I have a logo 550 , spirit 1.1.0

When stopping a negative pitch pump the heli bobbles to the left, and quickly recovers

The swash is level throughout the pitch range. Pitch pump boost is 0, cyclic gain is 85, pyroette consistency is 175

I am not sure what to do to tune this out,

Suggestions?

You can try to decrease Cyclic Gain (85% is mostly too high) and check Geometry 6° value.

Is your rudder holding well? If not, it can induce aileron movement. When you enable Subtrim (tuning) are the servo horns at 90° and blades pitch at 0°?
Also make sure, that the unit is mounted really hard. Do you use our double sided tape?

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Spirit System developer

I used the tape supplied with the unit
I will check to be certain the unit is securely mounted

Horns are at 90 during subtrims. Swash is level throughout pitch range. 6 degrees was carefully set.

I will try a lower cyclic gain

I have a Logo 550. I do not have any issues in flight.
The issue of the servo being at 90deg is a little grey sometimes. We can put the servo arm at 90deg to the servo case, but once mounted on the heli, the serv arm is not 90 deg to the servo to swash rod. If we made it 90 deg to the servo to swash rod would it make a difference.
thanks

We have also Logo 550sx for testing and works pretty good without special tuning.

Mikado helicopters have often not very precise geometry, correct servo horns are needed or servo travel adjustment can be used.

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Spirit System developer

I am using correct horns, and have good geometrY and also , I said My swash is 100 percent level throughout the entire pitch range,

It's only on a negative pitch pump that I have any issues. When i abruptly stop the pitch pump the disk drops to the left about 4 inches measured at blade tip.

It might be that the pitch (left) servo is moving faster than the other two, during my abrupt stop of the pump

I try a lower head gain and check the mounting is secure this Saturday