my 4*40 turns left when im in a gentle climb, it looks like im giving it left rudder,what would cause this? when i do fast loops it seems fine. the trim on the rudder is ok, it flys nice and straight when im level. thanks Larry

Sounds like a thrust problem. Take a couple of small washers, and stick them under the left side of the motor mount. This will make the engine sit to the right. I've got 2 washers under my mount on each left hand hole on my 4* 60.

Deadeye is dead on with this one. it beats off setting the rudder and overcomes what is called the P factor your prop and engine produce.