net> wrote:

> Jay Hill wrote:
>
>> 2) Forks on fixed gear bikes with a front brake have a higher rate of
>> breakage because there is an too much stress from the combination of the
>> front wheel being driven by the fixed gear while the front brake is
>> applied. I assume this is invalid because the rider is either not
>> driving or actually braking with the fixed gear when braking with the
>> hand brake.

> (2) sounds like total codswallop because no-one in their right mind

> would pedal and brake at the same time.

Quite true. About the only (weak) justification for (2) I can think of is
that most "real" track bikes have round fork blades while road bikes have
oval blades elongated in axis of the wheels. Presumably this may make
such blades more able to handle braking forces along that axis, but I
don't know if it is anything significant.


--

-John (JohnTh...@new.rr.com)

bb...@operamail.com

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Jan 24, 2004, 7:56:50 PM1/24/04
to
On 24 Jan 2004 14:26:08 GMT, vecc...@aol.com (Qui si parla
Campagnolo) wrote:

---clip


>
>I think the problem is with the wheelbuilder, not mounting a bike like a horse.
>I cannot believe the side loads on a wheel when getting on this way are more
>severe that when riding aggressivley. Stress relieving and taking windout out
>of the spokes stress a wheel more as well...and that sure doesn't cause spoke
>breakeage.
>
>Peter Chisholm
>Vecchio's Bicicletteria
>1833 Pearl St.
>Boulder, CO, 80302
>(303)440-3535
>http://www.vecchios.com
>"Ruote convenzionali costruite eccezionalmente bene"

------------------

I think you're right, Peter.

As a modest 7k rider of short rides, 180 pound "horsemounter" , I can
reflect on no spoke breakage during the past 20k mi, mainly on 27"
aluminum wheels with straight-guage spokes, also 700c's. I
stress-relieve, tension and true my own; and prior I'd break an
occasional driveside spoke on ordinary, untreated wheels.

One may conjure a mental image of excessive bike-lean in the
horsemount process, but in fact the bike remains close to vertical.
Both hands on the top bars, the upper torso is moves forward and
rightward over the top tube to compensate for the right leg still on
the bike left. And one doesn't jump on the left pedal, instead a
smooth step. The weight distribution favors the front wheel.

Give it a try and observe -- weight placed as preliminary to a hand
stand on the front wheel as it slowly moves.

If there are additional stresses on the spokes/wheels, they don't show
themselves to me. And one would expect at least a rare spoke snap
during the mounting -- anyone observe one of these?

I enjoy horsemounting because it's fun, easy, fast, natural (to me).

Otherwise it's clomp, clomp, straddle, step & go -- mechanical and
without grace. 'jus my opinion.

Bruce Ball
Colo Spgs

jobst....@stanfordalumni.org

unread,
Jan 24, 2004, 8:08:23 PM1/24/04
to
Jay Hill writes:

[as a cause for broken spokes]

> 1) Do not mount a bicycle like a horse, by putting a foot in the
> left pedal and swinging the right leg over the seat to the other
> pedal.

Please explain how this can have any effect considering that I can
coast down a road standing on one pedal while leaning as far out to
one side as I like with no spoke failures. Noting that spoke failures
are 99.44% fatigue failures if they didn't occur at the first loading
or a when a foreign object snagged a spoke, what effect does mounting
the bicycle have on the endurance of spokes?

This is one of the most bizarre claims I have heard about the spoked
bicycle wheel. Having never heard it before, I wonder what sort of
underground passes along such myth and lore.

Jobst Brandt
jobst....@stanfordalumni.org

Jim Adney

unread,
Jan 25, 2004, 2:26:50 PM1/25/04
to
On Thu, 22 Jan 2004 20:19:31 -0500 Sheldon Brown
<Capt...@sheldonbrown.com> wrote:

>This doesn't bother the bottom bracket, but is very stressful to the
>wheels. Bicycle wheels are very strong against radial loads, but quite
>weak against side loads.

Sorry Sheldon, but I have to take issue with you on this one. I agree
that side loads on the bike certainly do put some of the most extreme
loads on the spokes, but it is easy to ride along in a straight line
while tilting the bike over way past the spoke angle. I've done this a
number of times, just to see if it causes any problems and it never
has.

I also commonly mount my bike single sided, swinging my right leg over
the frame after I'm under way. I often dismount the same way, coasting
the last 30 yards on one side of the bike.

I haven't had a random broken spoke in about 35 years, since I got rid
of that Normandy rear hub with the left flange offset all the way to
the outside, so far that I couldn't put any tension in those spokes.
That was an awful hub, but it taught me an important lesson: Loose
spokes are a problem.

-
-----------------------------------------------
Jim Adney jad...@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------

Carl Fogel

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Jan 25, 2004, 2:48:40 PM1/25/04
to
jobst....@stanfordalumni.org wrote in message news:<bGEQb.10617$XF6.2...@typhoon.sonic.net>...

Dear Jobst,

I expect that you're right, but now I want to
know what actually happens to the spokes when
a rider stands on one pedal and leans way over
while coasting straight down the road.

As the pre-tensioned left and right side spokes
pass under the axle, they lose tension, right?

But if I'm standing on the left pedal with the
bike and wheel leaning way over to the right,
what does that do to the spokes?

I looked at "The Bicycle Wheel," where you go
over lateral stiffness and later showed your
testing rig for demonstrating that tying and
soldering are merely decorative, but I'm not
sure how to apply what you wrote.

I think that the left side spokes should gain
tension with the wheel leaning over to the right,
but do they all gain tension equally? Or does
the force act only through the rim just above
the contact patch? Either way, does this gain
in tension cancel out the loss of tension on
the left side spokes rolling under the axle?

Similarly, do all the right-side spokes lose
tension because the wheel is leaning to the
right, or just the ones on the bottom? And
could the bottom ones get into trouble because
the loss in tension from the sideways leaning
is added to the loss in tension from the
normal load?

Here's a crude view from the rear of what
I'm wondering about:
top
rim
do all left-side / /
spokes gain tension / /
due to lean --> / / <--do all right-side spokes
or just a few / / lose tension due to lean?
lower left-side / / or just a few lower right-side spokes?
spokes? left hub right
/ /
can left-side / /
tension gain / /
cancel normal / / <--can right-side tension loss
lowermost-spoke / / plus normal lowermost-spoke tension loss
tension loss? / / get out of hand?
rim
-------------ground and contact patch

I suspect that even with a heavy rider the
sideways load is much less than the vertical
load, but I'm still curious about what the
leaning does to the spoke tension--do all spokes
on one side change tension equally, or just the
ones down near the contact patch?

Carl Fogel

Werehatrack

unread,
Jan 25, 2004, 6:52:11 PM1/25/04
to
On Sat, 24 Jan 2004 17:56:50 -0700, bb...@operamail.com may have said:

>I enjoy horsemounting because it's fun, easy, fast, natural (to me).
>
>Otherwise it's clomp, clomp, straddle, step & go -- mechanical and
>without grace. 'jus my opinion.

Mileages vary.

For me, the right leg goes over the top onto the pedal (which has been
brought to the 1 o'lock position beforehand) and then the takeoff
proceeds as the left foot leaves the ground. (Conventional pedals, no
clips or cleats.)

I've done a horse-mount sometimes, but I just prefer the other way.
Everyone finds the way that work for them.

Werehatrack

unread,
Jan 25, 2004, 6:57:03 PM1/25/04
to
On Sun, 25 Jan 2004 01:08:23 GMT, jobst....@stanfordalumni.org may
have said:

[snippage]


>This is one of the most bizarre claims I have heard about the spoked
>bicycle wheel. Having never heard it before, I wonder what sort of
>underground passes along such myth and lore.

Probably the same variety that propagates urban legends of the more
common sorts, like the currently-popular "Terrorists may be at your
door in UPS uniforms" scaremail.

I struck me (after the fact) that the whole "mounting wrong can cause
spoke breakage" assertion had an apparent flaw; if the side forces
were that large, would it not be true that people would be turning
their wheels into tacos by that practice? Yet they are not.

bb...@nosoperamail.com

unread,
Jan 25, 2004, 8:31:24 PM1/25/04
to
On Sun, 25 Jan 2004 23:52:11 GMT, Werehatrack
<rau...@earthWEEDSlink.net> wrote:

>On Sat, 24 Jan 2004 17:56:50 -0700, bb...@operamail.com may have said:
>
>>I enjoy horsemounting because it's fun, easy, fast, natural (to me).
>>
>>Otherwise it's clomp, clomp, straddle, step & go -- mechanical and
>>without grace. 'jus my opinion.
>
>Mileages vary.
>
>For me, the right leg goes over the top onto the pedal (which has been
>brought to the 1 o'lock position beforehand) and then the takeoff
>proceeds as the left foot leaves the ground. (Conventional pedals, no
>clips or cleats.)
>
>I've done a horse-mount sometimes, but I just prefer the other way.
>Everyone finds the way that work for them.

---------------

I might do the same but the 3-3/4" gain on the left pedal stepup
allows for easier clearance on the seat legover with my short legs.

Fellow rider of the true clipless; i.e., pedals without clips.

Bruce Ball

bb...@nosoperamail.com

unread,
Jan 25, 2004, 8:44:37 PM1/25/04
to
On 25 Jan 2004 11:48:40 -0800, carl...@comcast.net (Carl Fogel)
wrote:

---------- clip

>But if I'm standing on the left pedal with the
>bike and wheel leaning way over to the right,
>what does that do to the spokes?
>

---------- clip

Pardon for butting in, but I wondered the same and pondered for a
time, suspecting the left upper spokes might increase in tension.

However, a simple ping test reveals the right driveside upper spokes
increase in tension. Simply lean the bike to the right, apply force
to the left pedal, pluck the spokes, note the rise in pitch/frequency.

Bruce Ball

Carl Fogel

unread,
Jan 26, 2004, 2:27:05 AM1/26/04
to
bb...@NOSoperamail.com wrote in message news:<8jr810lu45alsohpj...@4ax.com>...

Dear Bruce,

You're not butting in at all. I'm delighted to
hear anyone, particularly when they're kind
enough not to say that I had it backwards.

I just looked over my babbling and strongly
suspect that I had it completely backwards.

With the wheel leaning over to the right, some
or all left-side spokes should lose tension,
while some or all right spokes should gain
tension.

Or so I think now that you've politely pointed
out yet another of my imbecilities. I appreciate
it. (Poor Jobst may well be grinding his teeth
and wondering what he ever did to deserve such
bizarre questions carefully asked backward.)

Thanks,

Carl Fogel

jobst....@stanfordalumni.org

unread,
Jan 26, 2004, 8:25:10 PM1/26/04
to
Carl Fogel writes:

>> [as a cause for broken spokes]

>>> 1) Do not mount a bicycle like a horse, by putting a foot in the
>>> left pedal and swinging the right leg over the seat to the other
>>> pedal.

>> Please explain how this can have any effect considering that I can
>> coast down a road standing on one pedal while leaning as far out to
>> one side as I like with no spoke failures. Noting that spoke
>> failures are 99.44% fatigue failures if they didn't occur at the
>> first loading or a when a foreign object snagged a spoke, what
>> effect does mounting the bicycle have on the endurance of spokes?

>> This is one of the most bizarre claims I have heard about the
>> spoked bicycle wheel. Having never heard it before, I wonder what
>> sort of underground passes along such myth and lore.

> I expect that you're right, but now I want to know what actually


> happens to the spokes when a rider stands on one pedal and leans way
> over while coasting straight down the road.

I think you'll find that in "the Bicycle Wheel" with a diagram of
tension shift from one side to the other. From cosine error, the
characteristics are not entirely symmetrical although for small
displacements, the instantaneous lateral compliance is the same.

> As the pre-tensioned left and right side spokes pass under the axle,
> they lose tension, right?

> But if I'm standing on the left pedal with the bike and wheel
> leaning way over to the right, what does that do to the spokes?

> I looked at "The Bicycle Wheel," where you go over lateral stiffness
> and later showed your testing rig for demonstrating that tying and
> soldering are merely decorative, but I'm not sure how to apply what
> you wrote.

Look at the lateral stiffness diagram and observe the curves of spoke
tension and lateral force for a given displacement.

> I think that the left side spokes should gain tension with the wheel
> leaning over to the right, but do they all gain tension equally?

This is a section view considering one typical spoke from each side.
Depending on the cross section of the rim, this gets distributed over
more than just one opposing pair.

> Or does the force act only through the rim just above the contact
> patch? Either way, does this gain in tension cancel out the loss of
> tension on the left side spokes rolling under the axle?

> Similarly, do all the right-side spokes lose tension because the
> wheel is leaning to the right, or just the ones on the bottom? And
> could the bottom ones get into trouble because the loss in tension
> from the sideways leaning is added to the loss in tension from the
> normal load?

I think you are pulling my leg, so to speak. Look at the other
displacement curves to get a feel for load distribution. Wheel
collapse diagrams also give a hint to what is occurring.

> Here's a crude view from the rear of what
> I'm wondering about:
> top
> rim
> do all left-side / /
> spokes gain tension / /
> due to lean --> / / <--do all right-side spokes
> or just a few / / lose tension due to lean?
> lower left-side / / or just a few lower right-side spokes?
> spokes? left hub right
> / /
> can left-side / /
> tension gain / /
> cancel normal / / <--can right-side tension loss
> lowermost-spoke / / plus normal lowermost-spoke tension loss
> tension loss? / / get out of hand?
> rim
> -------------ground and contact patch

The spoked wheel is not a rigid disk as you picture it. Its lateral
deflections are similar to its radial deflections, local to the point
of loading. Even if it were a rigid disk, you picture shows that at
least at the horizontal diameter, there would be no change, but that
model is unreal anyway.

> I suspect that even with a heavy rider the sideways load is much
> less than the vertical load, but I'm still curious about what the
> leaning does to the spoke tension--do all spokes on one side change
> tension equally, or just the ones down near the contact patch?

Side loads are insignificant in nearly all riding. That is why
10-speed clusters, and their far narrower flange spacing that
tradition, work.

The subject comes up often from track riders who believe that there
are enormous side loads while speeding around the banking of a track
as they visualize their entire weight is pressing only down while the
wheels are contacting the "wall".

Jobst Brandt
jobst....@stanfordalumni.org

jobst....@stanfordalumni.org

unread,
Jan 26, 2004, 8:55:08 PM1/26/04
to
Bill Ball writes:

>> But if I'm standing on the left pedal with the bike and wheel
>> leaning way over to the right, what does that do to the spokes?

> Pardon for butting in, but I wondered the same and pondered for a


> time, suspecting the left upper spokes might increase in tension.

> However, a simple ping test reveals the right driveside upper spokes
> increase in tension. Simply lean the bike to the right, apply force
> to the left pedal, pluck the spokes, note the rise in pitch/frequency.

I think you can find that experiment in "the Bicycle Wheel" where
wheel collapse from a lateral load at the ground is described. I
still have the wheels that was used to verify that theoretical
analysis of why a wheel forms a "taco" when it is overloaded laterally
at one location.

Jobst Brandt
jobst....@stanfordalumni.org

Tom Sherman

unread,
Jan 26, 2004, 9:44:42 PM1/26/04
to
jobst....@stanfordalumni.org wrote:

> Please explain how this can have any effect considering that I can
> coast down a road standing on one pedal while leaning as far out to
> one side as I like with no spoke failures. Noting that spoke failures
> are 99.44% fatigue failures if they didn't occur at the first loading

> or a when a foreign object snagged a spoke....

And so the correlation between the soap content of Ivory [TM] and the
failure mode of spokes is made. ;)

Tom Sherman - Quad Cities

jobst....@stanfordalumni.org

unread,
Jan 27, 2004, 12:18:45 AM1/27/04
to
Carl Fogel writes:

>> [as a cause for broken spokes]

>>> 1) Do not mount a bicycle like a horse, by putting a foot in the
>>> left pedal and swinging the right leg over the seat to the other
>>> pedal.

>> Please explain how this can have any effect considering that I can
>> coast down a road standing on one pedal while leaning as far out to
>> one side as I like with no spoke failures. Noting that spoke
>> failures are 99.44% fatigue failures if they didn't occur at the
>> first loading or a when a foreign object snagged a spoke, what
>> effect does mounting the bicycle have on the endurance of spokes?

>> This is one of the most bizarre claims I have heard about the
>> spoked bicycle wheel. Having never heard it before, I wonder what
>> sort of underground passes along such myth and lore.

> I expect that you're right, but now I want to know what actually


> happens to the spokes when a rider stands on one pedal and leans way
> over while coasting straight down the road.

> As the pre-tensioned left and right side spokes pass under the axle,
> they lose tension, right?

You can review this in the diagrams for lateral loading in "the
Bicycle Wheel" where lateral force and stiffness is shown for a cross
section of the wheel at the load point.

> But if I'm standing on the left pedal with the bike and wheel
> leaning way over to the right, what does that do to the spokes?

> I looked at "The Bicycle Wheel," where you go over lateral stiffness
> and later showed your testing rig for demonstrating that tying and
> soldering are merely decorative, but I'm not sure how to apply what
> you wrote.

I don't see how tying and soldering got into this but what you read is
correct, it has no effect on wheel strength.

> I think that the left side spokes should gain tension with the wheel
> leaning over to the right, but do they all gain tension equally? Or
> does the force act only through the rim just above the contact
> patch? Either way, does this gain in tension cancel out the loss of
> tension on the left side spokes rolling under the axle?

> Similarly, do all the right-side spokes lose tension because the
> wheel is leaning to the right, or just the ones on the bottom? And
> could the bottom ones get into trouble because the loss in tension
> from the sideways leaning is added to the loss in tension from the
> normal load?

Look at the diagram showing wheel collapse with a side load applied at
one point on the wheel. All the diagrams are of naturally loaded
wheels as they would be used so the load is applied at the ground
contact point.

> Here's a crude view from the rear of what
> I'm wondering about:
> top
> rim
> do all left-side / /
> spokes gain tension / /
> due to lean --> / / <--do all right-side spokes
> or just a few / / lose tension due to lean?
> lower left-side / / or just a few lower right-side spokes?
> spokes? left hub right
> / /
> can left-side / /
> tension gain / /
> cancel normal / / <--can right-side tension loss
> lowermost-spoke / / plus normal lowermost-spoke tension loss
> tension loss? / / get out of hand?
> rim
> -------------ground and contact patch

Wheels are not rigid disks and do not respond to side loads as your
diagram suggests. Besides, the wheel collapse diagram shows that the
rim deflects to the same side on top as at the ground contact patch.
That is how the "taco" or saddle failure occurs. I still have the
wheel that was made into a taco to verify the theoretical explanation
of side load failure.

> I suspect that even with a heavy rider the sideways load is much
> less than the vertical load, but I'm still curious about what the
> leaning does to the spoke tension--do all spokes on one side change
> tension equally, or just the ones down near the contact patch?

Review the relevant parts of the book. It's all there.

Jobst Brandt
jobst....@stanfordalumni.org

Werehatrack

unread,
Jan 27, 2004, 10:55:42 AM1/27/04
to

It's really an amazing coincidence, innit?

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