The future is now, and the future is e-bikes - here’s how they work and why you need one in your life
An e-bike incorporates an electric motor to a traditional bicycle frame to deliver power assisted pedalling. They’re designed to help the travel further and faster with less effort, providing the extra little bit of oomph you need to top out on steep climbs or helping you keep pace with fitter riders. Unlike on a moped there’s no throttle, but you are able to choose from varying assist levels on most models.
Well, here are five reasons:
1. Electric bikes are especially useful in hilly areas. They’ll help you transport heavy loads over long distances with relative ease, which for some people can eliminate the need for a car.
2. They’ll deliver you to the office smelling fresh. And your colleagues will thank you.
3. E-bike owners ride more. Fact. A recent report by the Transport Research Laboratory showed that regular bikes are ridden fewer than 25 times a year, with 46% being used only one or two times a year. In comparison, nearly a third of E-bikes are used at least once a day and 81% of owners use them at least once a week.
4. The average e-bike costs the user 5p-8p a mile. Compare this to around 40p for the average car and it’s not hard to see why so many people are swapping their traditional bike for a power assisted model.
5. They’re fun! So fun.
You do. The motor is there to give you a helping hand – it won’t do all the work for you.
By law, all e-bikes are limited to an assisted speed of 15.5mph. Pedal faster than this and you’ll be moving without any help from the motor.
The Ridgeback E-Flight Di2 2017 uses Shimano's STEPS E-Bike sysem, and featured hub gears with automatic shift mode.
Electric road bikes help you to ride harder for longer. | Photo: Giant bikes
E-MTBs typically feature a large capacity 500wh battery, giving you a range of approximately 25 miles on full assist mode. | Photo: Giant bikes
The range of an electric bike is determined by the capacity of its battery: more power stored equals a greater number of power assisted miles. Some manufacturer will give a power rating in Wh – Watt hours – and some in Ah – Amp hours. But it’s easy enough to convert between though two and compare across brands. To go from Ah to Wh take the Ah capacity and times it by the battery’s rated voltage (usually 36V); for the reverse simply divide Wh by rated voltage.
Brands will sometimes specify a battery’s range in miles, but take this number with a pinch of salt as variables such as headwind, hills, tyre pressure, increased weight on the bike and speed will all affect performance.
As a guide - and for a conservative estimate - divide a battery’s capacity in Watt hours by 20 to get a rough idea of the number of miles you’ll get out of it. So, for example, you can expect to get at least 18 miles from a 360Wh (36v 10Ah) battery using full assist mode.
Bikes with a LCD display will show an updated range as you ride, so you know exactly how much juice you have left in the tank.
E-bike motors come mounted on either the wheel hub or the crank drive. And although crank drive motors are widely recognised as the superior of the two, there are advantages and disadvantages to both.
Hub drive motors are usually attached to the front wheel and offer a cheaper alternative to crank drive.
Hub drive are by far the most common type of motor on electric bikes for the simple reason that they are cheaper to produce and easier to fit than crank drive motors.
The advantages of a hub motor are:
- Relatively simple in design, so require little in the way of maintenance.
- Should they require maintenance, they are easily accessible.
- Cheaper than crank drive motors and more than capable on flat terrain.
The disadvantages of a hub motor are:
- Can only deliver full power at one speed, so tend to struggle on steep terrain.
- Draw a high load at low speeds, which flattens the battery more quickly. To travel efficiently you must maintain a constant speed.
Crank drive motors typically feature a sensor which measures speed and cadence and adjusts the assists level accordingly. | Photo: Ridgeback
An LCD screen lets you know exactly how much juice you have left in the tank. | Photo: Ridgeback
The higher the assist level; the shorter the bike’s range. So on longer journeys it’s best to select a low level and dial it up as and when you need a bit of extra help.