If your going to run extension cords for the tenders buy a Golden rod and place it under the bike and cover it. If you can't get the Golden Rod go to a music store, and buy a piano damper rod (same as GR only outside is plastic not aluminum, cheaper too). Mount the rod on a 2X4 or 2X6. They are 40/50W and will keep all the condensation off the bike. They work down here in Fl. with all the moisture we have here and I use them under my bikes and in the boat.