Interesting thread. I just ended up with twin Nishiki 10-speeds, so I'll post the preliminary info here for the database, then will add some pics and additional details over the next week or so as I find the time. We're down to close to the Dec. 1st deadline of no more overnight street parking winter rules coming into effect, so I"m in the process of turning the garage back into a garage instead of my home motorcycle and bicycle shop.

Anyway, both bikes are (edit: make that blue, not red), both are Nishiki Sport Series with a model name of "Century" on the top tube. Both have G0986 on one rear dropout, on their other rear dropout one has 6461754 and the other has 6463127. Both are close to a 49cm sized frame. There is a sticker that says 1207, and either on the same or a different sticker it has Tensle Steel. (My initial notes are a little unclear with my random scribbling on a piece of paper I had in my pocket, I will clarify things when I get some spare daylight time.)

I'll have to get back to you on the rim material and tire sizes and possibly some dates on the components if I can figure out that aspect. Not sure what I'm going to do with them yet, might do a flip, or maybe keep one stock and singlespeed the other one (one has a few issues more than the other one), or maybe I'll just hang them both in the rafters until next summer and decide then. In any case, now that I know about this thread, I'll post a followup and some pics once I get back to the bikes and can get some accurate details.