Re: [CR]Another "odd" lightweight frame design.......

(Example: Events:Eroica)

From: "Hugh Thornton" <hughwthornton@hotmail.com>
To: classicrendezvous@bikelist.org
Subject: Re: [CR]Another "odd" lightweight frame design.......
Date: Sun, 11 Aug 2002 04:12:11 -0400


Ouch! I would never suggest that membership of the V-CC is compulsory for anyone interested in classic bikes and cycling history. Any contribution to their funds via membership is strictly for the benefit of the members. I find the publications alone worth more than the subscription, but that is only my opinion that I would not force on anyone else.

With regard to the technical issues of these additional stays, they were not originally added to cope with braking stresses because they were fitted to track and fixed-wheel bikes. Someone might subsequently have thought that they were of benefit in handling braking loads on a touring machine, but it would not be sensible to put them on a racing or lightweight bike for that purpose because the majority of the braking load would be on the front.

The 1930's saw a number of different additional strut configurations aimed at improving the stiffness and therefore efficiency of the bicycle. The fact that they have all died out is testament to their ineffectiveness.

I do not doubt that these stays were an attempt to increase rear triangle stiffness, at the same time as providing some product differentiation in the marketplace. By stiffening the rear triangle, one would hope to reduce the lateral movement of the dropouts relative to the main triangle (the rear triangle is already very stiff in every other direction**). It is fairly plain that these additional struts do not provide a lot of lateral stiffness, and they are so far from the dropouts that their effectiveness is further reduced. This is my basis for thinking that they have no merit, except perhaps on a heavily laden touring machine, other than as a marketing tool.

**Hetchins' curly stays do reduce the stiffness of the rear triangle in every other direction and they are not noticeably slower than other bikes, so perhaps stiffness is not such a big deal.

Hugh Thornton Nantwich, England
>From: Bob Reid <bob.reid1@virgin.net>
>To: <classicrendezvous@bikelist.org>
>Subject: Re: [CR]Another "odd" lightweight frame design.......
>Date: Sun, 11 Aug 2002 00:30:07 +0100
>
>Hugh Thornton wrote,
>
> > I would venture to suggest that these stays are
> > totally pointless except for some possible value as a marketing gimmick.
> > The extra weight will enable you to go imperceptibly faster downhill to
> > partially compensate you for the effort of carrying them uphill in the
>first
> > place.
>
>Without VCC membership, I'm keen to understand what this assumption is
>based
>on ? or is contribution to the VCC's funds a compulsory with membership of
>the list, and a pre-requisite for an informed answer ?
>
>David Rattray's were never ones for frivolous additions and there must have
>been some thought / logic behind their use wether real or perceived. The
>company had no need to use gimmicks to sell machines nor any real
>advertising for that matter at any time over 60+ years of production, but
>were obviously not immune to providing these "customer" specified oddities.
>As to the additional weight ? it's entirely negligible given that we are
>talking about two 3 inch length of hollow tube here.
>
>So what was the point of the similar stays on the Southall machine ?
>
>Bob Reid
>Stonehaven
>Scotland
>
>
>
>
>
>
> >
> > Hugh Thornton
> > Nantwich, England
> >
> >> From: Bob Reid <bob.reid1@virgin.net>
> >> To: <classicrendezvous@bikelist.org>
> >> Subject: [CR]Another "odd" lightweight frame design.......
> >> Date: Sat, 10 Aug 2002 19:31:40 +0100
> >>
> >> But this time it's Scottish !
> >>
> >> As much input as possible (theory or fact) would be appreciated on this
> >> frame ;
> >>
> >> http://www.flying-scot.co.uk/page62.html
> >>
> >> Though dating from 1949, at first It doesn't look particularly unusual,
> >> until you notice it has two more tubes than usual !.
> >>
> >> Is this just another "funny" frame with peculiar ideas ?. Something
>makes
> >> me think I've seen this treatment of the seat stays done before, but
>about
> >> the only benefit I can see from doing it, is to stiffen the ultrathin
> >> pencil
> >> seat stays in reaction to the forces under hard braking.....but I'm
>sure
> >> one
> >> of the framebuilders on the list will tell me different !
> >>
> >> Bob Reid
> >> Stonehaven
> >> Scotland