Rotors for 2-piston Shimano BR-MT410 extremely limited?

[stompandgo]

This is not my area of expertise, so I'll fall back on diagnostic principle. What was the last thing that you changed? When did the problem appear? If the brakes were the last, are the rotors true, and is there no contact between the rotor and the pads when spinning the wheel on the stand? If it was the fork, can you put it back to the original settings?

 

[Chazmo]

Is the fork compressing to a different level now with you on it, Ringo, than before you serviced it? If so, the extension of the stanchions may have changed (probably more extended now??) while you’re riding, and maybe oscillations are occurring that weren’t possible before.

In any case, my bet is not on the fork. I think stompandgo’s advice is right on. My bet is that the rotor is slightly warped and/or the pads are making oscillating contact. Like stomp said, can you spin the wheel on the stand (or off the ground) and watch the brake contact?

 

[Gionnirocket]

Is the wheel mount a through bolt or drop out?
If the latter, make sure it's fully seated.
Sometimes it's hard to do in a stand. When back on the floor, loosen the release, wiggle the wheel and tighten the lever. Then double check your pad/rotor clearance.

 

[Ringo9]

This is not my area of expertise, so I'll fall back on diagnostic principle. What was the last thing that you changed? When did the problem appear? If the brakes were the last, are the rotors true, and is there no contact between the rotor and the pads when spinning the wheel on the stand? If it was the fork, can you put it back to the original settings?

Rotor was indeed the last thing changed, together with the post mount adapter to push the caliper further out where it needs to be for a 203mm rotor (previously mounted directly on the fork with 160mm rotor).

Few days before that I played around a bit with fork settings and pressure to bring the behaviour more to my like as I'm new to this and didn't have a baseline to judge whether the existing setup was good or bad.

Thing is, I can't be sure I went "hands off" before changing the rotors and after playing with the fork so I can't be sure it was indeed the rotor or the fork.

Now, fork settings and pressure I can more or less revert to where they used to be, I think I can recall those values.
Rotor seems to be true. There was some touching of the pads at first but I fine tuned the position of the caliper and the wheel now spins freely when in the air.

If the fork just so happened to break/need a service right after those events it would be quite a coincidence but as I said the bike just clocked 1000km so for a cheap fork it may not be that unusual.

Last thing I can always do is put back the stock rotor (and remove the post mount caliper adapter) so I can eliminate new rotor being the cause, I just didn't want to jump straight to it.

@Chazmo That could be because of the extra air pressure I added recently, going from 90psi to 130psi. But I'll revert that and check.

@Gionnirocket the wheel mount is a through axle bolt.

 

[Gionnirocket]

Rotor was indeed the last thing changed, together with the post mount adapter to push the caliper further out where it needs to be for a 203mm rotor (previously mounted directly on the fork with 160mm rotor).

Few days before that I played around a bit with fork settings and pressure to bring the behaviour more to my like as I'm new to this and didn't have a baseline to judge whether the existing setup was good or bad.

Thing is, I can't be sure I went "hands off" before changing the rotors and after playing with the fork so I can't be sure it was indeed the rotor or the fork.

Now, fork settings and pressure I can more or less revert to where they used to be, I think I can recall those values.
Rotor seems to be true. There was some touching of the pads at first but I fine tuned the position of the caliper and the wheel now spins freely when in the air.

If the fork just so happened to break/need a service right after those events it would be quite a coincidence but as I said the bike just clocked 1000km so for a cheap fork it may not be that unusual.

Last thing I can always do is put back the stock rotor (and remove the post mount caliper adapter) so I can eliminate new rotor being the cause, I just didn't want to jump straight to it.

@Chazmo That could be because of the extra air pressure I added recently, going from 90psi to 130psi. But I'll revert that and check.

@Gionnirocket the wheel mount is a through axle bolt.

The other common causes of wobble are loose, worn headset bearings and spoke tension so you can check these...
Sometimes coincidence can be a some_ma_na_bitch
But I agree... Go over what was recently touched.