I've been racking up miles on my FD, however my tank is only good for about 10 miles if I am doing a lot of hill climbing. I do find myself doing a lot of pedal assist with the FD, perhaps my mileage will get better. I think the manual states .7 liter, that's not much, I don'f think the FD's are is efficient as the chain drives. The 2.5 HP 2 stroke is powerful, it will pull pretty hard from 10 MPH to 30 MPH, sweet spot is about 23 MPH.