Seems a good zombie to resurrect, as I'm in the same situation Jethin was and have a related question:
Could going from caged bearings to loose balls resolve the issue? I'm working with a '71 Campy headset. When I brought the bike home the steering was super-stiff, and I discovered the bearings had been installed upside down. Now that they're in correctly I can't get that sweet spot with zero play and no appreciable resistance.
I'm wondering if the bearing cages may have been damaged by the incorrect installation, as there's no pitting or scoring in the headset itself to suggest a problem there.
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A race bike in any era is a highly personal choice that at its "best" balances the requirements of fit, weight, handling, durability and cost tempered by the willingness to toss it and oneself down the pavement at considerable speed. ~Bandera