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A few years ago I experienced the exact same judder on the front brake on my road bike. I couldn't get to the bottom of it, multiple bleeds, sanded pads and rotors and it still happened. It only stopped when I replaced the rotor and pads :( it was annoying not fully knowing how/why it was happening.
@M_V smaller rotors is obvs technically going to be stiffer but the 220mm+ rotors are thicker (2.0mm - 2.3mm). I use 220m rotors on my mtb and theres no more rub than on a 200 rotor. The extra power is great for my current 101kg dad bod...
Going on anecdotal evidence of how much harder it is to true compared to 1.8mm 203mm rotors, I'm not so sure.
Either way, it's previously worked fine. I might change pads, see if that helps.
Or use the brakes less.