It's not worth it. First, I believe conventional wisdom is you can recover 1-3% of total battery capacity, which in a 400Wh pack might be as little as 4Wh, or

It's not worth it. First, I believe conventional wisdom is you can recover 1-3% of total battery capacity, which in a 400Wh pack might be as little as 4Wh, or one AA battery worth. Second, you can only actually do regen with a hub motor, but mid drive is much more popular.