Originally Posted by
cyccommute
Just brazing the crack isn't going to fix it. The cup of the headset is a press fit so it must fit tightly. The crack has increased the diameter of the headtube so the headset fit is going to be affected.
I haven't done
frame repair, but I've done braze and weld repair. Someone who knows how to braze will add material (braze) to the headset tube. This will decrease the inner diameter, done right. After the repair, some metal (braze) will have to be removed (with a reamer) to fit the new cups anyway. If properly done, they will press fit again. Key here is to determine the root cause. Accident? Bad material? Bad cup install? Improper size cups? Determining the cause will influence the remedy. Otherwise I'm in full agreement with what you said.
I'm not going to say that brazing the crack is the proper way to repair
this frame, but I don't see a crack braze repair as being incompatible with press fitting new cups. Brazing adds material. If it were my bike, I'd most likely braze an additional piece of steel across the crack, to beef up the area. I wouldn't presume to make it look like it was before the crack, just make it safe to ride. It will leave a "scar" if you will.
I was thinking the polished parts were stainless. Being chrome will complicate things (cosmetically).