I actually ran into this exact same issue with a client's Yamaha U1 last year, those OEM plastic bracket bushings wear out or crack way too easily and cause an annoying rattle. Instead of waiting weeks on a backordered part from Yamaha, I ended up ordering the 14mm O.D. / 8mm I.D. Yamaha pedal rod bushings from Pianos Bolduc, and they slipped right into place perfectly. If you're in a pinch and need it fixed today, you can also just grab some thick damper rail cloth or heavy bushing felt, cut it to size, and bush the bracket manually; it actually dampens the mechanical noise a bit better than the stock plastic anyway.
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Mark Purney
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