"Stiff" is a very relative term here on the internet. What you might think is stiff may be perfectly normal, or on the other hand we could tell you they are ok when there is a problem. It's really hard for us to diagnose this. When you say stiff is that moving it by hand or with the servo? If it's by hand then connect the servo to the ailerons and see how it moves. If it moves ok then everything is ok. If it won't move or it binds then there is an issue to deal with. But as a rule of thumb CA hinges will be a little stiff when they are first applied, but they will loosen up with use.

Ken