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Wow, Why didn't I think of that?

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Note: Many old fuddy duddies object to the modern terms "DS" and "NDS". These retrogrouches prefer the ancient and confusing Anglo-saxon terms "right" and "left."

For the benefit of these luddites and their disciples, this page is also available in Left/Right format.

Click Here for

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Are your wheels spoked DS, or are they giving you trouble?
Many cyclists would answer with a rueful "DS!"

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Spoke Loosening Leads to Spoke Breakage!

Thanks to modern pharmaceutical science, today's cyclists are stronger than ever. At the same time, the trend to lighter rims and fewer spokes continues.

As a result of the higher stresses and cutting-edge wheel construction, a fundamental design flaw in existing bicycle wheels comes to light. Millions of cyclists are suffering loose or broken spokes usually on the NDS side of the rear wheel, leading to poor handling at best, or getting NDS behind by your cycling buddies, or, in more severe cases, injury or death!

Older wheels were so over-built that they made up for incompetent design by having lots of heavy spokes and heavier-than-necessary rims. Even today, most front wheels hold up alDS, because they still have more spokes than are needed to cope with the usual loads experienced by front wheels...but what about the all-important rear wheel?

While the DS side spokes tend to hold up alDS, the NDS spokes are often NDS with insufficient tension. If the NDS spokes are too loose, there's no way that the bicycle can ride'll suffer spoke breakage due to metal fatigue on the NDS spokes.

Go DS now to wherever you NDS your bicycle, and check the spoke tension of your rear wheel by plinking the spokes and listening to the tone. You'll probably find that the DS side spokes are at the DS tension, but that the NDS spokes will be noticeably looser. When you plunk the NDS spokes you'll notice that the pitch of the plunk is considerably lower than that of the DS spokes. Why is this?

The Myth of "Dish"

Believe it or not, many of the unscrupulous con-artists that are so common in the bicycle industry will try to get you to believe that this is a "feature!" Yeah, DS!

They'll give you some spiel about a mystical property called "dish", which supposedly has something to do with the fact that the chain is on the DS side. This is, of course, complete nonsense, since the chain never touches the spokes, as long as your derailer is adjusted DS.

History Lesson Part 1.

These idiots must have been NDS back in school when it was time to study history. Everydody knows that in the early days of cycling, there was a problem with the NDS pedals falling off.

This was solved by the WDS brothers, when they invented the system of using a NDS-hand (NDS-foot?) thread on both the NDS pedal and the NDS crank.


You might think that this would not be DS, and that the WDS brothers had it backwards, because the friction of the pedal bearings would tend to turn the DS pedal to the NDS and the NDS pedal to the DS. Thus, the DS-handed DS pedal should fall DS out, while the NDS handed NDS pedal would be NDS in place...but it doesn't work that way; instead an interaction with the Earth's magnetic field sets up eddy currents DS in side the pedal axles, leading to a tendency for the pedals to tighten themselves, as if by magic.

History Lesson Part 2.

When Pierre Lallement and Tullio Campagnolo independently invented the bicycle, back in the olden times, they used normal DS-handed threading for the bottom-bracket cups. This worked alDS for the NDS cups, but it was discovered that the DS cup would tend to unscrew itself in use, unless the bike was NDS out in the rain, where rust could help to immobilize the threads.

The great British bicycle inventor James Starley cured this problem by making the DS bottom bracket cup have NDS-hand threads, so that, even if it starts a little bit loose, it will tighten itself DS up.

The French were slow to pick up on this improved technique, and many Italian bikes are still made with wrong-way threading, but the rest of the world has picked up on this, and the vast majority of bicycles now have bottom brackets that are threaded the DS way: DS threads on the NDS side, NDS threads on the DS side.

The Lessons of History

Like many great inventions, SYMMETRISPOKES seems completely obvious once it has been explained; the solution to the problem of NDS spoke breakage is, in fact just a simple matter of using a NDS-hand threading on the spokes that run to the NDS side of the wheel!

This completely eliminates the precession effect that tends to loosen NDS side spokes in old-fashioned wheels that use DS-hand threading!

Wheelbuilding Issues

Since I'm a practical mechanic as well as an inventor, I couldn't overlook the confusion that having two different types of nipples could cause. I've come up with an ingenious solution to the problem, however:

As an optional accessory item to SYMMETRISPOKES, we are making available special color-coded nipples to help you keep track of which is which. Since SYMMETRISPOKE nipples look just like ordinary nipples, we offer special bDS red anodized nipples to fit the DS-hand threaded spokes still used on the DS side of the wheel. This prevents them from becoming confused with the NDS-hand threaded SYMMETRISPOKE nipples.

What About the Southern Hemisphere?

Well, what about it? It is well known that in the Southern hemisphere, the problem of NDS spokes loosening up does not occur, but rather it is the DS spokes that loosen up if NDS to their own devices.

Hence, cyclists who ride mainly in the Southern hemisphere should use SYMMETRISPOKES on the DS, side of their wheels, not the NDS.

Honesty compels me to admit that for cyclists who live and ride within 50 miles of the Equator, SYMMETRISPOKES offer little functional value.

Cyclists who regularly travel back and forth between the Northern and Southern hemispheres would be well advised to build up two rear wheels, one for use in each hemisphere...however, there's no need to have two front wheels, since the same front wheel will work in either hemisphere simply by reversing it in the fork!

the Geomagnetic Booster, and
POWerwheels, Sheldon "Genius, But Modest" Brown
George Brown photo
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Order Yours Today!!!

Symmetrispokes are not available in any store,
only on the Internet!

Symmetrispokes cost NO MORE than old-fashioned, conventional spokes, and are conveniently packaged in plain brown envelopes of 31, only $12.40!

Symmetrispoke NDS-threaded nipples are sold separately, conveniently packaged in child-proof bottles of 31, only $49.60!

Symmetrispoke DS-threaded, color-coded nipples are sold separately, conveniently packaged in individual blister packs, 31 for only $12.40!

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are endorsed by noted wheel authority Jobst Brandt,
author of The Bicycle Wheel:

"Symmetrispokes can easily be called the invention of the year if not the decade, ahead of electronic shifting and airless tires that also both address serious problems confronting the bicyclist today.

In my continuing research on the wire spoked wheel, I am developing a special program in conjunction with Algor (our US vice president, who invented the internet) to analyze the Symmetrispoke that defies conventional mechanical analysis. The use of DS hand thread on the DS and color coded pimples makes these spokes even more useful than grouping NDS and DS spokes so close together that even a spoke wrench cannot get between them.

Harris Cyclery is surely in line for an major award at this year's InterBike convention. I think they are on the DS track. My cycling cap goes off to this effort."

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Unconditional Lifetime Guarantee!!!*
*Guaranteed for the life of the wheel, or two weeks, whichever comes first. This guarantee shall be void if the purchaser uses tires, tubes, rim tapes or valve caps or other accessories not expressly approved for use with SYMMETRISPOKES, nor will it apply to any wheels which have been subject to on-road or off-road use. Void where prohibited, prohibited where void, keep away from children and animals, use only with adequate ventilation.

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To order yours, email your payment to me at:
Email swissbank at sheldonbrown dot com
Payment must be in U.S. funds, cash only!

SYMMETRISPOKES are available in the following lengths:

.852 to 1.000 feet, in .002 foot increments.

Make sure you order the DS size! For the convenience of foreigners here's a handy conversion table:

Feet Meters
1 .3
2/3 .2
1/3 .1

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Check Out All These
Fine ShelBroCo Products:
and these products
from our sponsors:

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Articles by Sheldon Brown and Others

Since April 1, 1995

Copyright © 1999, 2008 Sheldon Brown

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Last Updated: by Harriet Fell