Ok, so several weeks ago my 06 xt660x had been attempted to be stolen from outside a freinds house. The steering lock was on so the bike was dragged, bounced etc for about 100 yards before the little f****s give up on it. Handle risers were bent which i have replaced. Steering lock was sticking on which i have managed to sort. Thing is as i am riding, every now and then the bike starts to slalom, only slight at first although if i dont correct it, it progressively get worse

any ideas guys..