Why Your Hub Motor E-bike Isn’t Hitting Its Top Speed (And How to Fix It)

There’s nothing like the thrill of an e-bike at full speed, but it can be frustrating when a hub motor won’t reach its usual top speed. Though reliable and simple, hub motors can still develop issues that limit performance. This guide breaks down common causes of power loss, from sensor tweaks to internal motor checks and speed limiters, and explains how to get your e-bike running at its best again.

Common Causes & Quick Fixes

This section details the most frequent and often straightforward issues that can prevent an e-bike from achieving its maximum speed.

Speed Sensor & Magnet Issues

The speed sensor, typically situated near the rear wheel or crank arm, operates in conjunction with a small magnet affixed to a wheel spoke or the crank to measure rotational movement. This measurement is critical for the controller to accurately determine speed and modulate assistance.

When these components accumulate dirt, become misaligned, or suffer damage, the e-bike may display erroneous speeds, deliver inconsistent power, or even cease to function correctly. It has been observed that approximately 40% of reported speed problems are directly attributable to misalignment or accumulated debris on the sensor and magnet.   

Symptoms of these issues include erratic speed readings on the display, inconsistent power delivery (where the motor cuts in and out), or a complete loss of power. Furthermore, the e-bike's display might present specific error codes, such as E21, 014, W011, or 503, which frequently indicate speed sensor malfunctions.   

To address these problems, first, a visual inspection is crucial: locate the speed sensor, commonly found near the rear wheel spokes, and its corresponding magnet. Examine both for any accumulation of dirt, mud, or debris, and for any signs of physical damage. Thoroughly clean both components to ensure optimal performance.

Second, proper alignment is paramount. Ensure the sensor is correctly aligned with the magnet, maintaining a minimal gap, typically around 1mm. If the sensor has shifted, gently adjust its position until it achieves proper alignment. Lastly, some e-bike models offer speed sensor calibration through their display settings. This process may involve an "auto" calculation of wheel size or require manual input of the wheel circumference to enhance accuracy.   

Speed sensor issues are common, often caused by dirt and moisture — simple factors that many riders overlook. Regular cleaning and basic visual checks aren’t just good practice; they’re crucial for preventing speed problems and avoiding unnecessary repairs. By making routine cleaning and sensor alignment part of regular maintenance, riders can solve many performance issues early with minimal effort.

Wiring & Connection Problems

The intricate network of wires and connectors within an e-bike is responsible for transmitting essential signals and power among all its components. Loose, damaged, or corroded wires can disrupt these critical electrical pathways, resulting in erratic speed, inconsistent power delivery, or even a complete loss of functionality. Data indicates that approximately 30% of the speed-related issues encountered by technicians are attributable to faulty wiring.   

Symptoms of wiring and connection problems include inconsistent throttle response, jerky movements of the e-bike, incorrect speed readings on the display, or the display becoming entirely unresponsive. Riders might also observe flickering lights or intermittent power supply.   

To address these issues, a meticulous visual inspection of all wire connections throughout the e-bike is recommended. Look for any signs of wear, such as cuts, kinks, fraying, or exposed insulation.

Particular attention should be paid to the connections leading to the controller, motor, battery, and all sensors. It is crucial to ensure that all plugs are fully seated and that connections are firm and tight. A common troubleshooting technique involves unplugging and then firmly re-plugging each connection to ensure a proper fit.

Additionally, inspect for any green or white buildup (corrosion) on the metal contacts within connectors. These dirty or corroded connections should be cleaned using a specialized electrical contact cleaner and a soft brush. If wires are found to be severely damaged, frayed, or completely broken, they may require repair (e.g., by splicing and insulating) or complete replacement.   

Wiring issues are a common cause of e-bike speed problems. Vibration and weather can loosen connections, cause corrosion, and disrupt power or signals. Since wiring is especially vulnerable, good cable management and regular checks are essential. Securing cables properly and inspecting connections help prevent failures and keep the bike running reliably.

Recommended: Common Electric Bike Wiring Problems & Troubleshooting Tips

Battery Health & Power Delivery

The e-bike's battery serves as the core of its electrical system. A weak, insufficiently charged, or aging battery simply cannot consistently provide the adequate power required for the motor to operate smoothly or achieve its intended top speed. Battery-related issues account for approximately 10% of speed problems.

This often manifests as "voltage sag"—a temporary, yet discernible, drop in the battery's voltage during periods of high power demand, such as rapid acceleration, climbing steep hills, or carrying heavy loads. This voltage reduction occurs due to the battery's inherent internal resistance.   

Symptoms include reduced acceleration, a noticeable decrease in top speed, diminished overall performance, and a rapid drop in the battery indicator on the display when under load. If the voltage falls below a critical threshold, the controller may even temporarily cut power to safeguard the battery.   

To address these concerns, it is imperative to ensure the battery is always fully charged before commencing a ride. A voltmeter or multimeter should be employed to test the battery's voltage levels.

This test should be performed both when the bike is stationary and while it is under load (e.g., during riding or when spinning the wheel) to identify voltage sag. Readings should be compared against the manufacturer's specifications. All battery connections must be secure, and the battery's pins should be correctly aligned, as misalignment can impede proper power delivery.

To mitigate the effects of voltage sag, riders should endeavor to avoid sudden, intense power demands, particularly when the battery charge is low. Gradual acceleration and maintaining a steady speed can help alleviate strain. When utilizing high Pedal Assist System (PAS) levels or ascending hills, it is advisable to pedal more vigorously or reduce the PAS level to lessen the load on the battery.

If the battery is old, exhibits visible swelling (which represents a serious fire hazard requiring immediate professional intervention ), or consistently experiences overloading despite reduced PAS use, replacement may be necessary.   

Battery issues like low charge and voltage sag are major reasons for reduced e-bike speed. Voltage sag happens naturally but worsens with high power demand or aging batteries. Often, slow speed isn’t a motor fault but a sign the battery can’t keep up.

Riders can help by accelerating gradually, using lower PAS levels, pedaling more, and maintaining good charging habits. Smart riding and proper battery care can boost speed and extend battery life without extra costs.

Controller Glitches & Software

The controller functions as the "brain" of the e-bike, interpreting sensor data and precisely managing the power delivery from the battery to the motor. When the controller malfunctions due to age, software issues, or internal damage, it can lead to inconsistent power output, erratic speeds, or a failure to correctly interpret sensor data. Faulty controllers are implicated in up to 20% of motor issues in advanced e-bike systems.   

Symptoms of controller problems include error codes displayed on the e-bike's screen , inconsistent power delivery (where the motor cuts in and out), erratic speeds, unexpected motor behavior, or even unusual noises emanating from the bike.   

To address these issues, a simple reset of the controller or an update of its firmware/software can sometimes resolve minor glitches and speed problems. Riders should consult their e-bike's user manual for specific instructions on how to perform a reset.

Firmware updates can also enhance torque delivery algorithms and improve thermal limits, thereby boosting overall performance. It is also important to verify that the main power switch is in the "on" position and to check for any blown fuses or tripped circuit breakers, which can interrupt power supply to the controller. All wiring connected to the controller should be inspected to ensure it is secure, free from damage, and properly seated.

If error messages persist despite these troubleshooting efforts, or if internal controller faults (e.g., due to water ingress or physical damage) are suspected, it is advisable to seek professional assistance. 

Quick Diagnostic Checklist: Common Speed Problems & Fixes

Deeper Dives into Speed Reduction

These issues are typically less common or necessitate more specialized troubleshooting, often indicating a more fundamental problem within the e-bike system.

Throttle Malfunctions

The throttle on an e-bike facilitates direct motor engagement, enabling power assistance without the need for pedaling. Should the throttle mechanism or its internal sensor malfunction, it can lead to inconsistent power delivery, a complete failure to engage the motor, or even unintended acceleration or deceleration.   

Symptoms include the throttle feeling stuck in the rearmost position or failing to return smoothly to its original place. Riders might experience inconsistent or jerky power delivery, a lack of power even when the throttle is fully engaged, or the motor unexpectedly speeding up or slowing down while the throttle is held steady. Error messages related to the throttle may also appear on the e-bike's display.   

Initial troubleshooting involves a visual examination of the entire throttle unit. Check for any visible damage such as cracks, loose screws, or frayed or broken wires near the throttle mount. The grip should twist easily and smoothly, without feeling stuck or rough. Accumulation of dirt or grime can sometimes impede its operation; wiping it down with a clean rag may resolve this.

Next, trace the wire extending from the throttle to its connection point, typically the controller. Inspect the entire length of the wire for any cuts, scrapes, or kinks. Pay close attention to the connectors where the wire plugs in, ensuring they are fully seated and that none of the small metal pins inside are bent or broken. Loose connections are common due to riding vibrations; unplugging and then firmly re-plugging them can often resolve the issue.   

For more advanced diagnostics, a multimeter can be employed to identify electrical problems. To check wire continuity, set the multimeter to the "continuity" setting (often indicated by a sound wave or diode symbol).

With the e-bike battery unplugged, place one probe on one end of a throttle wire and the other probe on the opposite end where it connects to the controller. A functional wire should produce a beep or a low numerical reading. This process should be repeated for all throttle wires; if a wire shows no continuity, it is likely broken internally.

To assess the throttle's voltage output, carefully reconnect the e-bike battery and power on the system. Set the multimeter to the DC voltage setting (around 20 volts). Carefully touch the multimeter probes to the power and ground wires at the throttle connector; a reading of approximately 5 volts is typically expected.

Then, place one probe on the signal wire and the other on the ground wire. When the throttle is not engaged, a low voltage (close to zero) should be observed. As the throttle is slowly twisted, this voltage should increase smoothly. If the voltage does not change or fluctuates erratically, the internal sensor of the throttle may be faulty.

If the throttle does not return to its resting position, or if multimeter tests indicate a faulty internal sensor, replacement of the entire throttle unit will likely be necessary.  

Pedal Assist System (PAS) Problems

The Pedal Assist System (PAS) utilizes a sensor (either cadence or torque-based) to detect the rider's pedaling motion, subsequently instructing the motor to provide assistance. If the PAS is not functioning correctly, the motor will fail to assist pedaling efforts, which can significantly reduce the effective top speed and make riding considerably more strenuous, particularly on inclines.   

Symptoms include the pedal assist feeling less effective, inconsistent, or having ceased operation entirely. The e-bike will feel heavier and require greater rider effort to maintain speed.   

To address these issues, locate the magnet ring on the front sprocket or crank arm and the corresponding PAS sensor. Ensure the magnet ring is properly aligned with the sensor. Accumulation of dirt or a shifted magnet can prevent the sensor from accurately detecting pedaling motion. Thoroughly clean both the sensor and magnet with a damp cloth to remove any dirt or debris.

If the magnet ring has been dislodged, it can often be gently adjusted using a flathead screwdriver to move it closer to the sensor. Next, inspect all wires and connections running between the PAS sensor and the motor/controller. Look for any loose, damaged, or corroded wires that could be disrupting the signal. Ensure all connections are properly seated and secure.

While seemingly unrelated, a low battery charge or poor battery connections can sometimes affect PAS functionality, as the system requires adequate power to operate. Ensure the battery is fully charged and securely connected. Some more advanced torque sensors may require calibration to resolve erratic motor behavior. Riders should consult their e-bike's manual for specific calibration steps if applicable.   

Brake Cut-Off Switch Engagement

A crucial safety feature on most e-bikes is the brake cut-off switch. These switches are designed to instantaneously cut motor power when the brake levers are engaged, thereby preventing the motor from operating against the brakes. However, if these switches become misaligned, get stuck, or become overly sensitive, they can cause unintended motor cut-off, leading to a sudden loss of speed or preventing the motor from engaging at all.   

Symptoms include the motor unexpectedly cutting out, especially when the brakes are not actively being applied, inconsistent motor engagement, or specific error codes like "Error 25" appearing on the display. Riders might also observe that the brake levers feel sticky or do not fully return to their resting position.   

To diagnose and fix these issues, first ensure both brake levers fully return to their resting position when released. If a lever is sticky or jammed, it can cause continuous motor cut-off. Lubricate the pivot points if necessary.

Next, visually inspect the small magnet attached to the brake lever and the sensor mounted on the brake body for proper alignment and the correct gap between them. Clean any dirt, mud, or debris that might be interfering with their function. Some brake cut-off switches, particularly from brands like Tektro, offer sensitivity adjustment.

This typically involves loosening a small set screw and then adjusting an adjustment bolt to alter the distance between the sensor and the magnet. Turning the bolt counter-clockwise can decrease sensitivity (motor cuts off later), while turning it clockwise increases sensitivity (motor cuts off sooner). 

For a more definitive diagnosis, it is possible to carefully disconnect both brake cut-off switches from the e-bike's electrical system. After disconnecting, test the bike in a safe, open area for a short ride. If the motor functions normally (PAS/throttle engages, no errors), the problem lies with one of the brake sensors.

The switches can then be reconnected one at a time to pinpoint the specific faulty switch. If adjustment is not possible (as some brands/models lack this feature) or if the switch is physically damaged, replacement of the entire brake lever assembly or switch may be necessary.   

Recommended: Solving E-Bike Brake Cutoff Switch Problems: A Comprehensive Guide

Motor Health: Internal Issues (Hub Motor Specific)

While hub motors are generally robust and require minimal maintenance, internal issues can severely compromise their performance, efficiency, and ultimately, the e-bike's top speed. These problems often arise from prolonged stress or inadequate maintenance.

Overheating

Overheating of the motor can be caused by riding in high ambient temperatures, carrying heavy loads, prolonged ascents on steep hills, or consistently riding at high speeds. The controller may also reach its thermal limit, initiating a shutdown.

Symptoms include the motor casing feeling excessively hot to the touch, a noticeable reduction in power output, or sudden, unexpected shutdowns. Overheating can lead to irreparable damage to motor components. To prevent overheating, it is advisable to limit the carried load, maintain moderate riding speeds, particularly in challenging terrain, and select lower power modes when appropriate.

Allowing regular rest periods during extended rides or demanding routes enables the motor to cool down. Enhancing natural airflow by riding at moderate speeds can assist, and some advanced users might consider accessories such as cooling fans or heat sinks. Monitoring motor temperature via Bluetooth diagnostic tools can also aid in managing power output.   

Bearing Failure

Hub motors rely on internal bearings for smooth rotation, which can wear out over time due to heavy use, loss of lubrication, or becoming rusted or damaged. Improper alignment or excessive vibration can also contribute to bearing degradation.

Symptoms include loud grinding, clicking, or a high-pitched whine emanating from the motor. Riders might also detect roughness or excessive play/wobble when spinning the wheel by hand. A healthy bearing should operate almost silently and smoothly.

If bearing issues are suspected, the motor casing will need to be opened to inspect, lubricate, or replace the bearings. This is a more advanced DIY task. Prior to internal inspection, ensure all external fasteners (axle nuts, spokes) are tight, as loose components can mimic bearing noise.   

Hall Sensor Issues (Internal)

Hall sensors are small electronic components situated inside the hub motor that detect its precise rotational position. This information is crucial for the controller to smoothly commutate (switch current to) the motor windings.

If these sensors become dislocated, damaged, or fail (often due to overheating or vibration), the controller receives incorrect or no information. Symptoms include the motor juddering, stuttering, or exhibiting jerky acceleration, especially from a standstill. There might be no spin at all, or even reverse rotation.

Specific error codes such as E07, 007, 08, 09, 23, or 24 frequently indicate Hall sensor problems. To diagnose, inspect the wiring for the Hall sensors for any damage or loose connections. A multimeter can be used to test the voltage switching on the signal wires as the wheel is slowly rotated.

If a sensor is faulty (e.g., a constant 0V or 5V reading), replacement is necessary. This is a complex DIY task that typically requires motor disassembly and often soldering.   

Winding Damage

The copper windings inside the motor can degrade or become damaged due to excessive current flow (overcurrent), prolonged overheating, moisture ingress, or severe vibration. This leads to reduced efficiency and can cause short circuits or open circuits within the motor.

Symptoms include reduced power output, the motor not spinning smoothly, or unusual grinding/scraping noises. A multimeter can be used to measure the resistance between each of the motor's phase wires. All three pairs should exhibit a similar, low resistance.

If one pair measures significantly higher, or shows an open circuit (infinite resistance), it indicates damaged windings. Repairing motor windings is generally a highly specialized and difficult task, often necessitating professional intervention or motor replacement.   

Internal motor issues such as overheating, bearing failure, Hall sensor failure, and winding damage can severely restrict top speed and lead to expensive repairs. Overheating is not merely a symptom but a direct cause of deeper internal motor damage, which can lead to Hall sensor failure and winding degradation. This means that a seemingly simple issue like riding too strenuously or in hot weather can cascade into multiple, more complex internal motor problems.

Furthermore, the motor's internal Hall sensors are distinct from the external speed sensor, introducing a layer of complexity in diagnostics where a "speed sensor error" on the display might refer to either the external wheel sensor or the internal motor Hall sensors, depending on the specific error code.

Addressing overheating through rider behavior adjustments (e.g., selecting lower power modes, incorporating rest periods) and diligent maintenance (e.g., keeping the motor housing clean for optimal cooling) is critical preventative maintenance for the entire motor system. This approach not only prevents immediate shutdowns but also safeguards against long-term, costly internal damage.

This emphasizes the importance of thermal management for both motor longevity and sustained performance. It also clarifies a potential diagnostic ambiguity by differentiating between the external speed sensor (which provides speed data for display and limiter enforcement) and the internal Hall sensors (which are vital for the motor's smooth commutation and operation), guiding the user to consider both when troubleshooting "sensor" issues.

Drivetrain Efficiency: Chain & Gears

Even on e-bikes equipped with powerful motors, a well-maintained and efficiently operating drivetrain—comprising the chain, cassette, chainring, and derailleur—is fundamental for effectively translating both human pedaling power and motor assistance into forward motion. A compromised drivetrain can significantly reduce the effective top speed and overall efficiency.   

Chain Tension & Wear

A chain that is excessively loose or worn can skip under load, derail from the gears, or lead to inefficient power delivery. The increased torque generated by an e-bike motor places higher demands on the chain, accelerating its wear compared to traditional bicycles.

Symptoms include the chain making contact with the bike frame, the chain dropping or skipping gears, difficulty in pedaling smoothly, or a noticeable reduction in the power transferred to the wheel.

To rectify this, regularly check and adjust chain tension. For single-gear bikes, this typically involves loosening the rear axle nuts and carefully pulling the rear wheel backward until the chain exhibits approximately half an inch of vertical play. For multi-gear bikes, adjustment may involve the B-tension screw on the rear derailleur or utilizing the rear wheel adjustment.

A chain wear indicator tool should be used to check for chain elongation, and worn chains should be replaced promptly. Replacing chains before they are excessively worn prevents damage to more expensive components such as cassettes and chainrings.   

Dirty/Damaged Gears (Cassette & Chainring)

The accumulation of dirt, grime, and debris on the cassette cogs and chainring teeth can increase friction and diminish the efficiency of power transfer. Damaged or worn-out teeth can also lead to skipping and poor performance.

Symptoms include difficulty pedaling, a noisy drivetrain (e.g., grinding or clunking sounds), or the visual observation of "shark fin" shaped teeth on the cassette or chainring, which indicate significant wear.

To address this, clean gears regularly using a degreaser and a stiff brush. If teeth are visibly damaged or excessively worn, replacement of the affected components will be necessary.  

Gear Ratio Impact

The selected gear ratio directly influences the balance between torque (for climbing and acceleration) and speed (for cruising on flats). A higher gear ratio facilitates higher speeds on flat terrain, as each pedal stroke covers greater distance. Utilizing the optimal gear for the terrain and desired speed helps maintain e-bike drivetrain efficiency and extends battery range.

Symptoms include "pedaling air" (spinning pedals too rapidly without a corresponding increase in speed) at high speeds, the motor straining excessively on inclines, or a noticeable reduction in battery range.

To optimize, riders should learn to shift appropriately for the terrain and their desired speed. Understanding the trade-off is key: employ a lower gear for climbing hills or starting from a stop to maximize torque, and shift to a higher gear for cruising on flats to achieve greater speeds. This practice ensures both human pedaling and motor operation remain within their most efficient ranges.  

External Factors Affecting Your Top Speed

These factors are not malfunctions of the e-bike's components but can significantly reduce perceived top speed and overall performance.

Tire Pressure

Tire pressure is a critical determinant of an e-bike's performance, safety, and overall riding experience. It directly influences rolling resistance, which, in turn, impacts the e-bike's efficiency, speed, and battery consumption.

Underinflated tires increase rolling resistance, compelling the motor to exert more effort and consume additional power, which shortens battery life and reduces overall riding distance. Conversely, excessively high pressure can lead to diminished grip and reduced comfort.   

Symptoms of incorrect tire pressure include a sluggish or "draggy" ride, reduced top speed, faster-than-usual battery drain, and an elevated risk of punctures.   

To optimize tire pressure, always begin by consulting the manufacturer's recommended pressure, typically printed on the tire sidewall or found in the bike's manual. This provides a baseline range. Fine-tune tire pressure based on several factors:   

Rider Weight & Cargo: Heavier riders or those transporting additional cargo necessitate slightly higher pressure for stability and to prevent excessive tire deformation.   

Terrain: For smooth pavement, higher PSI reduces rolling resistance and enhances speed. For rougher terrain (e.g., gravel, dirt), slightly lower PSI improves traction and shock absorption.   

Weather Conditions: Temperature fluctuations affect tire pressure (cold temperatures decrease it, while heat increases it ). In colder weather, slightly lowering PSI can improve grip, whereas in warmer weather, higher pressure boosts efficiency.   

Regularly checking tire pressure, ideally on a weekly basis, is a crucial part of e-bike maintenance. This practice helps maintain an optimal balance among comfort, performance, and safety.

Rider & Cargo Weight

The total weight of the rider and any cargo directly affects an e-bike’s speed and range. Heavier loads require more motor power, draining the battery faster and lowering efficiency, especially when climbing hills or accelerating. Symptoms include slower acceleration, lower top speed, and shorter range.

To counter this, riders can use lower assist levels, pedal more, keep tires properly inflated, and choose a larger-capacity battery if needed. Smooth, consistent pedaling also helps the motor run more efficiently. Extra weight doesn’t mean something is broken — it naturally increases strain on the system, so adjusting riding habits can help maintain speed and range.

Environmental Conditions (Wind, Temperature, Terrain)

External conditions can significantly affect an e-bike’s top speed. Strong headwinds create drag, slowing the bike and draining the battery faster — a more aerodynamic riding position and fitted clothing help reduce resistance.

Extreme temperatures also impact battery performance: cold weather can cut range, while high heat can damage the battery or motor. Keeping the battery warm in winter and shaded in summer helps maintain performance. 

Finally, rough terrain or steep hills put extra demand on the motor and battery, lowering speed and range. Shifting gears properly and using lower power modes when needed can conserve energy and protect the system. Recognizing how weather and terrain affect speed helps riders adjust their style to get the best performance in any conditions.

Speed Limiters: Understanding and Adjustment

Most electric bikes are manufactured with a governor system that restricts their top speed to comply with legal limits, typically ranging from 20 mph to 28 mph in many regions. These limits ensure that the e-bike can be ridden legally on public roads and paths.

It is crucial to understand that removing or adjusting these speed limiters can have significant legal implications, potentially reclassifying the e-bike as a motor vehicle and requiring registration, insurance, or a license, depending on local laws.   

How Speed Limiters Work

Most modern e-bikes employ an electronic controller that governs the motor's performance, including speed limits. The e-bike's computer uses information from the speed sensor to determine when to reduce power, automatically slowing down the motor as the predefined speed limit is approached. This process happens instantaneously to maintain legal compliance.   

Methods for Adjustment/Removal

Several methods exist for adjusting or removing speed limiters, though not all are applicable to every e-bike model, and some require advanced technical knowledge:

Adjusting Controller Settings: Many e-bikes allow for direct adjustment of speed limits through their onboard display or controller settings menu. This often involves navigating to a specific setting (e.g., "speed limit" or "motor power") and adjusting the maximum speed.   

Speed Limiter Removal Devices: Aftermarket devices, often referred to as "tuning modules" or "dongles," can be installed between the bike's controller and battery to bypass speed restrictions. These devices trick the controller into believing the bike is moving slower than its actual speed.   

Modifying Motor Wiring: Some e-bikes may have a physical speed limiter wire connected to the motor's controller that can be cut or disconnected. This method is generally not recommended for beginners due to its complexity and the risk of damaging other wiring.   

Firmware/Software Updates: For e-bikes with digital controllers, modifying the firmware or software can remove speed limits. This often involves connecting the controller to a computer and using specialized software to adjust settings. However, performing software updates after unlocking a custom speed limit can make it difficult or impossible to revert the modification.   

Adjusting Battery Settings: In some systems, adjusting the Battery Management System (BMS) settings to increase voltage or output can boost power and potentially raise the bike's speed limit. The BMS also has current limiting functions that can prevent excessive current flow, which might indirectly affect perceived speed if the system is being overloaded.   

Replacing the Controller: Installing a more powerful, compatible controller can increase speed capabilities beyond the stock limitations.   

Adjusting Pedal Assist System (PAS) Settings: Modifying or disabling the PAS can remove speed caps imposed by the system, allowing the bike to run on full electric power.  

Using E-Bike Adjustment Apps: Some manufacturers provide smartphone applications that allow users to tweak speed or power settings directly from their phone.   

It is important to note that removing the speed limit does not inherently provide additional power to the motor; rather, it allows the motor to sustain its power output beyond the manufacturer's set speed threshold.

However, operating an e-bike above its intended speed can increase wear on the motor and battery, potentially void warranties, and may affect the bike's balance and braking performance at higher speeds. 

Conclusion

An e-bike’s top speed depends on more than just motor power, it’s shaped by the whole system: controller, sensors, battery, wiring, and even rider habits. Many speed issues come from simple problems like dirty sensors, loose wires, or voltage sag, not major failures. External factors like extra weight, low tire pressure, wind, temperature, and hills also play a big role. Regular cleaning, checking connections, caring for the battery, and adjusting riding style help prevent slowdowns. For serious issues, professional help is best to keep your e-bike running safely and at its best.

Conclusion

Why isn't my e-bike reaching its top speed?

Many factors can limit your e-bike's top speed, including low tire pressure, a low battery charge, a misconfigured speed limiter, issues with the motor or controller, or even external factors like heavy loads or headwinds.

How can I increase my e-bike's speed?

Check your tire pressure, ensure your battery is fully charged, inspect for brake drag, verify speed limiter settings on your display or controller, and consider optimizing your riding style and cargo weight. For electrical issues, consult your e-bike's manual or a professional.

Is it legal to remove the speed limiter on my e-bike?

Removing or modifying an e-bike's speed limiter can be illegal and may void your warranty. E-bike classifications are based on factory-set speed limits, and exceeding them can reclassify your bike, subjecting it to different regulations. Always check local laws before making modifications.