If you need a headset it's worth considering an m part sport. The unit comes with both a 27.0 and a 26.4 mm crown race. In reality the crown race is a conical seating which is located in the race which is clipped into the bottom head tube race. Prising the clip off reveals a full complement of loose balls not a sealed bearing The upper race assembly is for an aheadset but if you only need the lower it's a means of getting hold of an increasingly rare jis headset, of reasonable quality. https://www.sjscycles.co.uk/headsets/mp ... set-black/ Should be available from other stockists too.
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin X3, Raleigh 20 stowaway X2, 1965 Moulton deluxe, Falcon K2 MTB dropped bar tourer, Rudge Bi frame folder, Longstaff trike conversion on a Giant XTC 840
