Recommended Wheelsets? - Page 3

You're supposed to put the glue on the inside rim of the tubular tires, not the outside. This might explain the glue absorbing a constant amount of energy...

You are kidding, right?
I am talking about rim glue that holds the tire to the rim.
In the case of the poster who is touting the wonders of tubular tires, rim tape that holds the tire to the rim.

Both have a constant amount of energy loss that is significant when compared to the overall losses of tire's rolling resistance.

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David Ornee, Western Springs, IL USA

I don't suppose you have ever researched this so I will take it easy on you and just say..nuh-uh.

Any body else want to carry the torch for a bit?

Nope JohnO he is right on this one. With the tubular glue the tire tends to squirm on the rim just a little. It does increase rolling resistance... that doesn't mean that tubulars ALWAYS have more rolling resistance than a clincher of course, but that it is a factor you can only eliminate with the permanant glue. So a top end clincher will actually have less rolling resistance than a tubular with the same casing.

Not this wheel inertia nonsense again.

What kind of steroids are these guys using that they can spin their wheels so hard that wheel inertia is significant?

Somebody better go tell Chris Hoy to stop using heavy disk wheels on his track bike cuz they are slowing down his acceleration.

No he was talking about climbing which is even more of a half-baked marketing created ideology of "summing all the small accelerations". At least in sprinting there are actual accelerations resulting in measurable changes in rotational speed (albeit small).

Unfortunately, it will probably take 2K - 3K miles before I'll have any kind of definitive opinion on them. I'm sure they'll look fine out of the box but the real test is how they hold up over time. And by then I'll probably forget to reply.


I feel so inadequate with all of these posters talking about these carbon fiber bladed tubular aero wheelsets. I'm just going to go sulk for a while.

You should be smug with your higher bank account balance instead.

Actually, thanks to the corporations outsourcing tech sector jobs to ultra low wage countries, it's more like less charge card debt than higher bank balance. We'll all be flipping burgers before it's over.

Oh that's right, I forgot about all that high G acceleration that occurs when I'm climbing.

Let's see if I add up 1000 tiny .000001 G accelerations how much energy would I save if I were to shave 50 grams off my rim (but added it back to my frame)

I'm guessing if I got a 5 mph headwind for even a split second it would cancel out all the enegy I saved.

Hey wilmar13, thanks for the comments. I'm always eager to learn, so please offer your opinions. 2 quick questions:
1) What is the ideal weight and/or weight distribution of a climbing wheel, and why?
If by chance that is not a valid question:
2) Does weight and/or weight distribution of a climbing wheel make absolutely no practical difference, and why?
Thanks,
Nojiri

I don't know what the ideal weight distribution of a wheel is as there are many parameters you will want to optimize first. The problem is that the whole claim of reducing rotational weight making a difference is dependent on actually being able to accelerate the wheel (in terms of radial acceleration) which you just can't do on a bicycle (most of the little power you can create is sapped by either air resistance or fighting gravity). It makes such a tiny, IMO negligible, difference even in competition that it can be forgotten about. Weight does matter, just not where it happens to fall on the wheel all other things being equal (again, inertia technically matters but it makes almost no difference).

Check out these resources for a much better overview than I could ever provide:
http://www.biketechreview.com/archive/wheel_theory.htm
http://www.analyticcycling.com/WheelsConcept_Page.html (and play with the tools under various scenarios to get a better idea of the effects of all the variables)

And more money for beer.

I go by what experience tells me. Personal experience has been that good tubies, say Conti Sprinters, pumped up to 150psi, seem to roll easier than the typical lightweight clincher pumped up to 80-90. Are we talking theoretical, or real world circumstances?

I see two things you are implying (or rather I am interpreting ) that I would want to slightly disagree with. First, higher pressure is better for rolling resistance, this is only true on a perfect surface, and unless you ride on an indoor track you deal with road imperfections which makes a lower pressure of say 110-120 actually faster (I used to ride on 20's pumped up to 160 and was convinced by all the road imperfections I felt that they were much faster...doh! ). The second is that when comparing tubulars to clinchers you need to compare tires with a similar casing. I totally agree with you that a Conti Sprinter at 150PSI will be a faster, better tire, with more grip, less rolling resistance, better ride, etc. than a mediocre clincher. But if you compare a high end clincher with a supple casing the advantage goes away. About the only real advantage a tubular has over a clincher anymore is weight savings (especially with Zipp rims), but the disadvantages never went away (the losses from tufo tape are worse than glue). I have a set of tubular race wheels but a set of Vitoria Evo CX clinchers ride just as well on my trainers. And yes I am talking about real world here. Many Pros even race on clinchers and they don't have to deal with any of the disadvantages those of us without mechanics deal with. Here is a link, I am sure others can post more about the PSI issue:

http://www.sheldonbrown.com/brandt/r...e-tubular.html