I was about to say it looks like something that Schwinn might have ordered then I saw Alex's picture of a Sports Tourer with that on it. Here is a web site that shows all the TA stuff:
http://www.blackbirdsf.org/
The guard would have also been used in pairs for cyclocross, one on either side of a 46 or so ring.
Message: 4
Date: Fri, 21 Jan 2011 11:10:24 -0500
From: <aruland1@tx.rr.com>
Subject: [CR] Curious about this part
To: classicrendezvous@bikelist.org
Message-ID: <20110121161024.5GGS2.253433.root@cdptpa-web23-z01>
Content-Type: text/plain; charset=utf-8
The part is a TA Pro 5 Vis ( cyclo-touriste) chain ring set (54,40) with an
outer chain guard and another alloy ring between the toothed chain rings.
Pictures: http://www.flickr.com/
I have used TA cranks in the past but have never seen this configuration nor can
I find any reference to it at several sites. Perhaps someone in the group can
shed some light. Thanks Andy Ruland
Bob Freeman Elliott Bay Bicycles 2116 Western Ave Seattle, WA 98121 206-441-8144 http://www.elliottbaybicycles.com http://www.davidsonbicycles.com
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