In a friction drive motor, a small, solid wheel rotates against the side of the tire in order to drive it. The first motorcycles used the same concept, with a motor mounted above the front wheel. The problem is that the drive rubs at the side of the tire. It's inefficient, and it quickly wears the sidewall away. Tires need to be replaced every couple hundred miles. For this reason, you'll seldom see electric bikes with this type of drive anymore.
This article first appeared in Electric Bike Report in June of 2013. Since then, we’ve made some changes to our motor selection - our Direct-Drive motors are now all High-Torque 6x9 wound, so they run slower (approximately 15mph at 36v or 20mph at 48v), and our Geared Motors have been replaced by a 500w version, (approximately 20mph at 36v or 28mph at 48v). The Direct-Drive is now our Heavy-Duty motor and the...
“Built to be portable and highly customizable, the Stark Drive Mini e-bike will provide you with everything that you desire for your commute and everyday use. The Stark Drive Mini can easily be folded after you’ve arrived at your destination and conveniently carried into the office or classroom. The Stark Drive is also compact enough to be taken on a plane (adhering to FAA & TSA guidelines), giving you increased mobility wherever your travels take you.”
Duke Eco-Marathon Team using an Electric Bike Technologies hub motor for the 2014 Shell Eco-marathon. The E-BikeKit motor provides optimal space saving because it does not require a chain (this makes it great for converting road bicycles to electric bicycles, which is what it is designed to do) but we hope to determine if it provides us with a better overall vehicle efficiency than our outboard motor.
The Super Commuter is very aptly named. The 350w Bosch motor will help you sustain speeds of up to 28mph, and the burly, 2.4-inch wide, Schwalbe Super Moto-X 650b tires will keep you secure on even the roughest city streets, and Shimano Deore hydraulic brakes provide ample stopping power. Fenders provide welcome protection from road spray so you arrive at your destination fresh, integrated lights are critical for post-sunset riding, and a side-view mirror hanging on the left side of the handlebar gives a great view of traffic around you. After all, you can ride at the speed of urban traffic on the Super Commuter.
Electric bikes are here in a big way. Liberated from some of the normal constraints of standard bike design like weight and gearing, e-bike design has exploded; if you can imagine it, someone has built it. From cargo bikes to city bikes, messenger bikes to mountain bikes, road bikes, and even beach cruisers, there is something for everyone. The beauty of e-bikes is they make the joy of cycling accessible to so many people in so many ways.