How does the handbrake actually work?

[georgecook]

I have been following the "brilliant" threads on here regarding dismantling the rear callipers. Have checked the bores, and seals and armed with the correct seal kits am now ready for reassembly. I will follow this to the letter, however I would feel a lot happier in my work if I could understand exactly how the handbrake operates and why the cable adjustment is so critical. (thick as a brick) george

 

[harveyp6]

Inside the caliper, the handbrake works exactly the same as the footbrake, it just uses a different piston to operate the same parts, and that piston is operated mechanically instead of hydraulically.
The handbrake cable needs to be adjusted so there isn't any free play, but it's not so tight that it holds the handbrake levers (quadrants) on the calipers off their stops at rest. If the cable is too tight, and the quadrants are off their stops at rest, then the calipers won't self adjust to compensate for the pads wearing. When fitting new pads the calipers need to be operated to bring the new pads up to the discs, then the cable needs to be set as described previously.