The virtues of Sekai bikes were recently touted on the iBob list by Don Gillies: http://search.bikelist.org/getmsg.as...10610.1854.eml. Don owns a 4000, so you might want to contact him for specs (he might have catalogs, too).

My wife is the original owner of a Sekai 2400, her high school graduation present. It's a fine, servicable bike, a bit nicer than many of that era w/ serviceable Japanese components throughout.

Neal