Old 07-17-19, 04:00 PM
  #13  
cyccommute 
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Originally Posted by Carbonfiberboy
The most important things for touring wheel durability are deep, strong rims and correct and even spoke tension. Those rims look plenty strong.
(Sigh. Do I really want to go down this road? I don't want to but I guess I'll have to. Here goes...)

Even spoke tension? Yes. Correct spoke tension? What is that? Strong rims? What does that have to do with wheel strength?

Yes, by all means the spoke tension should be even and consistent. But show me a chart that tells a wheel builder what the "correct" spoke tension is. The variables are too many...what rim, how many spokes, what hubs, what spoke gauge, what spoke nipples, rider weight, rider use, etc?...for any rim manufacturer to give you a "correct" spoke tension. Even the tensions that they suggest are across an extremely broad range and I would take as more of a CYA on their part than a real number. The real number may exist but I really doubt it. I've been building wheels for 40 years and I have yet to find that elusive chart.

As for the rim, first, you can't tell by looking that the rim is strong or weak. That depends on the thickness of the metal and the number of spokes the rim is supposed to be laced to. The rim doesn't do much in terms of resisting the forces that are placed on a wheel because the metal used...aluminum...is soft and small changes in the configuration won't make that much difference. Deep rims might resist upward deflection slightly more than a shallow rim but most of the deep rims are also narrow rims which means they don't resist sideways deflections as well. Wide rims might resist sideways deflections but they don't do much to resist upward deflection. Basically, any rim out there is probably adequate for the (fairly easy) job that rims have to handle.

The real work done to make a wheel strong is done by the most overlooked part of the wheel...the spokes! Spokes do all the work to keep the rim from bending side-to-side. Spokes do all the work of spreading around the load as the rim is loaded, deflected upward detensioning the spokes and then picking up the tension as the rim is unloaded. And the spokes do all of the work of driving the wheel forward or stopping the wheel as the hub goes around and pulls the spokes in the respective direction. Rims get all the glory but spokes do all the work.
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