Originally Posted by
Turd Ferguson
Dual Pivot,
From you post I'd say it's over-tight fixing bolt. Is that the bolt that holds the cable, or one of the bolts that holds the caliper into the frame?
The bolt you're worried about is the one that fixes the calipers to the frame. Back it off a bit, then follow the directions on the ParkTools page referenced above for adjusting tightness and centering. The problem's not with the cable, it's a small fix on the brake itself.
Springs rarely go bad on caliper brakes. I mainly fix up old bikes from 70s and 80s with crappy old centerpull and low-end sidepull caliper brakes, and I've never had a bad spring.