Cost: Good e-bikes are not cheap, and unlike most bikes, the costs associated with owning an e-bike don’t end when you hand over your credit card in exchange for a shiny new steed. The average cost of operating an electric bike is around $390 a year, including maintenance and charging. You’re also likely to need to change the batteries every 3-5 years so factor that into your costs.
The leading U.S. developer and distributor of electric bicycles and electric scooters, Currie Technologies offers a wide range of proprietary E-bike technologies across several bicycle designs. In order to meet the needs of its target market, Currie offers a wide variety of bicycle types with varying intended uses and at a variety of price points. With a Â“good, better, bestÂ” approach to E-bike marketing, Currie starts with its EZIP brand for opening priced bicycles which are primarily sold through mass market and web-based retailers. The IZIP brand is reserved for its mid- to high-end offerings, sold primarily through full service, specialty retailers.
Torque sensors and power controls were developed in the late 1990s. For example, Takada Yutky of Japan filed a patent in 1997 for such a device. In 1992 Vector Services Limited offered and sold an e-bike dubbed Zike. The bicycle included NiCd batteries that were built into a frame member and included an 850 g permanent-magnet motor. Despite the Zike, in 1992 hardly any commercial e-bikes were available.
Certainly not for the entry-level e-bike buyer, those who need to strap cargo to their back now have a new option with the Riese & Muller Load option, with full cargo space on the front of the bike. While over $6,000, the full-suspension bike has adjustability to allow for differing loads. Safety features include LED headlights and premium components abound.
Controllers for brushless motors: E-bikes require high initial torque and therefore models that use brushless motors typically have Hall sensor commutation for speed and angle measurement. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. The controllers generally allow input by means of potentiometer or Hall Effect twist grip (or thumb-operated lever throttle), closed-loop speed control for precise speed regulation, protection logic for over-voltage, over-current and thermal protection. Bikes with a pedal assist function typically have a disc on the crank shaft featuring a ring of magnets coupled with a Hall sensor giving rise to a series of pulses, the frequency of which is proportional to pedaling speed. The controller uses pulse width modulation to regulate the power to the motor. Sometimes support is provided for regenerative braking but infrequent braking and the low mass of bicycles limits recovered energy. An implementation is described in an application note for a 200 W, 24 V Brushless DC (BLDC) motor.
E-bikes mostly use motors and battery options from a few major suppliers: Bosch, Yamaha, Shimano, and Brose. A few other brands exist, but are less reliable or powerful. Some, like the Yamaha system, have more torque and others are quieter. But generally all four make good options. Look for motor output (in watts) which will give you an idea of total power. But watt hours (Wh) is perhaps a better figure to use—it takes into account battery output and life to give a truer reflection of power.