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Made in Taiwan.
Fourth digit in the serial indicates year of production (2001 or 2002). X in the example above indicates production Month (E to L - May to Dec) . Y in the example above indicates production Month (A to E - Jan to May). 21 in the example above indicates TR2.1.
Bikes made in Taiwan usually had an 6-8 month production and shipping timeline before they were sold in bike shops around the world. Around April/May of any year, factories would usually switch production to making models for the following year.