The Path does do some serving of electric bikes. Can't say what it would cost to do your tires, but I wouldn't hesitate to take my bike there. It's a great shop.
They might charge you an arm and a leg to do it. Any way you could do it yourself. Come by The Bicycle Tree to get familiar with how to fix a flat. They only work on regular bikes. But you can learn how to do it and see if it can help you. I'm going to be there at 3:00PM today. Let's look at it.
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