It's not quite an A-head stem. The steerer is threaded and the headset is conventional, with a separate locknut. The stem clamps to a small diameter quill that's brazed into the steerer. You sometimes see the same arrangement in early mountain bikes.bm0p700f":4eel6d40 said:Ahead stem in 1938 well that I never knew about.
True :idea:creindesign":2jgkcntc said:Just a thought: if you would put the driveside crank on - use that as a lever to block the BB axle - undo the first nut.