himespau 

I'm not able to provide the level of detailed analysis that Gary Fountain had, but as a comparison, here is my bike that's been identified as a 1989 Colnago Super (I think Super Piu as I've been told that all Colnagos of that era that had internal top tube routing of rear brakes like yours and mine do have Piu added to the end of their name).

(saddle has been leveled - and changed - along with a few other positional changes like bars slightly rotated since that picture, which was from an initial shakedown ride)

As you can see mine has the C around the Club on the fork crown that Gary mentions and lacks the "comma" cutout in the head tube lug that yours has.

Mine also appears to be made of Columbus SP tubing due to the size (no helical reinforcements of SLX or SPX but fits a 27.0 seatpost - it would probably prefer a 27.1 as the 27.0 slips a bit even with carbon paste but a 27.2 won't fit).

The differences is our paint schemes may or may not indicate a different year. I think I've seen a similar scheme to yours in 1988 catalogs online (but I could be misremembering the year), but have not seen a 1989 catalog to see if it is in there as well or to verify mine - and I don't remember where that catalog was, so I could be thinking of a different year.

The clover engraving on your seat stay cap is painted white, while mine is black; don't know if that means anything or if that's just the paint scheme differences. I wish mine were white like yours as it would "pop" more.

Mine has what appears to be a moveable race number hanger (2 different threaded holes to screw it in that are maybe an inch or 2 apart with the hanger screwed into one of them), which yours does not, but I haven't seen that on any other Colnago, so I don't know what that means.

Yours has the brake cable entering the internal routing on the bottom and exiting on the top, which I always sort of thought came after the "both top entry" that mine had (once manufacturers started realizing that the top entry was leading to sweat entry and corrosion), but that might also be a model difference or a different contract builder.