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Hello bldec and welcome to the forum!
thank you for sharing this cycle with the assembled
appears to be a contract build performed by Chiorda
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frame -
constructed with Agrati bits
the bulge-formed head is pattern "AM" and is item nr. 000.8046
the bottom bracket shell is "SPORT" pattern and is item nr. 005.8057
fork crown is "SPORT" pattern and is item nr. 026.8058
fork crown cap is Agrati item nr. 202.9110
dropouts are Agrati item nr. 000.8002
fork ends are Agrati item nr. 000.8010
both of the frame's plate style bridges are Agrati pieces
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fittings -
everything looks original save for the rear mech
original would have been Simplex Prestige model 637
headset is Agrati model 000.3071 in economy zinc finish
also offered in chrome finish
stem and bar set is 3TTT Touriste
brakeset is Universal model Sport
Thompson pattern chainset is an Agrati item
this image gives the bearings arrangement on a Thompson pattern bottom bracket assembly, although it shows a cottered version rather than the one on your machine where the spindle is permanently affixed to the right crank arm
pedals are absent in images provided
they likely would have been Sheffield model 663
wheel rims are probable to be Maccari 36 hole in size 27 X 1 1/4"
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your dating is spot on
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there have been several different & unrelated Mondial marques through the years
there is also a Mondiale marque
this outstanding post from member
MauriceMoss gives a thorough exposition on them -
https://www.bikeforums.net/21857047-post3.html
hope you enjoy this machine
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