FW: [CR]Vintage Racebike Geometry

(Example: Events:Cirque du Cyclisme:2004)

From: "Ken Freeeman" <freesound@comcast.net>
To: <classicrendezvous@bikelist.org>
Subject: FW: [CR]Vintage Racebike Geometry
Date: Mon, 7 Feb 2005 22:54:26 -0500
Thread-Index: AcUNT4Eid+y+Je81RNinfRw69S3+XAAQGiPgAAB1BhA=

So in the interest of reducing the variables, which I as (guess what?) another engineer applaud, maybe we should write down the targets for the measurement. How much precision? Are all tubes c-c except the seat tube? Will Masis be measured c-t or center to lug point? Will chainstays be measured along the tube or from bb to rear axle along the frame plane-of-symmetry? What should be the position of the dropout adjuster screws?...ad nauseum.

But the point is, if we want people to do the measurement, and if some degree of accuracy is desired, and if we hope the measurements can be correlated and compared afterwards, the key points should be written down so one can find them in the archives.

Chuck, I write standards as part of my living. I'm willing to as a starting point write up neatly (at least for an engineer) what you think as a first draft for a Vintage Bike Geometry Measurement Standard. Then you can all shoot at it, then I write a second draft.

Whadd'ya think?

Ken Freeman Ann Arbor, MI

-----Original Message----- From: classicrendezvous-bounces@bikelist.org [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of BobHoveyGa@aol.com Sent: Monday, February 07, 2005 2:59 PM To: classicrendezvous@bikelist.org Subject: Re: [CR]Vintage Racebike Geometry

In a message dated 2/7/05 2:16:39 PM, classicrendezvous-request@bikelist.org writes:

> Steven Maasland wrote:
> >
> > Chuck,
> >
> > I believe that what you have proposed is indeed a valuable service
> > to all
> of
> us. However, as I do not have any of the measuring tools that you
> mentioned in your post, I am not able to supply any data from my
> bikes. I would nonetheless be grateful if you or any other competent
> person with the proper tools were to take note of the measurements at
> le cirque. I believe many other willing contributors are in the same
> situation as me.
> To which Chuck added:
> The measuring tools can be as simple as string, two wooden yard
> sticks, a $2.00 plastic protractor and a metric measuring tape.
> Not gonna take up my cirque party time measuring bikes for people...
> that's fur sure!
> Anyway, the response has been nil... actions speak louder than words
> on the CR list.
> Chuck Schmidt
> South Pasadena, Southern California
> e-Chuck:
> (With my Engineer's hat on) I think the problem is that measurements
> made by many different people with varying measurement tools and skill
> levels, and likely using many different measurement protocols, may
> yield pretty dubious data in some areas of measurement (e.g. frame angles).
> Steven's idea, while creating more work for the measurer, would yield
> much more reliable and consistent data, IMHO....
> Greg "reduce those variables" Parker
> Dexter, Michigan

Excellent point, Greg. We are talking precision here and you can be dead sure that not everyone's gonna measure using the same standards.

Ken Toda has kindly operated bike photo concession at Cirque the last couple of years, maybe in a similar vein someone could run a bike measuring concession... somebody with a good eye who wants a few extra bucks to cover travel could set up a little booth and charge five bucks a pop to 'blueprint' your bike.

Bob Hovey
Columbus, GA