EMC built steel frames for sure until March 2006 (this is the limited series of 100 Corsa Extra frames in 7-Eleven colours). A report on YT - merckx.m4v - mentions that steel frames account for 5-10% of production (the video is probably from 2002), which means 250-450 frames per year. The frames you showed were painted in EMC, without knowing the serial numbers, it is impossible to determine whether this is the original painting.
EMC built steel frames for sure until March 2006 (this is the limited series of 100 Corsa Extra frames in 7-Eleven colours). A report on YT - merckx.m4v - mentions that steel frames account for 5-10% of production (the video is probably from 2002), which means 250-450 frames per year. The frames you showed were painted in EMC, without knowing the serial numbers, it is impossible to determine whether this is the original painting.
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