Re: what did you do to your motor bike today? It's always fun having the rear wheel lock up... Had it happen to me. Doing probably 30 or so down a very, very steep hill. The chain bound up in the sprocket cover. Weird fluke accident. Locked up the rear wheel. I managed to control the skid, but since it was such a steep hill it took a long time to stop. Wore a hole right through a brand new tire, through the inner tube, and ate up the rim.... Wheels locking up is BAD. I tell you BAD.