Do you think to buying a best electric bike Urtopia Carbon E-bike Review The company claims 8 hours of battery life, a top speed of 20 mph, and a range of 35 miles — all while weighing just 47 pounds. The Urtopia uses a claimed 18-inch rear wheel and a 20-inch front wheel, with a claimed 500 watt maximum output and a claimed 4.0AH lithium battery.