Re: [CR]steering geometry

(Example: Framebuilders:Jack Taylor)

From: "Jon M. Schaer" <jschaer@columbus.rr.com>
To: "dave bohm" <davebohm@home.com>, <rocklube@adnc.com>, "Steve Freides" <steve@fridayscomputer.com>
Cc: <classicrendezvous@bikelist.org>
References: <20010521.162610.-266283.11.richardsachs@juno.com> <3B098973.7195835B@fridayscomputer.com> <3B0A1A52.79B5@adnc.com> <003d01c0e2d9$ecba8040$56f90541@tucson1.az.home.com>
Subject: Re: [CR]steering geometry
Date: Tue, 22 May 2001 19:48:42 -0400


----- Original Message -----
> From: dave bohm <davebohm@home.com>
> Surprisingly, or maybe not, some modern bicycles have trail measurements
> that fall below this optimum range of trail measurements. Take a modern
> frame with a 74 degree head tube and a 45mm kestrel fork. The trail on this > setup would be 49.5mm. This is too low in my opinion and this bicycle
> would tend to become unstable at higher speeds.
>
>

I follow and agree with the general theme of the post, but this specific example might be a tad misleading, if you're refering to the Kestrel EMS fork. That fork had a 45mm rake because of the unusually high crown seat height, which raised the front end and slackened the head angle enough that the end result (if you do the math with the revised HA) was pretty close trail-wise to using a normal fork with a 40mm rake. The newer EMS Pro fork has a normal crown seat height and 40mm of rake.

Otherwise, this is an incredible thread. Any other builders going to chime in and reveal a few secrets?

Jon Schaer