Originally Posted by Drillium Dude

James: a lot of small builders made the actual frames for riders in the peloton, particularly at the Worlds; they may have been branded as one thing or another, but the builder could be different than the name on the downtube. I know in particular that Marinoni built frames that were rebranded. If an unsung builder built and provided, say, the "Colnago" of the winning World Championship rider, the actual builder would be entitled to put the rainbow stripes on subsequent frames produced from his shop.

For a fairly recent example: Caloi was the sponsor of the Motorola Team bikes, thus Caloi (a Brazilian bike manufacturer in their own right) appeared on the downtubes - but as everyone knows, the bikes were actually built by Merckx

DD