I guess It is early Colnago. Is it Colnago? I don't know whether the original?

Yes... maybe mid to late 70's.

Can you post a picture of the brake bridge and rear dropouts (from the gear side)?

I don't think the fork is. It looks like one of the bikes that gets resprayed Colnago again and again.

I am not confident the frame is but not sure that it is not.
Seat stays are non standard, the BB shell is later but at the time this style of shell piercing was used only the lower head lug a clover.
I am not sure the BB shell is cast from the looks of the sockets...

Strange. Maybe a repaint with braze-ons added?

Looks like a '72-'73 that had shifter and top tube guides brazed on? But, I've never seen that circle on the fork crown before...

Took a while to remember, I think the fork is a Cornelo.

Touchdown.

Aha!

Clover in BB doesn't look right, even for a later model. The one below is genuine and there are subtle differences:



No Colnago would have cutouts in the top head lug and seat lug after 1972. I think someone modded the typical Cornello cutouts to give them the correct, triangular shaped stems and then repainted. The cutouts probably looked similar the the one in the fork crown.

There's just too much iffy going on here - I'd pass. There are plenty of Colnagos out there - ones that are genuine and not hard to prove they are so.

DD

Memorex.

The seat stay caps don't look like the fluted ones on every Colnago I've seen.

Trying to learn the subtleties of Colnago's. The seat stays look overly large to me. Any validity in that observation?

I'm having deja vu with this bike frame!
I remember someone else asking about a similar frame (or this one), maybe on this forum or elsewhere.

Same here. I think there were several even. Here's one I found: https://www.bikeforums.net/showthread...ed-Koga-Miyata

Colnago used for almost two decades double taper seat stays. In looking at the BB chainstay sockets, the stay ends at the dropouts, the lack of any reinforcement at the chain stay bridge, this is not a Coplnago.
The seat stay top cap treatment and cutout under the top tube on the seat lug point to Cornelo.
DD also made a nice visual comparison of the BB cutout, I think this frame got modified before it got repainted.

Wish I had my Mexico to compare. Sort of thinking along with DD but its a tough call. I have seen those stay caps but the stay bridges bother me. The bb clover might be the key. The pic below has the OP in question and the legit from that gold color frame above. Check out the bottom two. Not the most precise.

I can add redundancy! 1983 Superissimo:

The bottom cut-out in the seat tube lug is wrong, as well as that bb cut-out. Very suspect. May be a great bike, but not worth any more than any other comparable build. The Colnago name and prestige unfairly adds financial value to a bike. Don't pay that premium if you can't get your money out of it at a later date...

Is this an Ebay purchase?
I'm going to guess it's a Dutch frame that has been made to look like a Colnago.

Yes I bought this item.

I recently bought a Gazelle that was repainted as a Colnago.

Mine is scheduled for a refinish.

What are your plans for this interesting bicycle?

IMO big chance the frame and fork are dutch. Colner or something like that?

Some more points of reference from mine, as received from original owner, date ~1981

Head lugs, Seatstay, brake bridge, and chainstay→dropout interface all appear different. Year of manufacture will make some difference of course.

I make fixie this frame. So, I don't much care

in addition to EVERYthing else that's not correct...it has 3 top tube cable guides...kind of a big obvious.
I also vote this is a Cornelo or some similar Benelux brand. May be a fine rider and since you're fixafying it...who cares about pedigree?