I have a tarp to cover the bike however, I woke up this morning to a thunderstorm and my bike is not covered. It hasn't been raining much at all but if for instance I am away and didn't cover the bike and it rained, could it cause some problems for me in the long run? I usually cover it up if I know it's going to rain but the weather is sometimes unpredictable.

Shouldn't be a problem if ya let the bike dry out... In operation, with a lot of rain, one problem can be where water gets into the throttle control on the handbar... Many ebike designs display pack voltage (LEDS etc to display "full" to "empty") by running full pack voltage up to the display and this higher voltage is more likely to "creep around"... Fresh water itself is not a very good conductor, but dirty or salty water can be a real problem, and some folks have just disabled their power-remaining displays to remove this possible problem. Like the folks that drive exotic cars in the summer months, who wait for the first few rainfalls to wash away the last of the winter road salt, I'd probably hose down the bike in the spring to keep the salt off. My concerns (rotting wires, connections, switches etc) have always been from winter salt and slush and never from summer rains.

Most ebikes are assembled from components where the wires are all plugged together... The plugs are a possible source of problems with water and bad connections so ya might kill two birds if ya just remove the plugs and solder these connections together with good waterproof shrinkwrap to cover...

If I had a scooter-style ebike I wouldn't bother with a full cover but I *would* have a cover over the handbars and electrics mounted up there...
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Had a thought Patrick... I'm putting together a scoot next month and expect to "marinize" it for winter slush with marine-grade switches etc but I've had this thought in the back of my mind to have the wiring and connections etc also covered with a "conformal coating"... seen here:
http://cableorganizer...

I figure for a little extra cost and labour, it might trade off well as reliability and peace of mind.

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