Re: [CR]Re: Frame Flex

(Example: Framebuilders:Dario Pegoretti)

Date: Thu, 29 Sep 2005 12:18:29 -0700
From: "Kurt Sperry" <>
To: John Clay <>
Subject: Re: [CR]Re: Frame Flex
In-Reply-To: <>
References: <>
cc: Classic Rendezvous <>

Agreed. The best short take on the subject I've seen, seems based on sound first principles rather than anecdotes and unsupported assumptions. Worth the short time it takes to read. Kurt Sperry Bellingham WA

On 9/29/05, John Clay <> wrote:
> One of the things I learned in mechanical engineering school was that
> structural analysis and testing aren't easy and the (correct) results are
> frequently counter-intuitive. Adding an analysis of power delivery as it
> relates to bicycle speed or efficiency and you've got a mighty imposing t ask
> on your hands. Here is an article by an engineer who's put substantial
> thought and effort into modeling a bicycle frame as it relates to power a nd
> deflection. A quick read and his conclusions sound well grounded to me. H e
> doesn't violate any big ticket "first principles" that I can see. The
> analysis and conclusions make sense so I tend to think he's in the correc t
> zip code.
> Short version: I wouldn't be too quick to utterly dismiss reasonable fram e
> flex as an aid to propulsion.