Re: [CR]Frame stiffness

(Example: Component Manufacturers:Cinelli)

From: "Charlie Young" <youngc@netreach.net>
To: classicrendezvous@bikelist.org
Subject: Re: [CR]Frame stiffness
Date: Mon, 10 Mar 2003 12:29:49 -0500

I don't know the extent to which the testing apparatus is "real world" but it certainly provides relative stiffness measurements between frames under a controlled set of circumstances. The problem with the "real world" is that you have a host of uncontrolled (and potentially confounding) variables coupled with highly subjective data on the amount of frame flex at the BB.

Indeed, it might be useful to see the shapes of the curves of flex at the BB under different weights. It could be distinctly non-linear. Some frames might deflect a good amount under low loads then stiffen up.

Charlie Young Honeybrook, PA
> I don't want to debate the benefits of
> stiffness, or the idea of measuring only
> the bb stiffness and making conclusions from
> that data, but isn't the method here flawed?
>
> I would think the rider can generate force
> beyond only their body weight?
>
> The conditions shown make it look like the
> flex is only a couple of mm, "so what's all
> the fuss about" could be someone's conculsion.
>
> That doesn't look too "real world" to me:
>
> http://technology.open.ac.uk/materials/bikeframes/bikeframe.html
>
> Grant McLean
> Toronto.Ca
>
> O \O/
> _< \_ _< _
> (_)>(_) (_)>(_)