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About Features and Rims - About Hubs and Spokes

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We all want good products. Good products have features, as do bad products. As soon as an aspect of a good product is recognized as a feature, that feature will be used as a false harbinger of quality in a lesser product. What may be worse is that a good product without that particular feature will then be overlooked or rejected. In addition there may be a quality aspect of a product that is not well known enough to have become featurized. The negation of this would be a feature that has nothing to do with product quality.

Here are some examples from the circle of rims:

First, a non-feature.
Rims are extrusions, like toothpaste or the stuff that comes out of the machine at the Dairy Queen. Ideally, a rim would be extruded from its die in a straight line (i.e. as a two dimensional figure) and then chopped and hooped, or vice versa. Most rims, however, are extruded onto a rotating drum as a helix, a three dimensional shape. Thus when it is chopped, it must be forced back into a plane, with the usual result of a hop at the joint of the rim. Perhaps if or when this aspect of quality becomes a feature we will refer to rims as being planar or non-planar.

False harbinger
The XYZ company makes machined side-wall rims but run their cutting tools into the ground, with the result that the braking surfaces of their rims are generally less even than the rims made by the UVW company, who frequently change their extrusion dies but dont machine the side-wall of their rims.

Needless feature
We need to make a wheel for a heavy rider who will use a wide tire and will put side forces on the wheel. Since we will be choosing a wide and heavy rim, the material will be thick, and eyelets in the rim may not be necessary to help distribute the force of spoke pull.

HUBS

Hubs are a very important component and minimizing their energy loss is very important. Fortunately for all of us, this occured about a century ago, and the total of all bearing friction losses account for less than one per cent of the rider's energy losses. But, hey, don't let a little physics stop anyone stop anyone from the pleasure of pride of ownership that can come from saving energy with a three hundred dollar pair of hubs. Of course the chain he cleans every week (dirty from last week's oil's dirt harvest) that was worn out a few months ago is sucking 5% of the rider's energy, instead of the usual 2.5%. Oops! we're supposed to be selling things here. Oh. If your hubs are not properly adjusted friction can increase manyfold. Somewhat more than 86% of hubs from both mail order houses and bike shops have not been properly adjusted with the principle result that they wear out in a fraction of their expected service life, as well as stealing a little more energy. These things are the usual result of what is called a 'factory adjustment' to 'allow for a break-in-period' meaning the bearings are set too tight (stealing a little more energy). Insufficient locking force between the cones and locknuts allowing a change in bearing play is the cause of the short service life. Even a cheap hub can be made more free-rolling than expensive sealed or cone-and-ball units though sometimes it will then be loose too(besides being annoying to some, the bearing wear will be greater). One popular and inexpensive track hub has been seen to last only one or two months when used by couriers at the 'factory setting'. In fact the balls in this hub are so cheap a good setting is not really possible. However if they are replaced with Grade 25 balls with some good grease they will usually last longer then the rim (well we said these were courier wheels). In the same vein a close reading of about 4000 repair tags collected from 1993 to 2001 shows many examples of an all-weather commuter's acera or stx hub, adjusted when new, outlasting weekend use xt and xtr hubs that were not adjusted. Whether one chooses sealed bearing or cone and ball hubs, the end user will not normally receive a quality product unless quality is present in each stage of that product's journey: design, manufacture, and delivery. One lesson here is that one can save considerable funds by choosing a medium price hub IF IT COMES WITH AN EXCELLENT DELIVERY.

Really, the worst thing one can say about modern hubs is about their abyssmal design in regard to enhancing wheel strength; the marketeers having once again been successful in featureizing and bragging about these deficiencies(e.g. a dishless hub with a bad bracing angle).

SPOKES
In past times some prodocers of spokes had the phrase 'spoke and wire' as part of their company name. Spokes are made from wires, it takes only a few more steps to turn a wire into a spoke. Also the reason spokes are measured by diameter in wire guage. The wire is formed by extrusion, pulled through a die and wound on a spool. The threads are pressure-rolled rather than cut; no metal is lost as the cut wire is compressed and deformed. Mild steel is strong and ductile enough to be made into wire, however it will rust away and fail. Zinc, cadmimum, and chrome plating is used to prevent this. Zinc and cadmimum plate will quickly dull but this oxidation is limited to he surface. A bike with new chrome spokes can be seen three blocks away on a sunny morning but a winter's commuting will leave them pitted. Most 'high quality' spokes used today are made of stainless steel. The finish is good and has staying power. Stainless steel is less ductile than mild steel and so stainless spokes snap easier under overloads. Except for some restorations, Derby King uses Swiss made DT stainless steel spokes in his wheels. They have an enlongation factor of 7%; that is they will fail when stretched to 107% of their length.
As a comparison, Wheelsmith stainless spokes have an enlongation factor of 4%.
Straight guage spokes are the strongest ones. A spoke with a butt, or thickening on the end, is known as a single butted spoke. A spoke with butts on both ends is called 'double butted'. Some spokes have three or four different diameters. All of these butted spokes are stronger for the weight, and weaker overall than straight guage spokes. Use of double butted spokes saves the weight of four spokes out of a 36 spoke wheel.

Experience and technical acumen enable Derby King to hand-pick usage-appropriate components in a way that transcends marketing mumbo-jumbo. This yields a finished product that is not only better, but in some cases less expensive.