Originally Posted by
Schwinnsta
On the Brompton G-line, the "lug," if you can call it that, is inside the steerer tube. I clipped a photo of the G-line from a Brilliant Bikes video.
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Interesting, thanks! I also noticed on the clone that the O.D. of the head tube was straight-wall, so thought perhaps thicker in the area of the threads/rivnuts, with recesses for internal headset bearings. But your photo of a Brom G shows just thin wall tube. 349 Broms had an externally brazed front block, so that represents a departure, and possibly different mount interface geometry on the G. The head tube is really highly stressed, I don't know if I'd want that thin a wall.