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Introduction: Bicycle Design
Why Upright Bikes?
Why Recumbents Cost More
Types of Recumbents
Seat Height
Handlebars
How Much To Spend?
The Importance of Wheels
Types of Wheels
The Importance of Weight
Frame Materials
Frame Alignment
Parts, Derailleurs etc
Brakes
Suspension
Are Recumbents Invisible?
Acclimatizing to a Recumbent
Hills on a Recumbent
Clip-On Pedals
Racks & Mudguards
Bicycle Trailers
Trikes
How to Ride a Tandem
Credit Card Touring
Information Sources
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The Importance of Good Wheels

On any bicycle it is important to have good wheels. Bad ones can slow the bicycle, give bad performance and break spokes prematurely. Good wheels are doubly important on a tandem where much more weight and speed are being carried by the wheels and no risks should be taken.

Most new bicycles from large factories are delivered with less than stellar wheels that are partially or wholly built-up by wheel-building machines. Bicycle shops usually do not have the time or the money to tune-up the factory-built wheels and most people seem to tolerate the imperfect performance of factory-built wheels.

On a tandem, less than perfectly-built wheels should not be tolerated. Builders of high-quality tandems generally supply their bicycles with high-quality wheels that have been finished by a skilled (human) wheelbuilder.

A good tandem wheel consists of a high-quality hub that is specifically designed for tandem use, a high-quality rim designed for tandem use and double-butted or triple-butted spokes made by a high-quality spoke supplier such as DT Swiss AG. Butted spokes are slightly lighter but they are used because they are more durable than straight-gauge spokes (because of the desireable spring characteristics of butted spokes). The spokes must be of a diameter that is appropriate for tandems.

Tandem wheels should have more spokes than single bike wheels. The larger number of spokes make the wheel stronger, more durable and less likely to go out of true. Single bike wheels have 28, 32 or 36 spokes. Tandem wheels have 40 or 48 spokes. For instance, a tandem team with a weight of 300 pounds and touring equipment should use wheels with 48 spokes to avoid wheel-maintenance issues. Some heavy racing teams use 48 spokes for durability and reliability even though the extra spokes add rotational inertia that slows the acceleration of the bicycle wheel (and therefore the bicycle).

Bicycle wheels undergo minute accelerations through each pedal stroke so, in theory, low rotational inertia should be fairly important. In practice, on a tandem, two cyclists tend to even out the power curve on the pedal stroke (especially when the two sets of pedals are placed out of phase) so that the minor accelerations may not be important and the added weight of the extra spokes may not be important.

Adding spokes to a wheel increases its radial and lateral stability. A wheel that has more spokes can be have a noticeably less mushy feel to it because it more directly transmits power from the cyclist to the pavement.

Some people have the notion that increasing the number of spokes will increase the aerodynamic resistance of the wheel. That is true but the aerodynamic resistance of two cyclists on two tandem wheels will be half that of two cyclists on four single bike wheels and the aerodynamic resistance on a bicycle wheel is only measurably significant at speeds above 30 mph (50 kmh) anyway. Besides, we are only talking about a 20% increase in the number of spokes.

There is no legitimate reason for most people to avoid 48-spoked 26” and 700C wheels. 20-inch wheels used on recumbents and some upright tandems have different strength characteristics and do not require as many spokes as 26” and 700C wheels.

Bicycle wheels are technological marvels of tremendous complexity. They are incredibly light yet, if they are built properly, they can endure very strong radial, lateral and torsional forces.

Wheelbuilding is an art that has serious consequences to the strength, stability and durability of the wheel. The wheel must be built to be radially and laterally true and symmetric and the spoke tension must be even and uniform, except on the non-drive side of the rear wheel. On the non-drive side of the rear wheel the spokes are only tensioned to about 65% of the tension of the spokes of the freewheel side of the rear wheel on rear wheels that are “dished”. Dished wheels have shorter spokes on the freewheel side and attach to the hub closer to the midpoint of the rear axle than the spokes on the non-drive side of the wheel.

Uniform and consistent spoke tension is so important that many skilled wheelbuilders rely on a very sensitive dial tensiometer to make up for inconsistencies in human judgement. Wheels that are built with inadequate tension will go out of true and spokes will eventually break.

The skilled wheelbuilder will also ensure that no spokes are “wound up” when the wheel is finished. Spokes that are twisted along their length contain stored torsional energy and may loosen and cause the wheel to go out of true or cause the spoke to break when it becomes loose. The wheel will be hand stress-relieved and re-trued by the builder before it is sent to the customer.

Wheelbuilding is often undertaken by enthusiastic recreational cyclists. Many people gain great satisfaction in the act of building a wheel that can be a masterpiece compared to the factory-built wheel. Even a rudimentary knowledge of wheel truing learned from a general text on cycle repair will save the bicycle owner a trip to the bicycle shop when wheels go out of true.

Two good books on wheelbuilding are:

The Bicycle Wheel by Jobst Brandt, Avocet Inc, Palo Alto, California

The Art of Wheelbuilding by Gerd Schraner, Buonpane Publications, Denver, Colorado