Motor of the Electric Scooter Only Runs At Partial Throttle

Table of Contents

Problem Description

The vehicle only travels at partial throttle and not at full throttle. That is, the maximum speed is not achieved.

User Self-Diagnosis: Causes and Solutions

Causes of Not Reaching Full Speed	Specific Symptoms	Cause Analysis	Resolution Strategies
Battery	Low Battery Charge	When the battery is depleted, your electric scooter may not have enough power to reach its full speed potential.	You need to understand how to regularly charge your electric scooter’s battery to ensure optimal performance.
Battery	Faulty Battery or Charger	If the battery or charger is faulty, it may result in underpowered supply to the scooter’s motor. This can lead to slower acceleration and reduced overall speed.	Have a certified technician perform a comprehensive inspection, repair, or replacement.
Motor	Motor Enters Protection Mode When Overheated	When the motor becomes too hot, it may enter protection mode, limiting its speed to prevent damage.	When you notice your electric scooter overheating, you should take a break.
Motor	Physical Damage or Internal Failure Within the Motor	A damaged motor may not generate enough power, making it difficult for the scooter to reach higher speeds.	Have a certified technician perform a comprehensive inspection, repair, or replacement.
Tires	Underinflated Tires	Lower tire pressure can also reduce the scooter’s efficiency, as the motor has to work harder to turn the tires.	First, you need to confirm the required air pressure. Then, you can use an air pump and the appropriate nozzle to inflate the tire. Insert the nozzle into the tire valve, and use the air pump to inject air into the tire until it reaches the desired pressure. Finally, ensure the nozzle and valve are securely connected, and check that the tire is properly inflated.
Tires	Worn Tread	Tires with poor traction or worn treads can lead to reduced traction, especially on slippery surfaces, which limits the scooter’s speed.	You may want to consider replacing the tires to ensure safety and performance. If you’re unsure how to replace the tires, it’s best to seek professional assistance.
Controller	Faulty or Damaged Wires, Loose or Broken Wires	Wearing out over time or due to external impacts.	Contact after-sales service for professional repairs or replacement of the controller. Ensure all wires in the controller compartment are properly connected and insulated.
Mode	Lower Speed Modes (Such as Eco Mode)	In lower speed modes, the motor output is limited to a lower level, which restricts speed, hill-climbing ability, and acceleration performance.	Check the scooter’s mode settings to ensure it is not inadvertently set to a low-speed mode. Refer to the user manual for different mode options and their corresponding speeds. If you cannot identify or resolve the speed issues, consider taking your scooter to a certified technician for a comprehensive inspection and repair.

Customer Support

If you still have questions, please contact GKB Customer Service service_aftersale@geekbuying.com.

For Engineers

Cause Analysis

When the vehicle travels at partial throttle instead of full throttle, it may be due to an old, worn-out, or faulty battery or battery pack.

The speed controller is connected between the battery and the motor, and most speed controllers have a low-voltage cutoff feature to prevent over-discharge.

When the battery is old, worn out, or faulty, the voltage may temporarily drop to a zero charge state, causing the speed controller to shut off the motor.

This can result in the vehicle operating at partial throttle instead of full throttle.

We can determine the charge state of the battery or battery pack by looking at the voltage levels through a battery charge state chart.

Solutions

Determine Voltage Values	If the vehicle’s dashboard has a battery level display or battery indicator lights, these lights serve as voltage indicators and can help determine the condition of the battery or battery pack. If the indicator lights drop when the throttle is fully engaged and rise when the throttle is at zero or partial, it indicates a significant drop in voltage under load for the battery or battery pack.
Deep Charging	Sometimes, a lead-acid battery pack needs a deep charge to balance the cells and help restore capacity. Try charging the battery pack for 48 to 72 hours and then see if it helps. It’s good practice to perform a few deep charges annually or when significant capacity loss is noticed.
Testing the Battery Charger Port	If the battery charger is plugged into the wall, unplug it. Plug the battery charger into the battery charger port on the vehicle and check if there is an illuminated indicator light on the battery charger. If the indicator light on the battery charger lights up, this means the wiring and wire connectors connected to the charger port are good, and the charger port itself is also good. Not all battery chargers have an indicator light that illuminates when the charger is only plugged into the vehicle, so if the light does not come on, you should perform a secondary voltage test with a multimeter as described below. If you have a multimeter, you can test the voltage at the battery charger port. The voltage level at the charger port should match the voltage level of the battery pack. If the charger port has male terminals, you need to be very careful to avoid shorting the terminals or the charger port housing (if it is metal).
Testing the Battery Charger	Ensure there is voltage at the charger port, then test the voltage of the battery or battery pack to confirm if it needs charging. Plug the battery charger into the charger port on the vehicle and into the wall, then use a digital multimeter to test the voltage of the battery pack. If the voltage rises gradually, it indicates the charger is charging the battery. Continue charging until the indicator light shows a full charge, then test the battery voltage to confirm if it has reached a 100% charged state. If the charger fails to charge to 100%, there may be a fault.
Testing the Battery Pack	Remove the battery pack from the scooter and take out individual batteries to load-test their cells. You can then test each battery using an automotive battery load tester. Most entry-level automotive battery load testers apply a 100-amp load to the battery, which is too high, so a variable carbon pile battery load tester should be used and adjusted to apply a 30-amp load to the battery.
Testing the Battery Pack Voltage	After reading the voltage, you can use the battery charge state chart page to determine the percentage of the charge state. A good battery or battery pack will be at 100% charge state after being discharged and left for a few minutes, or if stored. If the battery pack does not rebound to a 100% charge state within a few minutes after being discharged, it indicates the battery or battery pack is faulty or worn. When a battery pack has been charged to a 100% charge state and its voltage drops below 100% charge state after being left for some time, this indicates the battery pack is faulty or worn. Good batteries and battery packs will recover to a 100% charge state within a few minutes after the vehicle has been driven.