Basically, stock cush rubbers are goosed, bought the bike with 3 n half k miles on it and coming up for 2 yrs old, complained about clutch noise at 6k service, told it's "normal". Now got bout 26k on it and it sounds like the basket is trying to work it's way throigh casing. Found a fix on another forum, hinson cu216 yz/wr 450 cushes fit. Rivets ground and removed backing plate drilled to 8mm, just waiting on parts, cushes, gasket and 8mm x 1.25 stainless allen bolts then will drill and tap basket and locktite bolts. May have to grind heads a bit. Keep you posted.
All done, quiet. Will let the locktite on bolts cure a bit. So, it's hinson cu216 cush rubbers, got a pack of 8, (which was handy), m8 x 1.25 thread x 16mm long x 4mm head height, 5mm allen drive bolts, grind off rivets, drill to 6.5 mm and tap to 8 x 1.25. Locktite and grind a bit of heads down to clear oil pump chain. Refit and buzz/rattle/vibration free riding.