Electric bikes have grown in popularity over the past few years as battery and motor technology has advanced. There are plenty of reasons why an electric bike might be the right choice for you:
- If the sight of a big hill fills you with dread
- If the distance you would have to commute seems a little too far
- You don’t want to arrive at work hot and sweaty
There is a huge range of things you should consider before buying your electric bike from simply the type of bike, to how the bike will help you, and the type of battery.
This brief but thorough guide is to help prompt questions about how your plan on using your bike which in turn make sure the bike you choose is right for you.
Step 1. Plan Your Commute
The first thing to check before you buy your electric bike is the route for your commute. As with bikes in general there are different types of electric bike to suite different terrains and your riding style. We have written a useful post on how to plan your commute here. The factors to take into account for your commute is the terrain, the distance, elevation gain and how long you think it will take you to make the journey. These factors will set how much performance you will want from the electrical drive system on the bike.
STEP 2: Type of Electric Bike
Firstly the type of bike should match the terrain of your commute a road or touring bike for tarmac, mountain bike for off road and cyclocross or hybrid bike for a mixture of the two. Next there are two options of electric assistance, the first and most common type is termed the ‘Pedelec’. This type of electric bike will monitor your pedal strokes and when your pedalling the bike will automatically add some electrical assistance. The ‘some’ will usually vary depending on your speed, pedalling force and pedalling cadence (rpm), the bike effectively knows when to help you and how much.
The second and less common type of electric bike is the ‘twist-n-go’, this type of electric bike where the electrical assistance can be directly switched on and off by you. This is usually done by a switch or a twist grip (usually on the handlebars), this can either be on or off, or with a variable degree of electrical assistance.
Step 3: The Budget
The third step once you’ve weighed up what type of electric bike you want and your commute route is to establish your budget. Your budget is personal to you and your own personal circumstances but its important to do your research so that you get the biggest bag for your buck!
Step 4: The Motor
To provide the electrical assistance the electric must have a motor installed. There are two usual locations for the motor to be housed, these are either somewhere around the bottom bracket or chainset (crank drive) area or inside the hub of one of the bikes wheels (hub motor assist).
The main advantage of the crank drive system is that the assistance is applied at the front of the bikes drivetrain, this means that assistance torque applied to the bike back wheel can be varied by using the bikes gears. This allows crank drive bikes to climb very steep hills. The downside of crank drive bikes is that they are often heavier than the hub motor assist counter parts and are usually only available in the Pedelec style.
Hub motor assist is almost the opposite to the crank drive bikes as the electrical assistance is applied to the wheel independently from the bikes drivetrain, which can mean they struggle with very steep hills. Because of this independence, hub motor bikes can come in either Pedelec or twist-n-go style. Its important to note that there are different types of hub motor, some of them can use internal gearing system to help with hills or they can be direct drive only..
Step 5: The Battery
Electric bikes must also have a battery to power the motor. Battery technology has improved greatly over the past few years to increase the power stored in the battery, reduce the batteries weight and increase the number of charge discharge cycles the battery can withstand. There are a few different options for batteries for electric bikes and as you might expect cost tends to increase with performance.
Lead Acid are quite a dated form of battery chemistry and are certainly the heaviest. They also suffer from quite a low number of battery cycles . You should avoid electric bikes with lead acid batteries.
Nickel Cadmium batteries (NiCad) are an upgrade form Lead Acid but are still quite a dated form of battery chemistry. They are bit lighter than lead acid and have a strong proven track history in portable electrical devices.
An improvement from NiCad batteries are Nickel Metal Hydride (NiMH). NiMH batteries are smaller, lighter and have good good number of charge cycles. Due to their increased power densities they usually store more power than NiCad batteries. NiMH batteries have virtually replaced NiCad batteries for all modern portable electronics.
Lithium Polymer batteries are a modern type of battery chemistry. They are light weight, have a power density and can handle a large number of charge cycles. Lithium Polymer batteries are ideal for for electric bikes and are usually the most common, you should aim to get this type of battery for your electric bike.
Batteries are not without their problems and you should always follow the instructions on how and when to charge use and discharge your battery. Batteries can develop memories, memories for batteries mean that for every time they are charged and discharged they can loose a little bit of their capacity. The amount of capacity the battery can loose varies from how the battery is charged and discharged. but don’t be put off, if you follow the instructions good e-bike batteries should be able of doing around 700 charging cycles before they need to be replaced. Reputable manufacturers generally offer a two year warranty on batteries for electric bikes but you should check what is and isn’t covered.
Step 6: The Equipment and Components
As with conventional bikes, there is a sliding scale for the components your electric bike will be fitted with which. Generally speaking this means the groupset, wheels and finishing kit, to help we have a put together a brief guide on the parts for a bike here. The weight, performance and quality of the components tends to scale with the cost of the bike.
Most bikes are usually built to a price point and electric bikes are no different. You can usually pay a little bit of a premium for the big name brands but they have a few tricks up their sleeve ton where they make cut backs to build the bikes to a price. The groups will usually be from one of the main 2 manufacturers, shimano or sram. Where cut backs are usually made is by the manufacturer fitting own brand or cheaper components for places like the brakes or the chainset, whilst own brand or cheaper components are still good, they might be considered a downgrade over having a full shimano or sram equipped bike.
Second to the frame, the wheels are almost as important for a bike performance. This is due to the fact the wheels are a rotating mass and therefore their weight has much more of an impact on how quickly your bike can accelerate, or decelerate for that matter. Wheels are another area where manufacturers can often make cut backs and use own brand or unbranded wheels, hubs or rims. Again whilst own brand or cheaper components are still good, they might be considered not quite as good as a set of hoops from manufacturers like mavic or fulcrum. But wheels can be a great place for your first upgrade in there future if your bike has a solid spec of other components. However, beware if your electric bike has a hub motor, upgrading your wheels could be more difficult.
On a final point all this research into components and electrics might get you bogged down, but remember the most important thing above all is that your happy with the bike you buy, you enjoy riding it and you get fitter and healthier riding your commute.