Okay, here's a newby-type tech question... My bike's got 14,700km on the clock. Over the past week or so, I've noticed an occasional rattle or clunk through the bars when passing over sharp transverse ridges in the road surface. Nothing major, the bike doesn't move around on the road, and it doesn't do it every time I hit a bump. It's only a small noise/sensation. But I can feel it, and hear it, and it didn't use to be there! There doesn't seem to be any looseness in the bars & forks otherwise, and the bars turn evenly and smoothly through their arc. I can't duplicate the feeling by pushing or pulling on the bars when the bike's stationary. So...something in the front suspension that only appears on short sharp impacts? Bearing problems? Any ideas?