Classic & Vintage - Columbus "Inexternal" tubing??

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evwxxx
12-30-06, 08:43 PM
Hi guys - Picked up this Motobecane at Thrift shop couple days ago. It is badged as a Jubilee Sport. According to the decals on the bike, it is built of Columbus "Inexternal" tubing. Has anyone heard of this stuff before? As you can see in the supplied link to a pic of the bike, it is not a lugged frame in the traditional sense, looking more like cheap dept. store construction! Other than that, the bike is all french, with the usual componentry (Nervar, Phillipe, Wolber, etc). None-french parts include Suntour ArX deraillers, Suntour Accushift shifters, and what I believe are Motobecane branded Modolo brakes. Also has internal cable routing thru the toptube for rear brake. Although the frame tubing looks very thin at the opening of the seat tube, it takes a 26.2 seatpost, if not smaller! The original seat tube does not have a size designation on it. The bike is fairly light for a 61cm frame. If anyone knows the background on this model, such as dates of manufacture, what the heck Columbus "Inexternal" etc, it would be appreciated! Thanks for any help. Ed

http://i127.photobucket.com/albums/p134/evwxxx/Picture297.jpg


Max Busch
01-03-07, 03:06 AM
To my understanding, the term "inexternal" refers to the manufacturing process (iirc inner lugs) and not to the tubing. My early 90's MBK was labelled as Columbus Chromor inexternal process.

evwxxx
01-04-07, 02:34 PM
Thanks, that makes sense. "Inexternal" then actually refers to the "non - external" (or inside tubes) way the tubes were joined, and not the material they were made from. ew