Hi!
Every modelairplane should be trimmed at full power...that's a good rule to follow.
If the airplane climbs at full speed then do something about it!
The first thing to do is to check the elevator setting , second: measure the wing, stab and the engine thrustline with a Robart incident meter.
On most airplanes which are lowwinged and midwinged the incident should be 0 degrees on all these 3 positions.


Regards!
Jan K
Sweden