I have had a Shimano e8000 motor on my Focus Jam2 for over two years. I transport it on my towbar rack in the rain. I ride in the rain and through puddles. I wash it (but not with a hose, I use a watering can without the rose)). I have never had any electrical problems. When I removed the motor cover guard, all I find is dust or a thin brown stain where the dust got wet.
Unless the Norco has a weird shape that channels water into the motor, I would not worry.
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