Trimmed to fly straight is very different from taking off. There are several issues here, engine torque being one of them. Rather than doing anything to the ailerons during take off other than to keep the wings level, try a little left rudder once the wheels leave the ground.

For normal flight, the trim will vary slightly from flight to flight depending on how things are mounted. Once the ailerons are trimmed for straight flight, they pretty much will stay there with only a couple clicks from time to time, usually on the first flight of the day. The elevator trim, however, works only for one throttle setting. If you add more throttle, then probably will require some trim to get straight and level flight. But that's not your problem, is it. Try a little left rudder rather than ailerons (unless the plane is banking.. which is different from turning).

DS.