akschu,
it sounds like you motor is leaning out as you fly/climb. This is normal when you are flying. You should adjust your motor on the ground knowing this is going to happen. When you are adjusting your motor on the ground get it to where you want it running and then open it up another 2 or 3 clicks. This will richen it up a bit so that when it leans out in the air it will be running where it should be.

Hope this helps.