Originally Posted by CyclesMakaron

It's true... but not exactly one by one: mod options were limited to what was shown and described in catalogues, there was no full freedom as to the model of tubes used and geometry. If you ordered a Corsa model in 1990, you decided on "braze-ons trifles". (number hanger, cable slides, bottleholder mounts etc), you had a choice of Columbus SL/SP or Reynolds 531, but only "road race" geometry. The Corsa Extra model (1990) allowed an amazing choice of options, apart from "trinkets" as many as 4 tube models (Reynolds 753, Columbus SLX/SPX, TSX and MAX), but very strongly related types of geometry (753 - only "road race", Max - only "century", the rest could be ordered in both versions). It should be remembered that the "braze-ons details" models changed over time, they also changed their position (e.g. top tube slides); "chrome plating" was an option, but not in the case of the early 753 (without this option), on the other hand, the fastest way to identify "from afar" the frames of the Corsa 01 and Strada OS is unique for each model "chrome plating", which is just... ceased to be an option; if you add to this seasonal changes in painting patterns and used decals you get the opportunity to organize this whole crazy thing into a logical evolutionary sequence... Fortunately these are only auxiliary elements - the most important are manufacturer's markings placed on BB cover and steering tube (that's why every description of EMC frame should contain these markings - preferably as photos) - their reading solves 90% of problems with EMC frame identification (if you add 3-4 photos of the most important details, clear pictures of painting pattern and decals used - chances increase to 99%).

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