I am Looking for an Electric Bike Conversion Kit. What Type Should I Get?
When you are shopping for an electric bike conversion kit you must first think about what you will use it for. Here are some questions to think about to help you decide on the kit that suits you best.
- What distance are will you be riding each day?
- Is the terrain mostly flat or is it hilly?
- How much are you willing to spend?
- How much extra weight would want to add to your bike?
- Do you want it to be light and comfortably powered so that you can relax and enjoy the ride, but also easily transition back to a ride without the motor?
- Do you want a lengthy and time-consuming assembly time requiring lots of tinkering and customization with your electric bike kit, or would you prefer to just throw it together quickly and ride?
- Do you want to use the bike like a motorbike, with no pedalling and fast speeds?
The Four main Types of Electric Bike Conversion Kits
Front in Hub Motor
- No hassles
- Easy installation
- Suitable for most bikes
- Places weight in the front giving good balance
- Simulates an all wheel drive (rear pedals, front motor)
Rear Hub Motor
- A bit more difficult to install with the gears etc
- Improved traction for riding up hills
- The power from the rear wheel makes for a better feel
- The rear wheel can begin to be heavy
Direct to Rear Wheel Geared Drive
In this bike setup the electric motor is bolted to the frame (sits slightly above the rear axle) and a chain runs to the rear wheel
- Tends to be more energy efficient
- Affordable pricing
- Can be a bit bulky and don’t always look the best
- Attaching and assembling properly can be quite fiddly to get it right, and may require extra parts
Pedal Crank Geared Drive
With this setup you bolt the electric motor to near the pedal cranks to the bike frame. The motor drives the cranks after an additional cog is installed to the petal crank cluster.
- Motor powers the gears providing excellent hill capacity and speed
- More efficient when gears are properly used
- Greater wear to the sprockets and chain
- Requires medium to advanced engineering to assemble
- Many parts required
Available Electric Bike Components
Brake Cut out Switch
Breaking is optimised with this feature shutting off power to the motor as you break. It can be necessary on high powered bikes to counter any problems with the throttle sticking on, or at high speed where breaks may not slow the bike enough. It does add another thing to install however so is only really recommended for higher powered electric bikes not so much for the lower powered models.
eBike Regenerative Braking
There is a lot of hype over the energy saving capabilities of regenerative braking, but the reality is it doesn’t weigh up. The energy saving will be better justified by putting the money towards a more aerodynamic design, better batteries, etc. Watch this space though. While the current technology does not make it worth it, there is space in for development in this area ebike braking.
Pedal assist Electric Bike
The advancement of the pedal assist electric bike system that engages and electric motor as you start pedalling has been difficult to miss. It is simple and effective. An issue with this system is when the motor starting is not always required or wanted and also can be draining on the battery. By todays standards the complexity of this system does not provide equal gain.
Electric Bike Batteries
There is a massive market for electric bike battery and gadgets at the moment. With all the other technologies requiring batteries there is huge demand for development in the next ‘best battery’ arena. Some of the main options are:
The light weight and no hassle or maintenance factors that lithium batteries bring to the market cant be overlooked. They are quickly charged and last a long time. Some of the systems are complex and certain varieties require that a battery management system is added to ensure stability and that they are not over charged or drain too quickly (over-discharged). This battery comes in many varieties.
Lithium Polymer Batteries – LiFePo4
Current market trends hold the Lithium Polymer battery as one of the best electric bike batteries. It is maintenance free, holds a lot of power, and it is very light. Some of the better brands claim no significant degrade to performance during the first 2000 cycles. A great advantage is that is can be drained partly or completely without damaging it. This is in contrast to the Lead Acid batteries that can be degraded if they are run completely flat too often, or for example the degrading of NiMH where they are not drained frequently. Those in the market for no maintenance and power to weight cant look past these batteries.
Sealed Lead Acid – SLA
In recent years most electric bikes have used Sealed Lead Acid (SLA) Batteries. They are cheaply produced and require almost no maintenance but are heavy and require a longer charging time. It is likely in coming years newer technology will surpass and replace these batteries as an option.
Nickel Metal Hydride – NiMH
There is no denying the Nickel Metal Hydride batteries are fast charging, less toxic, and weighing less than the SLAs. Energy density is high. The cons are that they require regular full discharges to maximise the batteries life, and performance is reduced in cold weather. These batteries have the edge of SLAs but still are not without some issue.
Electric Motor Types
These motors have been powering electric bikes for quite some time. They come with there drawbacks though. Requiring the occasional servicing they are noisier, heavier and larger than their brushless counterpart. This means that they will likely soon become obsolete. That is not to say they haven’t had a great impact on electric bike evolution with their sturdy hill climbing capabilities and durability.
Brushless DC Motors
These motors are known for being lighter and quieter than brushed motors making them the better option for ebikes. The recent upgrades to this motor on the market include permanent magnet brushless motors, and sensorless brushless motors. It is early days for these new versions but they may develop to become market leaders in the not too distant future.