I have a 97 model 800 Marauder. Supposedly the engine was just changed out and the engine cranks right up and actually sounds good, but there is a rattling/slapping sound in the front cylinder and sounds to be towards the top and front. It has excellent compression, the plug shows no metal, the valves have proper clearance and the timing chain is tight. I am thinking there might be some loose debris like a bolt or nut in the crankcase or on top of the piston. It actually sounds like there is noise at the top and the bottom of the Cylinder. Has anyone experienced this and/or what do you think it might be. I´m down to removing the head,but haven´t yet.