brycoy - 2010-07-08 4:10 PM also foggy on wheels...what is deeper? i see measurements in ads from 30-70+mm. What do these measurments refer to? when you by tires and tubes for "deep clinchers" are they different? what are disadvantages of going too "deep"? (besides price goes up with depth). what about lifespan of the wheels...is that related? if deeper is always better, why make shallow rims at all?
what is deeper?
"Deep" refers to the material in the wheel between where the tire ends and the center of the wheel. The deepest wheel you can buy is called a disc, which is one solid piece of material with no spokes at all.
when you by tires and tubes for "deep clinchers" are they different?
Generally, no the tires and the tubes would be the same, there is a different kind of wheel called a tubular that has a different system of tubes and tires though, many of your most expensive wheels are tubulars.
what are disadvantages of going too "deep"?
As you stated, price is a concern, Deeper wheels also tend to be a bit heavier which isn't an issue for most triathlons, but lighter wheels are better for steep long climbs, and quick sprint efforts. Lastly, really deep rims have a sail effect while riding, so if you're riding in conditions with stiff crosswinds you do risk getting blown off the bike. For this reason, some races like the Ironman word championships in Kona, HI don't allow disc wheels because the course is so windy.
In general, the advantages of deep section wheels outweigh the disadvantages, so most triathletes who can afford them ride a very deep front wheel, and a disc wheel in the back if they're able.
what about lifespan of the wheels...is that related? if deeper is always better, why make shallow rims at all?
Deeper all carbon wheels aren't nearly as durable as regular aluminum box rims. The carbon wheels are also more difficult to repair if they get knocked out of whack. Because of this, most people train on regular wheels and use the expensive carbon ones only on race day. There are other reasons someone might choose shallow rims where triathlon isn't really concerned, but I don't want to further muddy the water.
And, because a picture can be worth 1000 words: Deep rims, vs shallow ones:
(boxrims.jpg) (corvos_fabian-cancellara.jpg) Attachments
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boxrims.jpg (45KB - 12 downloads)corvos_fabian-cancellara.jpg (37KB - 9 downloads)