One of my riding buddies just purchased a 2012 550. he decided to change all the fluids. He removed a bolt about 3" long with a 14mm head on the left side, thinking that was the fill plug. when he was unable to get the grease in, he called me. I showed him the fill plug on the opposite side. My question is ,does this bolt hold anything inside? I cannot find this bolt on any of my illustrations and am concerned that it may retain something. Has anyone have first hand knowledge or a better illustration on this?