Thanks 4 the replies!

I have an idea of what can cause this (special thnx to Acropilot_ty )
the fuselage has a curved shape on the top and an almost flat bottom aft the wings. So when its sideslipping it can generate some lift pulling the rear part towards the canopy. Something similar may happen at the cowling in the opposite direction.
Please tell me if you think this sounds believable.

regards,
Zaquron