Pulling to the right slowly

My heewing t2 vtol slightly pulls to the right. It will do a circle in about a 1/4 mile radius. Im using dshot so its not esc calibration. My rudder is dead straight. It feels like one motor might a little more powerful. Or could it be the 5% differential thrust? Im going to disable it. I have roll and pitch osd and it looks like its not rolling. Ive calibrated accel axis a few times without a difference.

Any ideas where i should look? In manual the plane flys great. Its just going in a straight line. Iā€™m slowly turning right. Feels like a very slow yaw.

I also have tilt vectoring disabled in fixed wing. Plane flys better without it.

What flight controller do you have? Have you done the temperature calibration?

Basically the gyro drifts as it gets hot. So temperature calibration reads it over a temperature range.

Heeeing fx-405. I have not done temperature calibration. How is that done?

Sorry i just re-read your post, I thought you were getting the lean when it was hovering. have you trimmed the aircraft control surfaces ?

https://ardupilot.org/plane/docs/auto-trim.html

Yes i have. Its like a slow yaw. I can make a circle but very slowly

do you have a log of the flight.

No it happens right away. I have tilt rotors. Im thinking one is not perfectly straight during forward flight.

so it flies ok when in manual mode but when you enable stabilise or fbw it starts to circle?

In both. Its very suttle it takes like 1 km to do half a circle

that sounds like something mechanical, do you have BDSHOT enabled to see the RPM of the motors?

Yeah i have dshoot 600. Would one rotor slightly up or down cause a slow yaw. The left motor tilt sero looked like it was slightly up. Like a friction of a mm

yes if the left motor is pointing up a little then it would roll it to the right.

I think it was my accel calibration. The roll axis was a positive value. When i re did it with just the fuselage the numbers changed to a smaller negative value.