How to Test an Electric Bike Motor

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Updated March 2, 2023

Troubleshooting and testing your electric bike motor should be your first step when you notice something amiss with your ride. Even if there is nothing wrong, running routine tests on your electric bike’s motor will keep it in premium shape for years to come and help you save money on costly repairs or having to buy a new electric bike. In this article, we’ll run down several steps you can take to test your e-bike motor. Alternatively, if you have other questions like how much an electric bike weighs or how hard you need to pedal an electric bike, we have you covered there as well.

Key Takeaways:

  • Opening your motor may void the warranty on your e-bike, depending on who or where you purchased it. Be cautious when handling wires and electrical components.
  • Loose wiring can have a severe impact on the entire performance of your e-bike. Wear and tear, excess weight put on the tires, or even disuse can weaken the connection to the motor, batteries, throttle, motor controller, and brakes.
  • To be sure that the hall sensor is in sync with the motor, run a voltage test with a multimeter.

Before You Begin

There is no harm in testing your motor to ensure it is in good condition; however, if your bike is under warranty, you could invalidate that warranty by opening up the motor. Speaking of warranty, if you have used something like an ebike speed hack, your warranty is voided as well. Therefore, coverage for your electric bike is just as important.

However, you can learn about bike speed by checking out our article on how fast do electric bikes go.

Additionally, dealing with electric wires and connections could be hazardous to the inexperienced. If you test your electric bike motor and find problems beyond what simple fixes can remedy, please consult your manufacturer or a professional e-bike repair shop. Finally, if you plan to transport your bike with a bike rack, make sure it is compatible with the bike’s battery and motor weight.

Thankfully we have some guides for some easy fixes, like how to repair electric bike throttle, if you would still like to fix a problem that arises yourself.

Test the On and Off Switches

While the usual joked-about ‘tech support’ advice is “have you tried turning it on and off again”, the most common issue that riders face is their e-bike motors not turning on or suddenly switching off. If you’re experiencing this, there might be a problem with your motor controller. To be sure, test it by attempting to power the bike and leave it on for a few minutes. If it does not activate, or if it seems to stutter on and off, then your connection may be weakened or damaged. Routinely checking the on and off functions before you hit the road can alert you to your motor’s overall health.

So, if you’re concerned about buying an ebike, read our Giant Road E-1 Pro review before making a purchase.

Check the Wiring

Inspect the wiring of your electric motor, batteries, and controller. If any of them have come loose, that can foster a weak or faulty connection. If you have already run a few on and off tests, make this your next step. Unplug and inspect connectors for dust, debris, or damage. This is a prevalent issue on e-bike kits that were retrofitted onto standard bicycles by hand. While you’re inspecting the wires, try to sniff them. Overheating within your motor could cause melting, and an easy way to detect it is by searching for the powerful odor of melted plastic or rubber.

Regarding Rear-hub motors

If your e-bike uses a rear-hub motor, you will need to pay special attention to the connecting wires. If you’ve recently hit across some rugged terrain that could have jostled the hardware, or if you’ve been carrying heavy cargo that could put extra weight on the frame, then you should inspect the wires for signs of fraying. Damaged wiring isn’t just detrimental to your bike’s performance, but it can also be potentially dangerous. Fraying isn’t only an issue of rear hub motors, however. All types of motors are susceptible to it, including mid-drives and gear hubs. As e-bikes become increasingly popular, it has created a need for e bike controller settings 36-volt Pro 902 that can help to protect your e-bike from potential damage.

Test the Hall Sensor

Within a hub-style motor are the hall sensors. Hall sensors determine the rotor’s position – the rotor being a wheel of magnets that spins with the stator. This system ensures accurate controller operation. Each hall sensor has three wires and requires a voltage input. Should these sensors fail, the motor controller will not synchronize with the energy sent through the motor. To test the hall sensors, you will need a multimeter device.

A multimeter is a small electric probe, usually with two attached leads, ending in prongs. You’ll use these prongs to test your hall sensor’s voltage by powering the sensor on with a DC battery and applying the prongs to the sensor to generate a readout, which you’ll then compare to the rated voltage included in your manual.

STATS:

  • Failure to start is the most common problem related to e-bikes. (leedsbikes.com)

Sources:

https://www.ebikes.ca/documents/HallSensorTestingFinal.pdf
https://radpowerbikes.zendesk.com/hc/en-us/articles/360046016954-Troubleshoot-a-Bike-that-Won-t-Turn-On#:~:text=A%20low%20charge%20or%20a,to%20turn%20on%20the%20battery
https://www.electricbikecity.com/blogs/learn/how-to-troubleshoot-electric-bike-problems

*https://youtu.be/Yh9ngpOKS5o

*https://youtu.be/Eja88_rkylQ

Troubleshoot and Diagnose an Electric Bike Motor FAQ

Why won’t my electric bike turn on?

If your e-bike isn’t turning on, verify first that the battery is fully charged and in place when you hit the power or mode switch. If your wires are firmly in place, you may need to run a deeper test on the battery itself.

How do I test my eBike’s throttle?

Connect your throttle, motor controller, battery, and a multimeter, and power on the throttle. In voltage mode, the multimeter should clock in at one volt when it is at rest and rise when it’s twisted to full power. This would indicate that it is fully operational.

Can you test an e-bike motor without a controller?

You can test an electric bike motor without a controller in minor ways, such as visually inspecting the wires or as you keep an eye on non-electric components of your bike such as the brakes or wheels. However, you will need a motor controller to run a full diagnostic.
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