The Evolution Of Bikes: Adding Electric Wheels

Electric bicycles are a great way to commute, but they can be expensive. A more affordable option is to convert your existing bicycle into an electric one by adding an electric wheel. This can be done by purchasing an electric bike conversion kit, which typically includes a motorized hub, a controller, and a battery pack. These kits are available in different wattages and motor positions, such as front-hub, mid-drive, or rear-hub, each with its own advantages and disadvantages in terms of weight distribution, ease of installation, traction, and maintenance. The installation process is fairly simple and similar to changing a flat tire, but it's important to consider the compatibility of the kit with your bicycle's wheel size and frame.

Characteristics and Values Table for Adding Electric Wheels to Bikes

Choosing the right electric bike kit

Electric bike conversion kits are a fraction of the price of an e-bike and can be a great way to upgrade your existing bike. There are a few things to consider when choosing the right kit for your needs.

Firstly, you should assess the type of bike you have and how you intend to use it. For example, a mountain bike has a more aggressive riding position than a city bike, so you may want to consider a conversion kit that allows you to feel comfortable and safe when riding. You should also consider the laws, restrictions, and registration requirements in your area, as some states consider e-bikes the same as mopeds or scooters, which may impact where you can ride and what safety equipment you need to use.

Secondly, it is important to know the fitment details of your bike, as conversion kits are often designed for specific wheel sizes and frame types. For example, the Bafang Front Hub Motor kit allows you to choose your wheel size and display preference, as well as the battery size and shape, but it may be a more complex installation process. You should also consider the weight of the kit, as adding weight to the front wheel can make the bike harder to steer, and the extra weight overall will put more stress on the brakes. A bike with an aluminium frame offers a good balance between weight and durability, but you may want to opt for a carbon frame if weight is a priority for you.

Finally, you should consider the power and range of the conversion kit. While smaller motors can fit discreetly inside a wheel hub, larger and more powerful motors will be more visible but offer greater range and more powerful acceleration. You should also consider how many miles you would like to be able to ride between battery charges.

Front hub vs rear hub

When converting your traditional bike to an electric bike, you can choose to add the electric wheel to the front or the rear of the bike. There are several factors to consider when deciding between a front or rear hub motor.

Firstly, weight distribution is important. Most batteries are mounted in the middle or rear of an e-bike, so a front hub motor can help to spread the weight forward and improve overall weight distribution. However, a front-mounted motor will make the front wheel heavier and may make the bike harder to steer. On the other hand, a rear hub motor can provide better traction and smoother acceleration, especially when climbing uphill off-road.

Secondly, consider the ease of installation and maintenance. Front hub motors are generally easier to install, and you can choose from more drivetrain options, such as an internal gear hub, 1X gearing, or belt drive. However, rear hub motors are often more durable and long-lasting due to the stronger frame at the rear of the bike.

Thirdly, think about the visibility and aesthetics of the motor. Many small hub motors are nearly invisible, disappearing behind the gears of a rear wheel and giving the bike a stealthier look. Front hub motors are more visible and can be a dead giveaway of the bike's electric assistance.

Finally, evaluate the compatibility with your bike's existing components. If you have a newer mountain bike, for example, you'll need to ensure the wheel size of the conversion kit matches your bike's wheel size.

In conclusion, both front and rear hub motors have their advantages and disadvantages. While front hub motors offer improved weight distribution and easier installation, rear hub motors provide better traction, smoother acceleration, and a stealthier appearance. Ultimately, the decision depends on your personal preferences and the specific characteristics of your bike.

Weight distribution

The weight of an electric bike is influenced by several factors, including the battery, motor, frame, and accessories. The battery is often one of the heaviest components, weighing between 2 and 4 kg. The motor power also impacts the weight, with higher power motors weighing more. Other components such as the frame material, suspension systems, braking systems, and wheel size can also add to the overall weight of the bike.

When adding an electric wheel, consider the position of the battery and motor. A mid-drive motor mounted at the bottom bracket can help maintain the bike's centre of gravity and improve handling. A lower centre of gravity can also improve aerodynamics and enhance stability, especially when turning or dealing with rough terrain. The battery is typically mounted on the rear rack, down tube, or under the seat, with a lower position helping to maintain balance.

The type of frame material can also affect weight distribution. Steel frames are sturdy but heavy, adding up to 5 kg to the weight of the bike. Aluminium frames are lighter, typically weighing between 1 and 3 kg, and offer a good balance between weight and durability. Carbon fibre frames are the lightest option but may not be as strong.

When converting a traditional bike to an electric bike, consider the weight distribution of the new setup. The heavier the bike, the more effort is required from the motor to maintain speed and climb inclines, which can reduce the range and efficiency of the bike. Proper weight distribution with a well-balanced centre of gravity can enhance the stability and comfort of the ride, making it feel more natural.

Installation process

The installation process for an electric wheel on a bike is fairly simple and can be completed in a couple of hours. The first step is to choose the right electric bike kit for your specific needs, considering factors such as wattage, motor position, wheel size, and whether you want a front-wheel or rear-wheel drive.

Once you have selected the appropriate kit, the next steps will depend on the type of kit you have chosen. If you have chosen a front-wheel drive kit, you will need to remove your old front bicycle wheel and transfer the tire and inner tube to the electric hub motor wheel. This type of kit typically includes a controller, a motorized front wheel, and a tire, but you may need to purchase a battery separately.

For a rear-wheel drive kit, the process is similar, but you will be removing the rear wheel instead. Some kits may also require you to attach a 'stud' to the chainstay to hold the unit in place and loop a pedal sensor to the crank arm.

After installing the new wheel, you will need to bolt the speed controller onto the frame and add the throttle to the handlebars. The kit should come with compatible plugs to make these connections easy. The trickiest part of the conversion can be connecting the battery to the speed controller, as they may not have matching connectors if they were purchased from different vendors. In this case, you may need to change the wire connector on one or both components, which can be done with a soldering iron.

Finally, you will need to consider the placement of any displays, gauges, or other accessories that come with your kit.

Connecting the battery

To connect the battery of your electric bike conversion kit, you must first locate the controller, which is the "brain" of the bike. This is generally installed on the frame, under the seat, or next to the battery box. It manages the signalling between the battery, motor, pedal-assist system, and other electronic components.

Before you start connecting the controller, gather the necessary tools and equipment, such as a Phillips screwdriver or hex wrench, electrical tape or heat shrink tubing, wire cutters, and cable ties. Check that all connection points are prepared and ready. Ensure the battery power is completely disconnected to avoid the risk of a short circuit or electric shock.

The battery wires are usually the two thickest wires on the controller, divided into positive (red) and negative (black). Pay close attention to polarity when connecting these wires. First, connect the red wire to the red terminal, then the black wire to the black terminal, ensuring a tight connection. You can then wrap the connector with electrical tape for added protection against short circuits.

After completing all the wiring connections, thoroughly test the electric bike. Check that each cable is firmly connected and in the correct position, especially the battery and motor cables. Reconnect the power supply and test the throttle and brake. Turn the throttle to ensure the motor accelerates smoothly, and gently press the brake to check that the motor stops promptly. If your bicycle has a pedal-assist system (PAS), gently step on the pedal to verify that the motor correctly receives the auxiliary signal.

Frequently asked questions