On Jan 15, 2011, at 6:05 PM, Thomas Dockery <driveadime@msn.com> wrote:
> I worked for the mid west distributor for Sekai between 1981 and 1984 (Champaign Cycles, Champaign Illinois). The 4000 and 5000 could be bought as a complete bike or frameset. The 4000 was a touring design built with Tange #2 Cro-Mo tubing. The 5000 was a racing design with Tange #1. Both of these bikes where very nice builds for mass-manufactured frames. There where built by a company in Japan which did several labels including Sekai. I am sorry, I dont remember the name of the company. Peter Davis at Champaign Cycles could give you the real details. I beleive he is still involved in the business.
Check out Yellow Jersey's Sekai page, where there is a link to a 1975 catalog:
http://www.yellowjersey.org/
According to the 1975 catalog, in that year the "Criterium" 4000 had Tange #1 tubing and the "Superlite" 5000 had the .6mm/.3mm superlight Tange tubing. I think the 4000 model evolved a bit over the years.
There is a review of the 4000 from 1974 here:
http://www.velo-pages.com/
If I may hazard a guess, Brian's bike would have a serial number that starts with "M" followed by the last digit of the year of manufacture.
James Black
Los Angeles, CA