Rotating an object using itween

I want to rotate an object side ways using iTween, but the thing is that it rotates the object in a very weird way in the sense that it also increased the rest of the paraemeters whereas I only want it to rotate in the Y axis.

iTween.RotateTo(gameObject, iTween.Hash("name", "SideWays", "rotation", new Vector3(0, -30, 0), "speed", speed, "easetype", iTween.EaseType.linear, "looptype", iTween.LoopType.pingPong, "oncomplete", "PauseTween", "oncompletetarget", gameObject));

Here is what I have:

[20426-joystick+issue.png|20426]

How do I get it to rotate sideways then?

I figured it out. My mistake was that I was using rotateTo rather than RotateAdd:

        var props = new Dictionary<string, object>();
        props["y"] = 60;
        props["speed"] = 40;
        props["name"] = "SideWays";        
        props["easetype"] = iTween.EaseType.linear;
        props["looptype"] = iTween.LoopType.pingPong;
        props["oncomplete"] = "PauseTween";
        props["oncompletetarget"] = _myGameObj;
        iTween.RotateAdd(_myGameObj, new Hashtable(props));