Looking for info please

[Jesper]

@Welshphil
Hi Phil, the head tube is the section of the frame that the fork inserts into, and it usually has the bike's logo as a decal, badge plate, or engraving. The bottom bracket is the cross tube that holds the crank spindle and bearings assembly. Usually, the thread specification is indicated on one or both of the exposed ends of the bottom bracket bearing cups where the crank arms attach. Thread types: Italian= 36mm x 24 tpi; French= 35mm x 1mm (25.4 tpi); Swiss= 35mm x 1mm (25.4 tpi); I.S.O. British= 1.37"- 1.375" x 24 tpi. Most bottom bracket shells are 68mm, or 70mm (Italian) in length.
Note if you plan to remove the bottom bracket: Italian and French cups are all righthand threads; I.S.O./Swiss are righthand threads on the left side (non-drive side) cup and lefthand threads on the right side (drive side) to prevent loosening from precession (left side pedals are also lefthand threads). I assume it has I.S.O. or French threads though French threads may have been phased out by the time your frame was made (~mid '80s). I doubt a Belgian builder was using any Italian dimensions although I am sure there are exceptions.

 

[non-fixie]

(...) I doubt a Belgian builder was using any Italian dimensions although I am sure there are exceptions.

One exception I am aware of, and which may be relevant here, is that there were Belgian builders that used 70mm shells with BSA threading. @juvela may know which builders were involved.

 

[Jesper]

I think the Italians would at least get their flag colors in the correct order consistently. Between those 2 frames it seemed like they tried to use nearly every combination there is

The naming is very normal given brands like Cornelo, et al. having an Italian flavor were common n that region during that era. One might get away with using an Italian flag if the actual builder (ex-pat) or tubing was of Italian origin.

Curious if the Swift trademark decal is the parent company. I am not familiar with that region of bike manufacturing unless it is of a bike I personally own.

26.2 seat post is probably decent mid level frame tubing (would assume seamed) if the seat tube is metric/28mm OD; not "gas-pipe" anyways.

 

[Jesper]

One exception I am aware of, and which may be relevant here, is that there were Belgian builders that used 70mm shells with BSA threading. @juvela may know which builders were involved.

I recently picked up an early-mid 80s Cornelo that is all Italian threads (BB & headset); 70mm BB. I assume it must have been from an Italian builder whom the Cornelo marque contracted their frames from.