All plastic and rubber items exposed to heat, pressure on road dirt, and will sooner or later degrade to the point where they are no longer effective, in this case to reduce heat and vibration going through to the carburetors. The simple answer? Replace them with new Honda items. To make the most of your order, check the online catalogue and 'parts list' fiche for all the other consumables and spares you may need to complete your service or rebuild.
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