nope never banged them, must be a manufacturing defect, 3 have fractured, didnt notice untill i was cleaning them today, i thought it was only one, got home to put the 17s back on and checked the others, and......another 2 have started to go aswell, i will post pics up depending on what the comapny will do, as i dont want to name and shame just yet, would rather give them the chance to replace them and rectify this