Hi i just put on a Scotts sharkfin very bling. as i was admiring it i noticed that when i spun the rear wheel the spacer (butted against the swingarm) spins. as i had not noticed this before i am concerned whether it is supposed to. if so would it not wear the spacer down quickly against the swingarm. i assume that is why there is a metal plate screwed to the swingarm at that point.