Re: [CR]1,000 expert opinions are better than one measurement

(Example: Framebuilders:Richard Moon)

Date: Fri, 19 Jul 2002 08:50:13 -0700 (PDT)
From: "Tom Dalton" <tom_s_dalton@yahoo.com>
Subject: Re: [CR]1,000 expert opinions are better than one measurement
To: classicrendezvous@bikelist.org
In-Reply-To: <02a701c22f16$c5810c30$6400a8c0@bourke>


Real world experience has shown me that wheels are not, for any practical purpose, infinitely stiff. I get the intent here, I think. The intent is that "give" in the tire is so much greater than in the wheel (cited here as two orders of magnitude), that wheel-to-wheel differences are irrelevent. This is not my experience, FWIW. I had 32 hole Omega XL clinchers with 20c Highlight Supercomp HDs. They rode nice, almost cushy in the saddle. They were also very delicate and eventually I dented the rear, tried to fix it, and it cracked. Replacemnets were NLA, so I went with a totally different Campy rim, the Omega V-section. I used the same rims, tires, tubes, and rimstrips, and the same model spoke (DT comp 14/15). The new wheels were MUCH harsher feeling at the bar and saddle. I had no expectation that they would be radically different, so I don't think there is any power of suggestion, prejudice or whatever. FWIW, the V's are very durable and stiffer out of the saddle, so I tolerate the vibration. I did grab 3 pair of XLs from Renaissance when BC had some. I'll build em up, just for fun, and compare directly. Tom dalton Bethlehem, PA Stephen Barner <Steve@sburl.com> wrote: Mark,

I have included the relevant phrase from your original message. I shouldn't have used the quotes, as I hadn't gone to the bother of digging up the original post. If I got the intent wrong, I am sorry. I think the majority of experienced riders would say that they have noticed a difference in the ride of different wheelsets that appears to be significantly greater than the differences resulting from tire pressure, tires, and rotating mass.

Can you provide any more information about the lab tests you referenced? Did they measure such factors as the amount of road roughness that is telegraphed through to the hub, or the reaction of the wheel assembly to a major impact? Or did they just measure static deflection under load?

Steve Barner, skeptical in Bolton, Vermont

From: Mark Bulgier To: classicrendezvous@bikelist.org Subject: RE: [CR]Twisted spokes Date: Tue, 16 Jul 2002 18:10:56 -0700

--Snip--
>The claims are especially unrealistic with respect to stiffness, because
>even if the spoking pattern could double the stiffness (an absurd suggestion
>no one is claiming), no one would notice. That's because all wheels are,
>for all practical purposes, infinitely stiff vertically already. Any
>vertical give they have is masked by the give in the tires, which is
>probably a hundred times greater. Vertical stiffness of wheels can be
>measured in the lab, but the differences are beyond the range of human
>perception. By the way, tied-and-soldered was not found to have any effect --Snip--
>Mark Bulgier
>Seattle, Wa
>USA

----- Original Message #2 ----- > From: Mark Bulgier
> To: classicrendezvous@bikelist.org
> Subject: RE: [CR]T&S Spoking
> Date: Thu, 18 Jul 2002 22:00:02 -0700
> --Snip
> Not sure whom you're quoting there but I think it may be me, so I should
> protest, I never said wheels are "infinitely stiff in the vertical plane."
> I even explicitly said the stiffness difference between wheels was
> measurable - therefore obviously finite. The thing you call "ludicrous to
> think", no one here is thinking.
>

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