I see. So the plane is turning itself as the tailwheel touches down. I would expect your issue is a crooked main gear which has led to you tweaking your tailwheel to make it taxi straight. At the moment you are talking about, you are light on the mains and probably still skidding a bit, then the tailwheel touches down and throws the whole thing out of whack. Do you have an issue with the plane getting wonkey just as the tailwheel comes up and maybe even again just as the mains are getting light or breaking ground? A well set up undercarriage on a Cub will give you a bump of left as you advance the throttle with the tail down, then will roll straight on its own once the tail is up, then will lift off with no changes in yaw. Landings will be a straight approach and a straight roll on the mains with little to no yaw effect (unless you do it) as the tailwheel touches down.