I agree with choom78 - if you've gone from drum rear change bias valve and adjust handbrake, should be better.
If need freshen it up new lines, discs and pads. Zenki and Kouki have the same size rotors (231x10mm) and pads etc.
Only difference is the style of the caliper (kouki flips open to change pads - zenki need to knock out slides/shims)
