The springs are quite strong so are very unlikely to be the issue. In the same vein lubrication is not likely the issue either - it makes things move smoother but that brake will not bind just from lack of lube.
Originally Posted by
FBinNY
As I remember, Weinmann brakes allowed adjustment of the pivots (it's been dacades so forgive me if I'm wrong), so it's possible that one pivot is set too tight.
The pivots could very well be the issue, but there indeed is no "adjustment" of them per se. The pivot bolt is firmly tightened onto a bushing that prevents the bolt from pushing on the arm and binding it. The nut in the back is merely there to help lock the bolt in place. If one severely overtorques the pivot nut the inner bushing can be distended, causing the pivot to bind. Now relying on
my memory, but I believe I was able to save these sometimes by carefully filing the inner bushing.