the long version of the story is it started with a cherry, intact '78 Moto Grand Touring. somehow, the wheels went to a Trek 620, and then it was downhill from there. New wheels and a Suntour 6 sp, new, wider, ergo bars (I have a back problem) and bar end shifters.

So why not go to dual pivot brakes? I mean, after all, I have a dandy set of Centaurs just laying around, and some newish Tektro aero levers. (the new bars have a cable groove).

Don't get me wrong--I like the Weinmann center pulls all right, but the cable stop on the front flexes, and after (foolishly, perhaps) removing the front reflector--now the top steerer nut keeps loosening. And the cable routing gets in the way of various bags and accessories.

Then the question is, should I drill out the frame and fork for the recessed nuts, or shell out another $50 for some Tektro 539's? Or something similar?

I must add that I am a little intimidated by how thin the rear brake mount would get if it were drilled.