The brakes on my 6-speed bike were struggling to release on my ride today. Salt and grit have got into the callipers and cables. I just had a look but have only made minor improvements. It's getting late - I will try to finish the job tomorrow.
I just got back to work on the brakes...
I would have liked to remove the callipers, dismantle them, clean and grease the pivots, then put it all back together again. It turned out, however, that corrosion was making it very difficult to undo the allen 'nuts' holding the callipers in place. I didn't want to risk using too much force in case I stripped the allen heads so I had to compromise...
I loosened the one pivot that I could on each calliper and cleaned and greased those before retightening them.
I couldn't do that with the second pivot on each calliper though because of those corroded allen nuts, so I made do with cleaning everywhere that I could and then squirting GT85 over the pivots, and also up inside the brake cable outers. I worked the callipers open and closed repeatedly until they finally loosened up.
The brakes are working properly again now.
I noticed that there isn't much life left in the brake blocks. I will replace those after another ride or two.