Re: [CR] Big frames ride better?

(Example: Racing:Beryl Burton)

In-Reply-To: <4D40D090.6090908@os2.dhs.org>
References: <002f01cbbc91$a1ed14a0$e5c73de0$@com> <4D3F0388.5030101@aol.com>
Date: Wed, 26 Jan 2011 19:39:15 -0800
From: "Jim Merz" <jameshmerz@gmail.com>
To: john@os2.dhs.org
Cc: classicrendezvous@bikelist.org
Subject: Re: [CR] Big frames ride better?


Here is a funny UCI satire of current frame design requirements.

http://goo.gl/JTPgC

Jim Merz Big Sur CA

On Wed, Jan 26, 2011 at 5:55 PM, John Thompson <johndthompson@gmail.com>wrote:
> On 01/25/2011 11:08 AM, verktyg wrote:
> > I can't speak for all makes of bikes or those built after the late 70s
> > but there was a tendency for European production models to all use the
> > same wheelbase length within a brand.
> >
> > This resulted in the smallest frames having a steep seat tube and
> > relaxed head tube which produced bikes that handled like a wheelbarrow.
> >
> > At the other extreme, the largest frame usually had the opposite, a
> > relaxed seat tube angle and a steep head tube. This resulted in the
> > riders weight being concentrated over the rear axle (with the seat up
> > high) and either sluggish or twitchy handling if the fork rake wasn't
> > adjusted to fit the frame size.
>
> Another factor that may have contributed is the UCI regulations on
> "front center" (the distance between the center of the BB shell and the
> center of the front dropout).
>
> We (Trek, that is) sponsored the US Women's National Team back in
> 1983-84, and built bikes for the team to use in competition. Among them
> were a number of track bikes used in the Nationals. These were designed
> and sized appropriately for the riders, some of whom were quite small
> (46-48cm frames). When the team took these bikes to the Worlds, UCI
> objected because the "front center" on the smaller frames was too short,
> so we had to scramble and build several new frames for the worlds (we
> had about a week's notice). IIRC, we had to use ~55cm top tubes on 48cm
> frames to satisfy UCI.
>
> Perhaps now the regulations have been modified to take into account
> frame size and rider size. I hope so, at least.
>
> --
>
> -John Thompson (john@os2.dhs.org)
> Appleton WI USA