Originally Posted by Poolside
Put the work clamp near to the weld, sand off some paint to make a good contact.
Maybe repack the bearing?
Do not clamp on anything supported by the triple clamps, the current will flow through the steering head bearings to complete the circuit and cook 'em. Clamp on the frame
as close as possible to the steering head.
I'd cut a piece the same size as the one on the frame, champher all edges (3 on the new piece and 3 on the frame) and your buddy can run a horizontal bead around the bottom of the frame piece and on top of the added piece. The bead will lay down in the groove leaving more weld surface area than plug welds.
Edit: I'm too slow. My DR650 frame is mild steel, any scrap metal he has will work.