The gauges on Harleys are prone to fogging up and staining the under side of the lenses. This is a common thing and the dealer will usually not do anything to remedy the situation unless damage to the instrument occurs from the moisture.
Best bet is to avoid the instruments and gauges when washing the bike and if you get moisture in them, park the bike in the sun for a while which will usually evaporate the moisture.
Best bet is to avoid the instruments and gauges when washing the bike and if you get moisture in them, park the bike in the sun for a while which will usually evaporate the moisture.