Just curious - downtube shifter mounts are normally welded/brazed to the tubing without a hole, or with a small hole where the 5mm screw goes. Did this bike have the braze-on mounted over this large hole, or did you grind through the tube while trying to grind off the braze-on?

My non-framebuilder opinion is that Surly tubing is likely thick enough to tolerate this hole, and that you could seal it and reinforce it with some judicious use of fiberglass and resin packed into the hole.


But I bow to the professionals: