Oakley is my big red NN roo, and he occasionally feels his hormones, and would try to flog my DH. The last time I talked DH through facing him down, DH would have considered he had the victory before he did. Anyway, Oakley gets a face-off/walk down once in a while to remind him who is boss. I usually only have to do it once, since a face off includes my wheeled/sitting walker. None of my 10 roosters attack me, including the silkies, which think they are big boys. I also make a point of pushing them to the ground when it has become necessary to show dominance, pinching the back of their neck in the same manner the winning rooster does. Hold the pinch until they relax, which is submission. Not just being quiet, but relaxing all resistance. Your NN rooster seems bigger because he is taller. They have along body shape and that neck telescopes rather than raised hackles when they are being manly.
Speaking of which, time to check eggs.