The basics of an e-bike are not dissimilar to a standard cycle, everything is there as normal with the addition of a few extra components


Early e-bikes used a throttle type controller which delivered power to the cycle irrespective of whether or not the rider was pedalling. Thankfully these have been superseded by power assist (or pedelecs). Power assist bikes in contrast, measure the torque generated by the rider and deliver additional power proportionally in line with the effort put in. Throttle assist bikes are now no longer legal to sell in the UK if they deliver more than 4mph.

Pedalecs deliver a more natural connection between the bike, motor and rider. The rider can choose the level of pedalling assistance required to suit the gradient, overall speed and rider preference. Within the UK an e-bike can legally offer power assistance up to 25kph (just shy of 16mph), after this point the motor will cut out and the rider is on their own until the speed drops in which time the motor kicks in again.

Entry level bikes tend to use a hub mounted motor, they can deliver a good level of performance at a reasonable price point (often half the price of their better quality frame mounted counterparts). The downside to hub driven systems is the loss of quick release wheels making roadside puncture repairs difficult and requiring the use of several additional tools. In addition they become harder to transport as they cannot be easily packed down to fit into the boot of a car etc. Weight distribution is less than perfect as the heavy motor is mounted to the steering which becomes evident in the bikes handling.

The current motor of choice is frame mounted, this dispenses many of the gremlins associated with hub driven models that can put off the more performance orientated rider or less mechanically competent person. The whole frameset is designed around the motor which sits centrally on the bike at the lowest possible point , this helps keep the bike more lively and nimble. As the motor pulls the chain rather than driving the hubs, this system allows the use of quick releases as there is no hard wiring between the motor and wheels. Another big benefit of frame mounted motors over their hub driven units is their lack of drag whilst freewheeling. Hub motors have a noticeable amount of resistance whilst power is not engaged. As frame motors use standard hubs it is far easier to pick up speed whilst rolling downhill once the maximum assistance point has been achieved.

There are currently motors on the market for specific applications.

City bikes, folders and upright leisure machines are often built around a gentler motor that delivers the maximum permissible top speed but packs less torque and accelerates in a more sedate manner.

Commuter bikes and hybrids often have an intermediate motor which delivers more torque giving faster acceleration and more pull on steeper gradients whilst maximising overall range.

Mountain bikes get more torque still, offering explosive fast acceleration and very powerful pull for use in the most demanding surroundings, offering a more thrilling fast paced experience. These high torque units are generally smaller giving better ground clearance and allowing for shorter chainstays which in turn increase manoeuvrability.

It is worth noting that many manufacturers are increasingly using the higher powered units across a broader cross section of models with the assumption that the rider will use their power controller to select their preferred level of assistance. There is not a clear right or wrong when it comes to the level of power delivery. Personal preference is key here, so obtaining some guidance at the point of purchase is recommended.


As battery technology proceeds to gallop forwards we are moving away from the heavy lead acid units of old, instead harnessing power from lithium ion units (the same battery that your laptop or smartphone uses). Li-ion powerpacks have revolutionised e-bikes, reliability has increased hugely, weight has dropped noticeably and overall range has leapt forwards. This ever increasing range has pulled e-bikes out of the territory of short distance commuters and shopping bikes and into the reaches of serious cyclists and long distance riders. Not long ago many high end models could only achieve 10 to 15 miles at best, you can now hop aboard a quality e-bike and depending how hard you ask it to work you can get anything between 20 and 100 miles.

Another benefit of modern battery technology is the relative speed of charging times. What was once a 12 hour affair can now be achieved in as little as 3 ½ hours. What is better still is that units can if needed, be topped up (as opposed to being fully charged and discharged). As little as half an hours charge could get you 7 or 8 miles at high power making it far easier to extend your mileage whilst out on a long ride if you take your charger along for the ride and find a friendly café etc.

Quality batteries typically vary between 300 and 500 wh. And produce 36 volts.

You can expect a quality e-bike battery to last up to 10 years if looked after properly.


The handlebar mounted control unit gives access to the features and functionality of the e-bike. There are several styles of controller varying from basic economy units which employ simple switches and led lights to indicate battery charge levels.

Digital units incorporate an lcd display which have multiple functions such as battery capacity, a precise range guide, a feature which shows how hard the motor is working, along with standard bicycle computer functions such as speed, average speed, time, odometer etc. Gps units are available at higher pricen points.

The controller is actuated by a thumb switch which raises or lowers the power level whilst simultaneously displaying the achievable mileage within each level of assistance. Ultimately the less you ask the motor to help the further it will take you. This function makes it very easy to monitor your power drain whilst maximising your desired range.

Most e-bikes now have a walk mode which can be activated whilst pushing your bike. Assistance is given up to 6mph which makes moving the cycle a whole lot easier, especially when weighed down with heavy luggage.

Diagnostic mode is present on premium models allowing a specialist dealer to quickly check the condition of your e-bike as well as monitoring battery condition, miles ridden, modes used etc , this makes troubleshooting far simpler. The statistics can be saved and stored as a log for future reference. In addition a name can be assigned to the bike meaning it can be identified if it is ever stolen and recovered. Select models carry a micro usb port, this can be used to charge smartphones and other small digital devices.