Everything you need to know before you buy an e-bike
So, you're interested in an electric bike? Great! The humble bicycle has been with us since 1817, when German Baron Karl von Drais invented his Laufmaschine, supposedly as an alternative to using horses to get around.

However, electric technology is rapidly evolving and e-bikes are becoming an increasingly common sight on our roads, helping to reconnect people with cycling and cleaner, healthier transport.

Here, we've put together our definitive guide aimed at demystifying the basics of e-bikes and what to consider when thinking about investing in one.

Ready to get started? Let's get started.


How does an electric bike work?
An electric bike, also known as a pedal bike, is like a regular pedal bike but fitted with an electric motor and battery to provide assistance, reduce effort and in many cases make your journey faster.

The key word here is "assistance". Unlike an electric motorbike, which works by engaging the throttle after the initial start, an electric bike provides powered pedal assistance to supplement your effort on each pedal stroke. This is where the term 'electric assist' comes from.

In the UK, electric bicycles are subject to strict legislation. The bike must be powered by pedals and the motor can provide up to 250 watts of additional assistance at a maximum speed of 25 km/h (15.5 mph), after which it cuts out. To put this in perspective, this is about the same amount of power that a trained club cyclist can produce by working hard for an hour on his legs alone.
Types of electric bicycles
The popularity of electric bicycles has grown rapidly in recent years. Whereas once upon a time the only bikes you could find with electric assistance were city bikes, now the market for electric assisted bikes is diversifying.

All kinds of cyclists have started using electric bikes, including mountain bikers and road cyclists who prefer to have a little help along the way. As a result, there are electric road, electric mountain and electric gravel bikes, where the motor and battery are designed to look like the frame of a traditional enthusiast bike, as well as bikes designed for urban environments.

These 'urban' or 'hybrid' e-bikes can be equipped with either standard or straddle frames (so-called 'straddle bikes' because of their submerged top tubes) - or no top tube at all - to make boarding easier). These can also be equipped with large luggage boxes and are known separately as "cargo e-bikes". They both have flat handlebars and an easy seating position compared to enthusiast bikes and e-bikes.

However, it is worth noting that the popular term for these bikes - 'urban bikes' - is actually a bit of a misnomer. These bikes are equally capable of being ridden between the country's rural towns, as they are used for commuting or to shops in built-up areas.

Another option is the folding e-bike pioneered by brands such as Brompton. These offer a motor system specifically designed to fit in a smaller, lighter frame, and while they are often less powerful, they offer a great option for those who need to carry their e-bike with them on public transport, wish to store it at their desk below for work, or leave home neatly.

Essentially, in most cases the type of e-bike that is right for you will depend very much on what you intend to use it for.

Motor types - frames and hubs
E-bike motors come in two main forms - mounted in the central structure of the frame (known as the bottom bracket area around which the pedals and crank arms rotate), or in the hub of one wheel. There is no clear winner as to which is the best - instead, each has its own positives and negatives - but both do a good job.

The central or frame-mounted motor directly measures how hard you pedal with each pedal stroke. It can therefore provide a certain amount of extra help depending on the effort you put in and the help settings you choose (more on this later in "Modes").

The disadvantage is that they may require more maintenance than hub motor systems because of the extra pressure exerted through the drive train, especially for very high-powered models.

Hub motors mounted on the rear wheels transfer your efforts to the rear wheels through pedal action, with sensors detecting your inputs and providing assistance. These types of motors are particularly popular on electric road bikes and stylish urban e-bikes due to their low weight and slim design.

Rear hub motors can also be designed into e-bikes at a much lower cost, as the centre section of the bike frame does not need to be designed around it as much as a frame mounted motor. This usually results in lower manufacturing costs and therefore better value for the rider.

In addition, the rear structure of the bike frame is usually the strongest, and most of the rider's weight is pushed down through the rear wheel, increasing traction, which can be beneficial in wetter conditions.

View the ESWINGSPORTS powered by a rear hub motor now

The front hub motors differ in that they are not directly connected to the pedal drive train, but rely on a 'push' to activate and add their own assistance. This sometimes gives the impression that they are pulling the bike while you are pedalling.

These motors are more common on cheaper e-bikes.

Batteries
Battery technology is evolving rapidly and over the last few years some manufacturers have managed to reduce the size of the battery so that it fits into the frame itself, or clips into a cavity within the frame. At the same time, other companies are squeezing more and more power out of tried and tested external battery designs.

Battery size depends very much on its use - for enthusiasts such as mountain bikers and road cyclists, smaller batteries that are fully or partially integrated into the frame are often required for performance and aesthetic reasons. Arguably, urban commuters can be better served by a more practical, larger design that is attached outside the frame or, often, to a custom-made luggage rack (these are also usually cheaper to produce, but do not compromise on quality).

The ability to remove the battery also makes charging easier and more convenient and improves the safety of your e-bike when parked.

You may see variations on this theme, but battery capacity and charging speed should be the primary considerations. If you need to complete longer journeys, or you know you will be more reliant on pedal assistance due to living in a hilly area, using a higher capacity or fast charging battery (or an e-bike) pack that offers replaceable or extendable batteries) will appeal.

Battery capacity is usually measured in amp hours, the higher the number the greater the capacity and potential range.

Note: Battery capacity can be depleted over time and with use and very cold conditions (although the lithium-ion battery technology on which the vast majority of e-bike batteries are based is constantly improving to mitigate this). Look for batteries from reputable companies that offer a warranty.

The motor and battery system work in combination. Well-known manufacturers from the bicycle and electronics industries share this market, sometimes collaborating to develop new systems. These include the specialist Shimano, Ebikemotion and Fazua, as well as more mainstream brands such as Bosch, Sony and Yamaha. Keep in mind that electronic devices and electronic components with built-in frame mounts are rarely cross-compatible, so once you've chosen an e-bike, you need to stick with your system.