^ French 531 was Metric OD (28.0 not 28.6) so plain had ID 26.2, and DB 26.6 (or 26.4).
Unlikely that this is a French frame though, what with it coming from Bolton. Easy way to find out would be to stick vernier around the seattube...
@Rik_Van_Looy started
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^ French 531 was Metric OD (28.0 not 28.6) so plain had ID 26.2, and DB 26.6 (or 26.4).
Unlikely that this is a French frame though, what with it coming from Bolton.
Easy way to find out would be to stick vernier around the seattube...