I'm new to the forums (and to biking) but I've been reading your posts trying to build up my knowledge. I bought a Nishiki Olympic and I'm trying to get more information about it (mainly the date). I tried dating the components but it hasn't worked out...the Shimano rear derailer has this number: L523 VIA and front has 2204 VIA. I looked under the bottom bracket for the serial number and not sure which one it is. I see:
G0886 or G0386 (can't make it out)
Cranks are Sugino VP, Shimano Light Action derailers, 6 speed cassette, SR seat post, Specialized stem, front rim is Araya, rear is a generic replacement, diacompe brakes and levers, headset is Tange Seiki Levin No. NL 500. Thanks everyone!