Re: [CR]Rearward opening rear dropouts REDUX

(Example: Framebuilders)

In-Reply-To: <BAY115-F300FFBAB06C307240CFE81BFB30@phx.gbl>
References:
Date: Tue, 9 Jan 2007 11:13:47 -0500
To: "neil foddering" <neilfoddering@hotmail.com>, classicrendezvous@bikelist.org
From: "Sheldon Brown" <CaptBike@sheldonbrown.com>
Subject: Re: [CR]Rearward opening rear dropouts REDUX


Quoth Neil Foddering:
>In October last year, there was some speculation as to the reason
>why bikes, especially track bikes, were built with rearward opening
>rear dropouts, and I believe that this issue wasn't resolved.
>
>I've just bought a 1939 Claud Butler catalogue, which states that
>the purpose of these dropouts is to allow a change of gear ratios
>(i.e., by changing the rear fixed sprocket) without having to alter
>the chain length each time for a larger or smaller sprocket. The
>wheel would simply be located forward or rearward in the dropout to
>adjust the chain tension according to sprocket size.

That's got nothing to do with the rear-opening aspect. Proper horizontal dropouts, such as the classic Campagnolo 1010 also permit this adjustment.

Indeed, real horizontal dropouts generally have the slot angled downward toward the front, which makes this adjustment more convenient when a rear rim brake is fitted, because one doesn't need to re-adjust the height of the brake shoes.

Rear-opening fork ends have no virtue for well designed frames, they're just an atavistic styling exercise.

It is true that for frames with stupidly short chainstays rear-opening fork ends are the way to go.

Sheldon "Turn On, Tune In,..." Brown +-----------------------------------------------------------------+ | Love seems the swiftest, but it is the slowest of all growths. | | No man or woman really knows what perfect love is until they | | have been married a quarter of a century. --Mark Twain | +-----------------------------------------------------------------+ --
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