Any of you BB experts know how to date these things? I have a Japanese 3000S, and a Taiwanese 1100S, and I just wondered if anyone knew how to nail down a date of manufacture for them? Yamaha won't reply to email. I know they're both 1980s, I guess the 1100S is a little later than the 3000S, but I'd like to find out exactly if possible. Also does anyone have an original '80s BB catalogue they want to sell? Thanks.