I apologize David and Canyncarvr,I think there has been a unfortunate misunderstanding on my part.I was for some reason thinking that you were dealing with the OEM bearings and actually removing the outer seal completely,thus having a exposed bearing,similair to what Yamaha does.(should have read your posts better).The small rubber seals on these bearings are indeed just a dust seal,if these bearings were continuously exposed to water or another form of contaminant it would penetrate between the inner race and the dust seal and destroy the bearing.You are correct when going to a aftermarket bearing and removing the innermost seal and leaving the outer seal in place ,only removing it for bearing repacking,where you would be forcing the contaminated grease out and fresh grease in.If you are having a problem with water entering the bearing might I suggest a small trick,apply a layer of grease @1/8 thick on top of the bearing,once the spacers are in place the grease will provide a extra barrier to help prevent water from entering the bearings,just scrape the old grease out when you take the wheel off and reapply fresh grease when you replace the wheel.you should find that the bearings stay cleaner for alot longer.
Again sorry guys,James.