Originally Posted by
unworthy1
Thanks, at least that answers our question about where we'd seen that pattern before...but the chainstay bridge on every one of those Colnagos is the same but different from the OP's track frame. Based on that I'd say his is not a Colnago (and of course the English threads).
from searching around yesterday, i got the sense that the particular drilling pattern pictured was sort of a generic modification seen on a number of different manufacturer's bikes in the 1970's, and not the logo of a particular brand or builder.