[CR]Seat stay design: varying seat tube connection pt.

(Example: Component Manufacturers)

Date: Sat, 29 Jul 2006 09:40:58 -0400
From: <oroboyz@aol.com>
References: <18177-44CB018B-1584@storefull-3272.bay.webtv.net>
In-Reply-To: <18177-44CB018B-1584@storefull-3272.bay.webtv.net>
To: classicrendezvous@bikelist.org
Subject: [CR]Seat stay design: varying seat tube connection pt.

Illustrating the extremes of what you guys are talking about: this steel prototype frame was shown at the Interbike show in 2001...

http://www.cyclesdeoro.com/images/Interbike%20Shows/InterBike01/Grail_1.j pg

Dale Brown Greensboro, NC USA

-----Original Message----- From: theonetrueBob@webtv.net To: classicrendezvous@bikelist.org Sent: Sat, 29 Jul 2006 2:34 AM Subject: [CR] Seat Stays: dynamic effect of varying seat tube connection pt.

Hi Don,

Interesting question! Now, if we're bracing stays across the seat tube to anchor along the top tube, would the "Mixte" concept also count?

And, what exactly would we looking for in terms of an "excellent riding bicycle"?

Personally, I tend to view modern CF "compact" road racing frames as mutations - with just a lowered top tube and a truncated seat tube... and then an absurdly long seatpost is shoved out the top like a circus bike. Today, even a typical Cannondale is also commonly made with a greatly extended seat tube protruding way beyond the level of the top tube, and they are even measured to the top of that extension.

How do these fit into the whole scheme

Couldn't you say that an actual mounting point of a seat stay should really be considered "lowered" on some bikes - if you consider some imaginary "virtual" top tube horizontal line based on... perhaps the head tube height?

Cheers!

Bob fist-full-of-post Hanson, Happily straddling my too-tall bikes, in Albuquerque, New Mexico, USA

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Don Wilson wrote:

Frame builders have connected seat stays to the side of the seat cluster, to the underside of the binder bolt mount in the seat cluster, to the back of the binder bolt where the seat cluster is, and Hetchins among others have routed the seat stays several inches down the seat tube and extending to connect with the top tube several inches ahead of the seat cluster. What is the dynamic effect of moving the seat stay connection point up or down the seat tube (other things being equal)?

How far down a seat tube could the seat stay contact point be lowered and still result in an excellent riding bicycle?

Don Wilson
Los Olivos, CA USA