Your right Mark I have passed on my insights to others. Against my own better judgment I had a dural and hard anodised sprocket made. Waste of time. Although if you ignore the sqealing long enough the sprocket will quieten down and function ok for up to 10k I feel. I would just have liked the benefit of your experience earlier, vocalised through my dealer perhaps. I have always said that the factory have played fair with me but it has also been on the understanding that we as customers maintain some discretion. Yes these forums are emotive and sometimes intemperate. My intemperance is justifiable on the basis that: I believe that that being informed that a cracked chassis is due to hard use by the customer is unfair and untrue. If of course hard use is doing 18000 miles in two years then I am guilty as charged.