Advice on rear sprocket please... I just spent some time in the garage cleaning the chain and sprockets on the 916, and noticed some side-to-side movement on the rear sprocket. I don't remember seeing this before, so I guess something is wearing; there's no sign of metal flakes anywhere (yet?). So: How much movement is acceptable? What is the likely cause? What are the options (and cost) for rectifying it? Thanks in advance Andrew |