OD of stem not steerer.. got a tube stem raiser, they flare in the center so OD on the wedge end is ID on the upper end..

Have one, of the 3 made ,, the 1" , 7/8" & 13/16" (from J&B) have a 1/16" tube wall so OD on the top is wider.

https://harriscyclery.net/sitesearch...iteSearch.y=19 Used them to make threaded forks take threadless stems.. in the LBS..

Brompton has a 1" quill that goes in their fork, threaded headset... 36mm headset wrench.

And 2 bike Fridays; 1) a 9/8 , & 1) a 1& 1/4" 40mm headset wrench (CK Grip nut headset)







....