Rear brake caliper will an R1 caliper fit my gen 1??????

[Captain Haddock]

If it's not leaking and the level isn't dropping it's just a bleeding problem, try cracking the banjo at the top of the master cylinder and squeezing some fluid from there as air can get caught at the top, I had that problem with mine not bleeding properly.
Wrap some rag around it though to catch the fluid.