donaldosaurus, who is on tour in Italy at the moment, has just had a similar problem. It was so noisy that he was worried that the rear wheel bearings may have been failing. He has a can of silicon with him and a spray with that has resolved the problem for the moment.

It is a bit strange because I understood that belt drives on bikes are used to reduce noise by comparison with chains. Is there some sort of alignment problem with the M3W?

It makes me wonder if some sort of enclosure would not be a good idea. At one time enclosures on rear bike chains were not uncommon.

Peter

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