Classic & Vintage - spotting Columbus SL

I just purchased a frame off ebay and it was advertised as columbus sl tubing.. There is no stickers on the bike so i was wondering if there is any i should be looking for to identify this frame. There are numbers stamped on the bottom bracket they are 493 22... and the drop outs are columbus as well.. there is also a cable guide on the bb that is stamped with modele vitus depose..

Thanks

Usually there is a Columbus Dove logo stamped on the fork steerer tube and I think I heard that the SL and SLX both had the rib reinforcements inside the lower end of the steerer tube as well. Problem with both my things to check is it only proves the fork is Columbus tubing.

Usually there is a Columbus Dove logo stamped on the fork steerer tube and I think I heard that the SL and SLX both had the rib reinforcements inside the lower end of the steerer tube as well. Problem with both my things to check is it only proves the fork is Columbus tubing.
True and true, but the clues are helpful in that most bikes with stock Columbus SL (or SP, SLX, TSX whathaveyou) steering columns will also have been built with the whole corresponding Columbus tubeset. Consider: if you were going to scrimp anywhere to save a buck, you'd braze in a plain guage steel steerer cause the customer will almost never see it. Likewise the use of quality forged dropouts (whether Campy, Gipiemme, or stamped with Bianchi or the Col. Dove) *usually* indicates that quality tubing was used, but another clue would be the size of the seatpost: 27.2 in an Italian frame is a good pointer toward it being at least some sort of DB lightweight crom-moly steel. Sounds like your BB cable guide is French, but I take it that's a bolt-on plastic piece and if so it doesn't indicate much about the country of origin, but might help ID the maker...pictures always help!

Unfortunately stickers don't always mean much, either. I bought a "Columbus SL" frame (old 80's style decal) off ebay that even had a Columbus fork decal on what turned out to be a Tange fork. What was even odder was that after I stripped the paint I could faintly read the Reynolds DB 531 engraving in the main frame tubing. Someone had re-decaled a 531 frame as SL :rolleyes: Only in the 80's

SL /SLX - Just a quick note: I was once told, by a well respected frame builder / bike shop owner / top rider that it was possible to stick a finger up the down tube via the bottom bracket and feel for the rifling of the SLX tubing. I've never tried this and I think the pinning process prior to brazing may prevent this happening on some frames.

the bike is an 1988 rocky mountain giro,the steel seems super thin and light so i think it is a high grade! the fork drop outs are both columbus and one rear drop out is columbus and the other is campy..The seller said he assumes the derailer side was broken and replaced at some point in the bikes life.