Re: [CR]Vintage Racebike Geometry(more)

(Example: Framebuilding:Paint)

Date: Sun, 13 Feb 2005 22:01:12 -0800
From: "Chuck Schmidt" <chuckschmidt@earthlink.net>
To: classicrendezvous@bikelist.org
Subject: Re: [CR]Vintage Racebike Geometry(more)
References: <MONKEYFOODfN3vSAMfK000012d0@monkeyfood.nt.phred.org>


Thanks for participating Roman! Using the Steering Geometry Calculator at: http://www.kreuzotter.de/english/elenk.htm I used 68.0cm for the diameter of a typical tubular (sewup) wheel:

Your 1975-77 Pinarello HT angle of 74° & Wheel dia. of 68.0cm & Rake of 5.25cm = Trail of 4.3cm

Your 1989-90 De Rosa HT angle of 75° & Wheel dia. of 68.0cm & Rake of 4.70cm = Trail of 4.2cm

Chuck Schmidt South Pasadena, Southern California

Roman Stankus wrote:
>
> Being interested in frame geometry, I love this topic and have wanted to
> measure my frames, but am just starting to get to it. Only a few to do. My
> lovely wife Amy assisted me in measuring these bikes. Its hard to get spot
> on with the measurements when eyeballing the centerline of the HT/fork to
> get the HT angle, but I think they're very close.
>
> My 75-77? Pinarello - rides great but not as quick a turner as my 80's De
> Rosa's
> ST 58cm
> TT 58cm
> ST angle 73
> HT angle 74
> Rake 52.5mm
> BB drop 77.5mm
> CS 415mm
> Wheelbase 100.25cm
> Trail(calculated myself?) 4cm
>
> My 89-90 De Rosa (KOF for comparison)
> ST 59.5cm
> TT 58cm
> ST angle 74
> HT angle 75
> Rake 47mm
> BB drop 75mm
> CS 415mm
> Wheelbase 101.5cm
> Trail(calculated myself?) 4cm
>
> I'll work on some more later. It would be interesting if bikes displayed at
> Cirque could include this info.
>
> Roman Stankus
> Atlanta, Ga.
>
> -----Original Message-----
> From: classicrendezvous-bounces@bikelist.org
> [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of Chuck Schmidt
> Sent: Monday, January 31, 2005 1:50 AM
> To: classicrendezvous@bikelist.org
> Subject: [CR]Vintage Racebike Geometry
>
> The results so far... here's some of my bikes (anyone else care to
> contribute?)
>
> 1939 Bianchi #718923-0
> (c to c)
> Seat Tube -- 54.0cm
> Top Tube -- 58.0cm
> BB drop -- 8.0cm
> Chain Stay -- 46.0cm
> Wheel base -- 110.0cm
> Seat Tube < -- 71.5°
> Head Tube < -- 70.0°
> Fork Rake -- 8.0cm
> Trail -- 4.0cm*
> *wheel dia. 68.5cm
>
> 1950 Bianchi Folgorissima #287197 (P-R derailleur)
> (c to c)
> Seat Tube -- 57.0cm
> Top Tube -- 57.0cm
> BB drop -- 8.2cm
> Chain Stay -- 45.0cm
> Wheel base -- 104.0cm
> Seat Tube < -- 73.00°
> Head Tube < -- 74.25°
> Fork Rake -- 6.0cm
> Trail -- 3.4cm*
> *wheel dia. 68.5cm
>
> 1960 Cinelli SC #7094
> (c to c)
> Seat Tube -- 55.5cm
> Top Tube -- 56.0cm
> BB drop -- 8.0cm
> Chain Stay -- 42.5cm
> Wheel base -- 102.0cm
> Seat Tube < -- 73.0°
> Head Tube < -- 73.0°
> Fork Rake -- 5.5cm
> Trail -- 4.6cm*
> *wheel dia. 68.0cm
>
> 1963 Masi Special
> (c to c)
> Seat Tube -- 56.0cm
> Top Tube -- 56.0cm
> BB drop -- 8.0cm
> Chain Stay -- 44.0cm
> Wheel base -- 103.0cm
> Seat Tube < -- 73.5°
> Head Tube < -- 73.5°
> Fork Rake -- 5.5cm
> Trail -- 4.3cm*
> *wheel dia. 68.0cm
>
> 1980 Colnago Super
> (c to c)
> Seat Tube -- 55.5cm
> Top Tube -- 55.5cm
> BB drop -- 7.0cm
> Chain Stay -- 41.7cm
> Wheel base -- 100.0cm
> Seat Tube < -- 74.0°
> Head Tube < -- 74.0°
> Fork Rake -- 4.6cm
> Trail -- 4.9cm*
> *wheel dia. 67.5cm
>
> Trail calculation http://www.kreuzotter.de/english/elenk.htm
>
> Chuck Schmidt
> South Pasadena, Southern California
>
> .