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Electric Bike FAQ

Electric Bike Modes: Throttle vs Pedal Assist (Pedelec)

Understanding E-Bike Propulsion Methods and Which is Right for You

Depending on their designation, e-bikes and their motors work in two ways: they can either make your level of pedaling effort easier, or completely take over and simply carry you along for the ride.

When you’re considering which type of e-bike to purchase, it’s important to think about which of these methods the bike offers, the environment(s) you’ll be riding in, and your own abilities and preferences. In this article, the writers here at Electric Bike Report will help you to understand the pros and cons of throttle vs pedal assist electric bikes, and help you to determine which is best for you!

Defining E-Bike Throttle and Pedal Assist Terms

Before we get into the differences between throttle and pedal assist and how they relate to you, let’s define those terms more clearly:

Throttle: a handlebar-mounted device that can engage (and sometimes adjust) power output from the bike’s motor. Electric bikes with throttles can be completely self-propelled, since throttles tell their motors to dispense power without the need for any pedal motion or input from the rider.
Pedal Assist: the standard method of operation for e-bikes. As the term suggests, this method of motor engagement requires the bike’s rider to move the pedals, though depending on the bike’s gearing, type of motor, and type of sensor, the rider may or may not need to actually be engaged with the drivetrain.
Pedelec: This term is a synonym for pedal assist, and is an abbreviation derived from the words “pedal electric cycle.”

It should be noted that, in order to be classified as electric bicycles, all e-bikes must have operable pedals. As such, most e-bikes function through pedal assist, with some having additional throttles – though it is still possible to have a throttle-controlled motor mounted to an otherwise non-electric bicycle with a standard drivetrain.

Aventon Aventure Electric Bike Review OffRoad

Many e-bikes, like the Aventon Aventure 2, offer both throttle and pedal assistance for a range of applications in different environments.

Replacement Electric Bike Batteries Guide

A good e-bike battery should last for hundreds of cycles. With average use, this means several years. Eventually, electric bike batteries need to be replaced as their life cycle comes to an end.

You can tell when a battery is nearing the end of its life when it does not provide you with much range. Some high-quality batteries that come on the top e-bikes such as a Bosch battery have a battery management system (BMS) integrated into the battery that actually tells you the current capacity and also how many charge cycles it has gone through.

But no matter what type of battery you have you’ll sooner or later be asking yourself the all-important question: how can I replace my e-bike battery?

Down below Electric Bike Report dives into this question and more in greater detail.

Are E-bike Batteries Interchangeable?
Where Should I Go to Get a Replacement E-Bike Battery?
Replacement Batteries from Original Manufacturers
E-bike Manufacturers Own Brand Batteries
Batteries for Out-Dated Motor Systems
Non-Removable Frame Integrated Batteries
Third-Party Replacement E-Bike Batteries
What Should I Do With My Old E-bike Battery?

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E-Bike Batteries: Volts, Amps, & Watt Hours Explained

What Are These Volts, Amps, and Watt-Hours? How Battery Specifications and Capacity Equate to Capability and Cost

Understanding e-bike batteries can be challenging, even for those of us in the know; the nitty-gritty details are figured out by electrical engineers with years of education and experience under their collective belts – and for good reason, it’s all chemistry and math over there!

You’ll encounter a host of terms when reading about e-bikes or looking at electric bike battery specifications: things like battery size, capacity, voltage, amp hours and watt hours. Some of these words are more-or-less interchangeable, others are related but distinct. All of them can be confusing, but they are also hugely important in understanding electric bikes and their capabilities – most notably when trying to interpret how far they can take you before needing to be recharged.

In this guide to e-bike batteries, the helpful writers at Electric Bike Report will help you to understand the meaning of common battery terms and their relation to the performance of the electric bikes they power.

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E-Bike Batteries Explained

Batteries are one of the core elements of electric bikes. They are needed to supply power to the motor, which in turn provides assistance to the rider, and reduces the amount of human effort needed to move the bike.

E-bike batteries come in various sizes, and can be mounted to the frame in different ways. Some are fully internal, and are sealed inside the bike’s frame. As such, they are not removable, except by using special methods and tools available to professional technicians. Others are removable for easier charging and replacement, whether mounted completely externally (outside the frame), partially recessed (sunken into the frame to some degree), or completely recessed (sunken entirely and nearly invisible on the bike).

Regardless of their type, all e-bike batteries are actually battery packs, and are made up of groups of cells, similar to the standard AA or AAA batteries used in everyday applications. The number of cells and the method used to cluster them together determines how quickly they can provide power and how long they can continue to supply it.

In contrast to standard AA or AAA batteries, however, those used in e-bikes are most commonly rechargeable lithium-ion batteries similar to those used inside smartphones and in conjunction with cordless power tools. Lithium-ion batteries are efficient and can be recharged hundreds or even thousands of times if cared for properly. The Light Electric Vehicle Association, or LEVA, has a great article that they allowed us to re-publish regarding proper battery care and safety to ensure maximum life span.

Fully integrated batteries such as the one on the Velotric Nomad 1 can match the bike’s color and disappear into the frame.

Electric Bike Battery Terms and Definitions

Before we dive deeper into the details, let’s consider a couple of examples of e-bike battery specifications in relation to how they usually appear:

36V_,14.4 Ah

48V_,672 Wh

V = Volts and Ah = Amp-hours

V = Volts and Wh = Watt-hours

Both examples convey two basic measurements, albeit a little differently. In both examples, we see volts first; this measurement relates to the availability of the electrical energy the battery can deliver. Next, either amp-hours or watt-hours are shown; these represent a battery’s capacity, or the amount of power it can store.

Let’s define these words (and a few helpful additional terms) a bit more clearly:

Current: the flow of electricity, or transfer of electrons, through a circuit.

Circuit: a closed system of wires and electrical components through which current can travel.

Volts (V): the amount of electrical force or pressure the battery can produce; the speed of the battery’s output of current. This is also sometimes referred to as the electromotive force, and is more specifically the speed at which electrons move through the system.

Note that this is a nominal rating that is used for classification purposes. In reality, a battery’s voltage varies based on the amount of power being drawn from it at a given moment, as well as the battery’s present level of charge. As current is drawn from the battery, its voltage decreases. This can be seen in an e-bike battery voltage chart.

Voltage is determined by the number of battery cells arranged “in series”.

Amps or amperes (A): a measurement of the strength of the battery’s output, or current. More specifically, the volume of electrons passing through the system. This is limited by the size of the wires making up the system. Larger wires allow more current, smaller wires allow less. Generally, systems with higher voltage should use smaller wires (that limit amperage) to prevent overheating.

Amps can also be thought of as the amount of energy being drawn from the battery by what it is powering, and can fluctuate from moment to moment. In the case of e-bike batteries and their motors, a greater number of amps are drawn as the motor works harder (i.e. going uphill or using only the throttle).

Amp-hours (Ah): a measurement of charge; the amount of energy that can be delivered through an electrical system over the course of an hour.

In the case of a 10 Ah battery, it can deliver 10 amps of power in one hour, or 1 amp of power for 10 hours, etc, depending on the needs of the component that is delivering power to.

Amp-hours are determined by the number of clusters of battery cells arranged “in parallel”.

Watts (W): a unit of power, determined by volts and amps; the amount of work that can be done by one amp of current delivered at 1 volt. The amount of work is determined by the rate at which the energy is used.

This measurement is generally applied only to an e-bike’s motor, but its battery must support the motor’s needs.

Watt-hours (Wh): another measurement of capacity. In this case, the amount of work that can be done, or the amount of power that is spent, over the course of an hour. This is a direct result of a battery’s voltage multiplied by its amp-hours.

As such, a 24V, 20 Ah battery and a 48V, 10 Ah battery might look different on paper, but they have about the same amount of energy. This makes watt-hours a more reliable indicator of capacity when comparing different batteries.

Controller: A device that limits the flow of electricity through a circuit, and prevents a battery from discharging its energy all at once. In terms of an electric bike, this is the “brain” that adjusts the pedal assist system, the amount of input the motor contributes, and the e-bike’s speed.

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The Electricity-As-Water Concept

All of the above terms describe the strength and total amount of energy in a system, but they can still be difficult to understand in a way that relates to normal, everyday life. For this reason, electrical concepts are commonly related to plumbing and the flow of water.

If we consider a large container filled with water, the container represents the battery itself, and the water inside the container represents current or electrical charge. The container can only hold so much water, so this is likened to a battery’s capacity.

Now, if the container is connected to a pipe or hose, that tube represents the wiring of the electrical system. Voltage can be thought of as the pressure forcing water through the tube. Amps can be thought of as the volume or amount of water flowing through the system, which can change based on the diameter of the pipe and how open the faucet is at the end.

With the faucet, or the flow as governed by the controller, fully open and the water flowing through a connected tube and into a bucket, the amount of water in the bucket after an hour can be compared to an amp-hour.

If the water is instead used to turn a small water wheel, a watt becomes the distance one measure (amp) of water can turn the wheel. And with these combined elements in place, we can determine the distance the wheel can be turned by a full container of water (watt-hours), and with regulation of the water’s flow through the faucet, how long it will take for the container to become empty.

Why Does All of This Matter?

In terms of e-bikes, the above terms affect primarily how fast they can accelerate, how much they cost, and most importantly for many potential buyers, how far they can travel (and for how long). To a lesser degree, other aspects of an e-bike are also influenced, including how confidently an e-bike can power up hills, and how much input its motor can provide.

E-Bike Battery Voltage = Speed and Acceleration

Most e-bikes use batteries that are either 36V or 48V, though some lower- and higher-voltage options exist. Lower-voltage options are usually not able to provide the level of power that most users desire, and in general, anything above 48V has the potential for safety risks from electrical shocks. 52V systems, while above that threshold, do have an advantage over 48V systems in that they are able to deliver a more consistent level of power over longer periods of time, but they are relatively uncommon.

When considering the aforementioned plumbing analogy in relation to the most common battery voltages, think of a 48V system as having greater “water pressure” over a 36V system. In practice, this means that a 48V battery will deliver power to an e-bike’s motor faster than a 36V system.

As such, the motor of a 48V system does not have to wait to access and use the power it receives, and will also get more power in the same amount of time. This means that – provided all other factors are the same – a motor receiving power from a higher voltage battery will accelerate quicker and be able to reach greater speeds than if it were fueled by a battery with lower voltage.

Rad Power Bikes’ RadCity 5 Plus uses a semi-integrated battery that trades visibility for easy separation from the frame.

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E-Bike Battery Capacity = Range

While there are many factors that influence an electric bike’s range, battery capacity is one of the primary influences and is generally a good indicator of potential distance. And as we have established, amp-hours and watt-hours are two different means of measuring an e-bike’s battery capacity.

If we consider e-bike battery specs in relation to cars, amp-hours are the equivalent of the gas tank. A greater number of amp-hours means more fuel in the proverbial tank, and therefore a higher watt-hour rating means an e-bike can travel a greater distance (or go faster for a shorter distance). Due to the previously mentioned relationship between volts, amp-hours, and watt-hours, if two batteries have the same amp-hour rating but different voltages, the higher voltage battery will have more watt-hours. For this reason, watt-hours are generally thought of as the most useful battery specification for the consumer.

This is where things start to get a little complicated. Since an e-bike’s battery interacts directly with its motor, the motor’s voltage, type, specs, and efficiency are also part of the range equation (as it turns out, this can be a very long equation).

All of the following factors (and many others) affect e-bike range beyond just its battery’s watt-hour rating:

Motor voltage and watt output
Rider and cargo weight
Weather and wind
Speed (and PAS setting)
Terrain (road surface and hills)
Number of stops/starts
Amount and proper timing of rider input (pedaling)
Tire size and tread type

The more extreme any of these factors are, the less range an e-bike battery will be able to provide, because the motor will need to do more work to compensate. As such, it will need to draw more energy from the battery to compensate, reducing the remaining pool of available charge.

E-Bike Battery Size and Cost

Generally speaking, an e-bike’s battery is its most expensive component. Again, considering how batteries are made up of clusters of individual cells, a greater number of cells equals a greater number of amp-hours and watt-hours, but also an increased cost.

For this reason, it is important to consider a practical range for your own personal needs, to ensure that you are not overpaying for a huge battery you don’t actually need. An extended range might look good on paper, but it might greatly exceed the distance you will regularly travel.

The external batteries on the Evelo Galaxy SL and Galaxy Lux are mounted unobtrusively beneath the cargo rack, and include integrated tail- and brake lights.

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E-Bike Battery Amp-hours and Motor Input

An e-bike’s battery voltage and watt-hours must match the needs of its motor. We have discussed how greater voltage in a motor/battery system equals more immediately available power and speed, but volts only go so far. A battery’s capacity also needs to support the nominal wattage of the motor it is paired with. Nominal means that the motor operates at that level MOST of the time, but can peak at higher levels when doing things that require it to work harder, such as traveling on an incline.

We’re crossing more into motor specifications here, but the two are related. A 250W motor will not provide as much power and assistance to an e-bike as a 750W motor. But a larger motor needs to draw more power from the battery – and therefore requires a battery with a greater number of amp-hours (and therefore, watt-hours) to operate effectively and provide a functional range.

Calculating E-Bike Range

Disregarding all factors aside from battery and motor specifications, it is possible to calculate a rough estimate of an e-bike’s range with some basic algebra. We have a separate, more detailed article on how to calculate the range of e-bikes, but a summary of the main points ties in nicely here as well.

A battery’s effectiveness in relation to its motor relates largely to its watt-hour capacity rating. As mentioned in the definitions section above, that can be calculated by multiplying volts and amp-hours as shown below:

Wh (watt-hours) = V (volts) x Ah (Amp-hours)

For example, let us assume that we are working with a 36V, 14 Ah battery. Using the equation above, we can determine that the watt-hour rating for this battery is 504 Wh. Let us also assume that this power source is compatible with three different e-bikes, each with commonly-sized rear-hub motors and controllers designed for a 36V system:

E-Bike 1 has a 250W motor, E-Bike 2 has a 500W motor, and E-Bike 3 has a 750W motor. We can divide a battery’s watt-hour rating by the motor’s watt requirement to find out how long the battery should power each e-bike:

E-Bike 1: 504 Wh / 250 W = 2.02 hours

E-Bike 2: 504 Wh / 500 W = 1.01 hours

E-Bike 3: 504 Wh / 750 W = 0.67 hours or about 40 minutes

Two caveats come into play here. First, as discussed previously, a motor’s wattage rating is nominal, and its actual output varies. The more its output exceeds the nominal rating, the less time it will take for the battery to be depleted.

Secondly, we established that these were rear-hub motors, which tend to be less efficient than mid-drive motors (one that is mounted at the bottom bracket). Mid-drives have a direct connection to the pedal cranks, and subsequently rely much more on rider input, which reduces the amount of work the motor itself has to do, and extends battery life. For this reason, a smaller 250W mid-drive motor can have the efficiency and range of a larger 500W rear-hub motor. Factoring in sub-types of hub motors can affect things further, but for this article, we’ll keep things as simple as possible.

For most folks, a quantity of time is not quite as useful as a unit of distance, so with some additional math, we can calculate a rough idea of an e-bike’s minimum mileage with one more step. Yes, this complicates things further, but the result is ultimately more relevant.

Ideally, you need to know your average travel speed (or velocity) on an e-bike, which can be figured out over time using a fitness tracker app such as Strava, but if you don’t already have that we can estimate roughly 16 mph.

d (distance in miles) = d (time in hours) x v (velocity in mph)

So if we’re considering the same 36V, 14 Wh battery and the same three e-bikes with different motor wattages from before:

E-Bike 1: 2.02 hours x 16 mph = 32.32 miles

E-Bike 2: 1.01 hours x 16 mph = 16.16 miles

E-Bike 3: 0.67 hours x 16 mph = 10.72 miles

Through these calculations, we can see that a motor paired with a battery that has watt-hours exceeding its nominal wattage will function for significantly more mileage than one with watt-hours under its nominal wattage. For this reason, we generally recommend at least a 1-to-1 ratio between a motor’s nominal wattage output and a battery’s watt-hour rating, i.e. a 500W motor and at least a 500 Wh battery.

E-Bike Battery Voltage and Amps = Torque and Uphill Capability

An e-bike’s ability to power up steep inclines is helped by its rider and gearing, but is determined also by torque, or a measurement of rotational power. This dips more into motor, controller, and wiring territory, and therefore more into the engineering aspect of an e-bike’s electrical system, but an increase in watts equals an increase in torque (since watts equal work that can be done). Since watts are directly proportional to volts and amps, increasing either will effectively also increase torque.

For consumers, motor specs are much more relevant to understanding uphill power than battery specs. Every e-bike motor has a torque rating in Newton-meters (Nm), which is the most important number when considering an e-bike’s hill climbing capability. A higher Newton-meter rating equates to better uphill performance.

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Understanding E-Bike Batteries

While the topic of batteries and electrical systems is certainly complicated – this article has only scratched the surface, really – we hope that you feel better able to understand e-bike battery specifications with this information.

It can be easy to ignore the meaning of the values included in the specs of an e-bike battery and default to the standard belief that bigger equals better. When you start to consider how larger and smaller battery-related numbers relate to the practical applications of an e-bike, you can better understand how these measurements meet your own needs.

We hope you feel like you’re a bit better armed with knowledge now as you search for the right e-bike for you, and if you need a little more help in that regard, you can always check out our e-bike buyer’s guide for more basics on e-bikes batteries, motors, and more.

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Electric Bike Report’s Testing Process Explained

How We Consistently Measure E-Bike Performance

Here at Electric Bike Report, it is our mission to provide detailed, honest, and objective reviews of each e-bike we test. We want to help you to understand how each product performs and feels, so you can better decide if it’s the right e-bike for your needs.

To do that consistently, we have established a series of standardized, real-world tests that allow us to gather data in a relatively scientific manner. It’s the best we can do without a sealed, climate-controlled lab that would cost millions of dollars to build and staff appropriately (though we’d happily accept donations toward the cause if anyone wants to contribute!). So yes, some human shortcomings are to be expected, and of course your personal results on your own e-bike will vary since there are a host of factors that can alter an e-bike’s performance on any given day. However, this approach allows us to roughly measure any specific e-bike’s individual performance, but also gives us the ability to compare models between various categories, classes, and spec levels. We do our best to keep things consistent, even having certain team members be the dedicated operators on tests where weight is a significant variable.

While our methods have evolved over time (and will continue to), we want them to be as clear as possible. For this reason, we have put together this list of the various trials that make up our testing process, with detailed explanations of each.

Circuit Test

Our test circuit consists of a paved 1-mile loop that includes four right turns and a small incline with 30 feet of elevation gain.

First, we make one lap on each e-bike we test with zero assistance from the motor. The e-bike in question is always turned on, but its pedal assist system (PAS) will be set to PAS 0. On this lap, we measure the time it takes to complete, as well as an average of the bike’s speed in miles per hour. We then repeat this process again for each of the bike’s PAS levels.

This test is usually the first we perform on every e-bike, because it allows us to familiarize ourselves with each product in a consistent way. Specifically, it allows us to understand how the bike’s motor engages, how effective its torque or cadence sensor is, and how it handles. It also gives us the chance to see what speeds the bike is capable of in each PAS setting, and informs us what settings to use on our next test.

It’s also important to note that we try to apply a consistent level of effort and maintain a steady pedal cadence throughout the test. We think of it as giving 70% – the type of pedaling you might do on a traditional bike if you were trying to get to work with time to spare, but didn’t want to show up sweaty. Maintaining this consistency makes it easier to separate our own input from that of the motor; we can focus more on how the motor behaves, instead of how much harder we’re able to ride with its assistance.

Range Test

This trial is actually two separate evaluations performed on our local network of paved multi-use paths here in St. George, Utah.

For each test, we pedal a fully-charged e-bike until its battery expires. One test is performed in the PAS setting that provides maximum motor assistance, which drains the battery quickly while allowing the rider to achieve high speeds. The second test is done in the PAS setting that provides the least amount of input from the motor while still drawing power consistently, which happens over a much longer period of time.

To be fair, this low PAS test can be somewhat subjective. In our experience, many bikes do not provide meaningful assistance in PAS 1, and often don’t help the rider beyond six miles per hour. In these cases, we increase the PAS level until we find a setting that provides an appreciable level of motor assistance. Typically, we stop once we see that the bike is allowing its rider to achieve 8-10 mph with near-constant motor input.

In each test, we measure the distance the bike was able to travel, its average speed, the amount of elevation it gained, and the time that elapsed throughout the process. Most of that data is gathered for optional, anecdotal use in our reviews, but we always report the bike’s mileage.

This test gives us an idea of each e-bike’s minimum and maximum range when used practically. There are many factors that influence the distance an e-bike can travel, and we cannot possibly account for them all, so the results from this test are considered to be a rough estimate. We can, however, use this data to compare to the range advertised by the manufacturer of the e-bike in question, and either reinforce or refute their claims.
[Read more…] about Electric Bike Report’s Testing Process Explained

Understanding the Differences Between Direct Drive & Geared Electric Bike Hub Motors

You’ve no doubt seen references to geared hub motors and direct drive hub motors (also known as gearless hub motors) in descriptions of e-bikes. Often the references mention the supposed pros and cons of each but seem to assume you actually know what the different terms mean. If you need a quick rundown of what these two different types of motor design are and which might suit you, then Electric Bike Report has you covered.

What’s the difference between direct-drive and geared hub motors on e-bikes?

The terms geared and gearless refer to the way power is transferred from the motor to drive the bike forward. In practice, the distinction usually applies to hub motors (found in the center of the wheels) rather than mid-drives (found around the pedal cranks) – the vast majority of mid-drives are geared motors.

Ask Electric Bike Report: Are e-bikes safe for seniors?

The team at Electric Bike Report fields a surprising number of questions on whether electric bikes are safe for seniors and older people.

We get so many of these questions, that we actually tailor-made a list of our recommendations of the best e-bikes for senior riders.

But to answer the question in short: Yes, e-bikes are safe for seniors. Not only are they safe, they offer a host of health benefits from low-impact physical exercise to boosts in mental and cognitive health.

But it makes a lot of sense that we get this question so often — cycling, at least before e-bikes grew popular, hasn’t always been the most friendly sport for older demographics. It’s an activity with a reputation for hard physical exertion; one where pedaling unaided up hills and over long distances, among other things, could be obstacles unkind to aging bodies.

That paradigm quickly changed as e-bikes gained popularity.

How Much Does it Cost to Charge Your Electric Bike?

How much electricity does an e-bike use?

The best way to answer this question is to look at the amount of energy e-bikes typically use and to compare that to other means of transport to show just how economical they are in power consumption terms – very little by most measures!

Comparing watts is the best way of measuring and comparing when answering the question; it’s really handy as not only is it a measure of electrical energy but it’s also a measure of energy consumed by any type of movement, from walking to flying and everything in between. As watts is a measure of instantaneous power, watt-hours are an even more useful measure – they are simply the number of watts an e-bike (or anything else) consumes in an hour – hence watt hours (Wh).

Watt hours are also commonly used to measure how much electrical energy is in an e-bike battery. 1000 Wh batteries are large for an e-bike but not uncommon. For ease of comparison let’s assume a 1000Wh (or 1 kilowatt hour – kWh) e-bike battery can take a single rider 100km (around 60 miles) – that’s quite feasible based on the many real-world tests EBR has done with our electric bike reviews.

Now let’s compare that measure of traveling 100km on 1kWh of electricity to other ways of getting around in the following graphic, all based on figures found at the Without Hot Air website.

Of course, many of the other means of transport here don’t use electricity but they all use energy extracted from various fuels at rates that can be equated to kWh. So an e-bike uses around one twenty fifth of the electrical energy used by an electric car to move and one fiftieth of the energy used by a plane. These are of course very rough figures based on averages and assumptions; but the point remains, e-bikes use very, very little electrical energy when compared to alternatives.

Now let’s look at just how much that electricity needed to recharge your e-bike will cost.

Calculating Range on Electric Bikes: How To Find The Long-hauler For You

Long Range E-Bikes: Intro

The electric bike world has plenty of sprinters, heavy lifters and high jumpers, but what about marathon runners?

There’s lots of options for long range electric bikes on the market today, from dual-battery eMTBs to sleek super commuters and everything in between. But, with batteries being the most expensive part of an e-bike, the question quickly changes from how far you’d like to go to how much money you’re willing to spend.

Herein lies the trick of long-range e-bikes: You’ve got to balance your distance needs with practicality and budget.

That balancing act is tougher than you might think, but armed with some basic information about a bike’s electrical specs, a little knowledge of your own pedaling abilities and (as always) a realistic grasp of what you’d like to do with the bike, you can confidently choose a long-distance e-bike that won’t cost an arm and a leg.

Is 250W enough power for an electric bike?

Aside from speed, power is probably the hottest topic — and selling point — in the electric bike world.

Conventional wisdom would say that when it comes to power, more wattage is better. But if that’s the case, why do so many high-end e-bikes come with what seem like smaller motors — and is 250W enough power for an electric bike?

There’s a few factors that dictate how much wattage an e-bike needs, ranging from the type of motor being used to how the e-bike was designed. It’s also helpful to understand what manufacturers are describing when they talk about motor wattage, and how U.S. law dictates how powerful an e-bike can be. This post will dive into those details and more.

The small but mighty front hub motor on a GoCycle G4i+, arguably one of the peppiest, torquiest and most compact 500W hub motors we’ve tested.

But here’s a short answer that I’m sure will ruffle some feathers: Yes, we’ve found that 250W is often plenty powerful for many e-bikes. There’s some caveats to that statement, but by and large a 250W motor is enough to give a rider’s pedaling a nice assist. Remember, an e-bike is still a bicycle — by definition at least a little physical effort is required.

500W vs. 750W E-Bike: Does wattage matter on hills?

Does size matter? It’s a query as old as time that, depending on who you ask and in what situation, is going to yield a broad and potentially colorful range of answers.

In the less colorful context of electric bikes, motor size (to most people) very much does seem to matter. The general consensus is that bigger is better. More watts equals more power; equals more speed; equals an easier time climbing hills. But is bigger always better, or can a carefully tuned smaller motor compete with sheer wattage?

We set out to explore this question with a simple test: A head-to-head uphill race between a powerful 750W rear hub motor e-bike and a 500W rear hub motor e-bike that the brand claimed had been specifically tuned for hill climbing.

The result of that test was about as we expected, with the more powerful bike winning our race, but the relationship between motor size and climbing ability is far more complicated than power alone.
[Read more…] about 500W vs. 750W E-Bike: Does wattage matter on hills?

Electric Bike FAQ

Understanding E-Bike Propulsion Methods and Which is Right for You

Defining E-Bike Throttle and Pedal Assist Terms

What Are These Volts, Amps, and Watt-Hours? How Battery Specifications and Capacity Equate to Capability and Cost

E-Bike Batteries Explained

Electric Bike Battery Terms and Definitions

The Electricity-As-Water Concept

Why Does All of This Matter?

Calculating E-Bike Range

Understanding E-Bike Batteries

How We Consistently Measure E-Bike Performance

Long Range E-Bikes: Intro

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