Put some oil in it and gently work it in....there isn't much to go wrong in those engines. The "bearings" are actually bushings so chances are it's just stiff from sitting so long. I had a Saito .72 that was very stiff after approx. 5 years of hanging on the wall nose down. I just worked the prop back and forth a bit and it eventually loosened up. That engine runs like a top now.

CB