Old tandem headset
I've picked up an old tandem fram of unknown origin. No serial numbers/make etd.
It seems to have an unusual head tube with integrated crown race.
The man in my LBS was baffled.
What kind of headset/bearing and forks might be compatible here?
The outer diam is 45mm and inner is 33 of what looks like a crown race
Dan, I hope you are sorted by now but the headset does look to be a Brampton, the most common for tandems around the 30s-50s period. You would need a crown race, top frame race, the clip as shown and at least a locknut. There will be a race squeezed into the lower part of the head tube to meet the crown race bearings, 3/16" dia but this is very likely to still be there and there should be a bearing race squeezed into the clip. The remaining headsets of the period were mainly either Royal Enfield or Chater Lea. I live in Hampshire and would be willing to help if you could get to the Southampton area, Dave.
Incidentally the frame looks to be possibly a CWS Federation or J Grosse.