I think Norris is probably spot on with his dating although I have seen Butlers similar to this with the Bastide type double plate fork crown, detachable CB clamp and Chater ends as late as 51. The Butler frame numbering system would be able to date it accurately. Claud Butler built many special frames to order and this could have been a bespoke made job to the owners wants. Hence the variationions from the catalogued Avant Coureur.
Best wishes and be lucky. Michael Butler Huntingdon UK.
>From: "Norris Lockley" <Norris.Lockley@btopenworld.com>
>To: <classicrendezvous@bikelist.org>
>Subject: [CR]Mystery bike du'jour on Ebay.. confirmed
>Date: Mon, 9 Feb 2004 00:37:17 -0000
>
>I thought hat it would be prudent to try to heal the north v south divide
>in the UK by agreeing with Mike that the mystery frame on UK Ebay certainly
>has all the hallmarks of a Claud Butler "Avant Coureur"
>
>As far as can be seen from the pictures it is a fully lugged model and not
>a bi-laminated example which had no "lug" down the seat-tube. Judging by
>the Chater Lea rear drop-outs it is probably no later than the late 40s
>very early 50s. I could be wrong though because I have a Claud B track
>frame complete with cast lugs cut to a very similar but not identical
>design, D-section forks though which dates from an earlier period.
>
>Over to Hilary?
>
>Norris Lockley.. with an after thought..
>
>Why use a seat-lug and not have a seat-bolt eye.. and why use the Italian
>collar type clamping?