My front calipers have two 28mm and two 32mm pistons per side. The total volume is less than you'd think. The rears use 28mm and 30mm pistons. Again, fairly low volume.
The manual master has a 1-1/8" bore.
If you're getting more than .010" pad movement then something is wrong. Brake pads normally ride a couple thousandths of an inch off the rotor. Anything more will lead to a squishy pedal.
We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind. - Stu Harmon
