See the gears above the rear fork? That motor powers these puppies up to at least 50mph. Crazy fast speeds cost a bundle. Prepare to pay at least $1,500 on top of the cost of the trike to get one of these.
It's definitely an experience you'll never forget. Their videos are amazing! Pretty scary stuff. These guys don't just sell power kits. If you're not up for the high speed stuff, then FFR also sells the trikes in stock condition:
The toughest part about an electric setup for me to swallow is the location of the batteries. To generate the power to push the trike at high speeds requires some pretty hefty sized ones.
Where to put 'em? This is the cleanest setup I've ever seen. The battery enclosures look good too!