How To Select The Right Motor For An Electric Bicycle
Posted on August 30 2017
Are you thinking of converting your bicycle to electric and need help choosing the right motor? Let us help with this quick guide.
Motors can typically be located in three different places on your bike: 1. Front wheel, 2. Rear wheel, or 3. Bottom bracket (Mid-drive motor). The front and rear wheel motors are known as hub motors because they take over the hub of the wheel. The primary advantage of these types of motors (such as our TDCM or Aikema motors) are they are relatively simple and straightforward to do a conversion once you get a wheel built around the motor - just replace your wheel, connect the battery, and you're off! The mid-drive motors (such as our Bafang BBS sets) replace your crank and chain ring through your bottom bracket. The advantages of these motors are they end up taking advantage of your gears and keep the weight distribution low and near the center of your bike.
Voltage and Power
It's easy to get lost in these numbers since everyone will try to sell you on "more performance." But you really need to assess your riding to figure out what you need. First of all, neither of these numbers will necessarily get you faster speed. Top speed is generally capped at 20 or 28 mph depending on the system and this is a government regulation. Lower power motors are perfectly suitable for relatively flat, around town riding and you'll still be able to hit 20 mph or more! More power is best if you're towing a load or are a larger rider. It will also accelerate a little faster and will go faster uphill. Our most powerful motor is a Bafang 48V 1000W BBS-HD system.
A higher voltage motor will allow you to use fewer cells in your battery because the current draw will be less for the same power. As such, it won't run as hot either, which will minimize potential overheating problems. If you don't need to sustain maximum power though, a lower voltage (such as our 36V 500W Bafang BBS) system will work just fine.
We also stock a Bafang 48V 750W BBS-HD motor system. The Bafang HD, for Heavy Duty, motors run more efficiently than their standard BBS counterparts and provide greater maximum torque which is, again, great for accelerating or going up steep inclines.
Of course one of the biggest determining factors in many people's decision to convert to an e-bike is price. Front hub motors like our Aikema kit are generally the least expensive and are great for leisurely rides around the city. They're the easiest to work with since you don't have to deal with the gears and drivetrain at all when doing the conversion.
Rear hub motors like our TDCM kit would be the next step up. These have a freewheel attachment for the rear cogs and provide 500W of power to tackle the odd hill.
The Bafang mid-drive motors are our premium motors but provide access to gears giving more torque assist.