OK this is the reason I asked. I disconnect my batery after every ride. 2-3 days before a ride I hook up a trickle charger to avoid any problems and the battery always takes a charge. Charger has indicators for charging, 80%, and charged. Last night it charged for probably 4 hours before it showed 80%. This is after 2 days of riding and sitting for about 1.5 weeks. I had a battery die on me at the lake when we first bought the skis. It was probably old and hadn't been used much anyway so I replaced it and bought the charger. I haven't had an issues since but I've never gone mor than 2 trips and probably a month with out charging.
So is it normal for the battery to drain a little every ride?
I'm charging 2 skis on one charger with a jumper cable if it makes any difference.