Originally Posted by A.Winthrop

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Hi T-Mar,
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Very interesting. The apparent 1980 or thereabouts switch
seems to conicide with the disappearence of the Professional
and, later, the Semi-Professional models (ie the Cinelliesqe
knock off models). I wonder if there is a connection?
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There must be cyclists and others in Japan who know what
manufacturer made what brands. All must have been made
within the manufacturing sphere of one of the big Japanese
manufacturion\trading combines and that Japanese industrial
structure should make it easy to trace manufacturing if one
is Japanese or is literate in Japanese and can probe
Japanese websites.
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I've got a Japanese friend, a former journalist, who is now
spokesman for the Japanese Foreign Ministry. I'll see if I
can enlist his help. He was a political AND business journalist
for Asahi Shimbun, a major Japanese newspaper with both Japanese
and English-language editions, so maybe he can point me to
someone who would know.
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If memory serves, you once speculated that the N in the '80s
Centurion serial numbers might stand for National. I'll bet
you are correct. I think it was you who pointed out that
National also manufactured Panaracer tires, which appeared
on many mid- and late-80s Centurions. This theory may be
a good starting point for investigation.
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Oh, almost forgot to ask: Do you now have enough evidence
to support a dating code theory on the M-series serial
numbers? And, if so, does it conform to the N-series dating
code?
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