1 1/8 silver or black threaded headset
Having looked at your other post (the chrome frame), I think you'll find you need a 1'' headset. The sizing refers to the external diameter of the fork steerer tube, not the internal diameter of the headtube.
@Bearlegged started
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Having looked at your other post (the chrome frame), I think you'll find you need a 1'' headset. The sizing refers to the external diameter of the fork steerer tube, not the internal diameter of the headtube.