Here is a new device out on the market to help you keep track of the current state of your battery, and warn you of impending failure so you can replace it before it surprises you. It is advertised as waterproof and for use on both bikes and watercraft, so I suspect it is. Amazon.com carries it for about $50. If you order one, make sure you get the model made for motorcycles (BB-SBM12-PS) , since they have more than one type. http://www.argusanalyzers.com/ Here is the direct link to motorcycle unit. http://www.argusanalyzers.com/battery-monitors/products/bb-sbm12ps-battery-bug-battery-monitor-argus-analyzers.html