torqueless
Senior Retro Guru
Iirc Jack Hearne numbers are first two digits = year , so probably not a Hearne, nor a Mercian, nor a Holdsworth. Holdsworth numbers I've seen have been drive-side. That 4-digit number looks more Bob Jackson, but Jackson numbers I've seen have been central under the bracket.
That fork crown- Milremo Giro- is sort of '60s-mid '70s. The fork rake makes me think the frame is probably towards the later end of that time-span. (compare to the '64 Hearne.) The rear brake bridge looks more modern still and may have been replaced. My best guess is late '60s-early '70s. Who built it is anybody's guess- somebody who knows frame number formats/positions better than me.
That fork crown- Milremo Giro- is sort of '60s-mid '70s. The fork rake makes me think the frame is probably towards the later end of that time-span. (compare to the '64 Hearne.) The rear brake bridge looks more modern still and may have been replaced. My best guess is late '60s-early '70s. Who built it is anybody's guess- somebody who knows frame number formats/positions better than me.