… extremely popular in Europe, they are on the rise in North America as well. There are a couple of different systems currently on the market like mid-drive or rear/front wheel assist. The rear/front wheel assist gives you the option to just use the throttle without pedaling. The weight is either in the front or the rear wheel (hub). Mid-drive systems provide power through the cranks of the bike. With most e-bikes, the mid-drive assist enhances your pedal stroke – so you must be pedaling.