Dihedral Question

[Robin G]

My mod 3 wants to roll to starboard. We have checked and rechecked the rigging and the only thing we can find is a difference in the dihedral of the starboard and port wings. The port wing has an angle of 2.2 degrees and the stbd is 1.5 degrees. In the opinion of anyone more informed than myself, is that sufficient to induce the roll? Also does anybody with a 3 know the recommended dihedral for the wings. By the way, the washout is almost identical on both wings.

Thanks in advance for any input.

robin g