How can i check the dihedron of my KF2 ?

[Geowitz]

It is definitely a possibility that your issue with having to push up on the right wing is a symptom of your problem as this indicates a lower angle of attack on your right wing thus causing a bank to the right. You could shorten the back right fitting which will cause the spar to raise up where it gets cotter pinned to the fuse so you won't have to push up on it. However, you want to make sure you still preserve the washout of the wing so your stall tendencies remain friendly. This where the smart level is really the best tool for this job. You want to make the plane fly level and have as close to 1 degree of washout as you can get to maintain good stall characteristics.