I don't like the brake feel from the stock RC master cylinder. I have a spare master cylinder from my Kawi 636 which works well with that bike. Since the RC has 1 rotor/caliper I don't think it would work correctly on the RC. Can any confirm this? Thanks!
It would be over overkill for the caliper. Most likely you would have no feel whatsoever, and it would lock up very easily.
I tried something similar with a ducati brembo on my 250 that was running a brembo 4 piston caliper, and it was still overkill.
My friend uses a ZX10R master on his ninja 300 coupled with a brembo calliper. He couldn't be happier. But he mainly rides the track so maybe it's better for his purpose?