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Not sure lol, I think there's a TO spec on the tyres for 19 & 20" (TO having some internal lining in them for road noise supression) , not sure if it's the same for the 21"
Yeah personally I’d keep it stock and OEM. Based on reports these new Ys have far better ride and suspension from 2020 models (which were basically just irons) so I’d be inclined to stick with the recommended set up until we know more.