Originally Posted by
Kommisar89
That's an interesting frame - I agree with most of what's been said so far except maybe the dating which is problematic based on the components. The first frame has what looks like Valentino derailleurs which would typically date it prior to around 1975 but that Ofmega crank looks like a swaged crank and those were not common until the late 70's so that's kind of odd. The second frame is equipped with what looks like Campagnolo 980 shifters and rear derailler. Those first appeared in catalog 18 in 1984. The old front derailleur looked out of place but lo and behold, Valentino derailleurs still appear in the 1984 catalog so I would date the first one from late 70's to early 80's and the second one to around 1984.
I do not think that is a valid assumption. It would make a lot more sense to me that the rear derailleur and shifters were changed in the 80's.
The crank and front der are correct for a mid 70's low Rekord level Bianchi, and that's what that the blue frame is. The OP states they are identical and were bought at the same time. If so then that is what the repainted frame is as well.
I do not know if the Valentino front der was available in 1984, but if so I can't think of any OEM that would use it on road/sport model, especially in conjunction with a rear der and shifters from a different group. Bianchi certainly did not. Maybe they were being used on "city bikes" or just selling off old stock?