How Fast Are Electric Bikes: What is the fastest street-legal electric bike?


Electric bikes are often sold on the fact that they are a faster option for riding or commuting. Given the recent rise in the popularity of biking in general, many people will be wondering just how fast an electric bike is. As a regular bike rider who owns an electric bike, I thought it would be helpful to clarify for new cyclists just how fast an electric bike is, and whether or not it will be able to meet your needs. So, how fast is an electric bike?

Even the fastest electric bikes in the US are speed restricted to 28mph (45 km/h) when being used on the road. This means that even though the bike is able to go faster, the motor will cut out at this speed and stop assisting you. Some countries, such as the UK, have even stricter speed limits (15mph).

So, we’ve established that electric bikes can go as fast as 28mph while being street legal in the US, but what are the speed restrictions where you live? I take a look into this, as well as the other factors that impact your electric bike speed in the rest of the article.

How fast are electric bikes?

Electric bikes come with a wide range of top speeds and the speed at which they go will depend on a variety of different factors.

Type of motor

One of the most important factors in the speed of an electric bike is the size and type of the motor itself.

Electric bikes can come with a range of different motor sizes, from as little 250W up to 25,000W. However, in reality, the majority of electric bikes you see will have a motor between 250W and 750W. This is because these motors are legal in the majority of countries whereas motors above this size often require a license and are counted as electric motorbikes.

As a general estimate, the speed limits for different size electric motors can be seen below.

Motor Size (Watts)Estimated Top Speed
250W30km/h (18.5mph)
500W40km/h (25mph)
750W45km/h (28mph)
1000W50km/h (31mph)
1500W60km/h (37mph)
3000W75km/h (47mph)
5000W90km/h (56mph)
10,000W110km/h (68mph)
25,000W160km/h (99mph)

However, this is a fairly large simplification of the speeds that different motors will supply, as in reality, you may find that some 250W motors are able to deliver as much torque as some 500W options.

It is also important to remember that the power of the motor will also impact other areas of the bike, for example, a larger motor will require a larger battery which in turn will limit the range of your bike.

Class of electric bike and speed limiters

The speed at which you can go on an electric bike will also depend on the class of electric bike you own.

US Electric Bike Classes

Within the US, electric bikes are classified is into classes 1, 2 or 3. It is worth confirming the laws for the particular state that you live in, as they will each have their own rules and regulations around which class of bike you are allowed to ride and where.

ClassSpeed LimitThrottle or Pedal Assist
Class 120mphPedal-Assist only
Class 220mphThrottle Assisted
Class 328mphPedal-Assist Only

EU Electric Bike Classes

Within the EU, electric bikes have 4 separate classes. Each country within Europe has its own rules for the individual class of bike, and so it is worth confirming what the laws in the particular country that you plan to ride your bike are.

ClassMotor SizeSpeed LimitThrottle or Pedal AssistNumber of Wheels
L1e-AUp to 1000W25mph (40km/h)Both2 or 4 wheels
L1e-BUp to 4000W28mph (45km/h)Pedal-Assist Only2 wheels only
L2eUp to 4000W28mph (45km/h)Both2 or 3 wheels
L6eUp to 4000W28mph (45km/h)Both4 wheels only

Weight

As with all types of bikes, the total weight of you, your gear and your bike will have a large impact on your speed. This is especially the case for electric bikes which can weigh much more than their traditional bike counterparts. For example, the average electric bike weighs between 18kg and 22 kg whereas a traditional non-electric bike can weigh as little as 10kg (half the weight). 

On top of the weight of the bike, you also need to take into account the weight of any cargo or gear you are carrying with you. For example, some electric bike riders will carry a spare battery with them to increase their bike range. These can weigh between 5kg and 10kg on their own, and so this can significantly increase your overall weight.

It is worth noting that when using the motor of an electric bike, you will be much less affected by your weight than if you were using a traditional bike. For example, cycling with 10kg worth of camping gear, will decrease your speed much more on a normal bike than on an electric one. This is because the motor in the electric bike can help to take on some of the extra workload.

Pedalling

How fast you go on an electric bike is also dependent on how much you are pedalling.

While individual electric bikes will have speed limit restrictions based on the class of electric bike and where in the world you are, all of these speed limits only apply to the speed at which the motor can assist you.

Electric bikes can cycle as fast as you can pedal them, however the motor will cut out, and stop assisting you, once you reach the speed limit of that particular model.

For example, I have an electric bike in the UK (where they have speed limits of 15.5 mph). I have cycled on this bike at speeds of around 30-40 miles per hour on some very steep downhill descents. however the motor was only working for the time when I was cycling at less than 15.5 mph.

This means that theoretically, an electric bike can go as fast as any other bike you can pedal (it will just be harder as it will weigh more).

Pedalling assistance levels

The amount you pedal has a greater impact on your speed with class 1 and 3 electric bikes. That is because these bikes have no throttle and so only add to your speed while you are pedalling the bike yourself.

The majority of bikes will support your pedalling by a certain percentage depending on what power level you set the bike to. For example, an electric bike may add an additional 50%, 100%, 175% or 250% of power, depending on the bike you are using and the particular mode it is in.

For example, if you are cycling with 100 Watts of your own energy, an electric bike may increase this up to 150W (an extra 50W) while on its lowest ‘eco’ setting of a 50% boost.

Cycling conditions

There is also a large range of different factors that can affect how fast any bike is, this includes electric bikes as well.

Ascent or Descent

For example, whether or not you are cycling up or downhill will have an impact on your speed. As I already noted, the fastest I’ve ever been on my electric bike was during a very steep descent.

Headwind or tailwind

Many regular cyclists will know how important having the wind on your side can be. In fact, it surprised me to learn that cycling will a headwind (the wind blowing into you as you cycle) can slow you by about half of the wind speed itself.

For example, if you are cycling at 15 mph on a flat road, a 20mph headwind can drop your speed to as low as 5 mph for the same power output.

Road Quality

The quality of the road you are cycling on will limit the speed that you are able to ride.

Riding off-road will obviously reduce your speed, as you will have reduced grip and will likely have to slow down to account for this.

Even for riding on the road, the quality of the road surface will be important. For example, if you are cycling in an area with a lot of potholes you will also have to slow down to adjust for these.

Will an electric bike make you cycle faster?

Many people will purchase an electric bike under the impression that it will be much faster than a non-electric bike. However, in my experience, while electric bikes can be faster than traditional bikes, this is only the case in certain situations.

If you are a slower cyclists

As you might expect, if you are a slow (or even average) cyclist, then an electric bike is likely to improve your cycling speed.

The average cyclist will ride at between 10 and 12 mph (around 18km/h). This means that if you cycle at this speed, an electric bike is going to significantly improve how quickly they are able to get from A to B (even in the UK where the electric bike speed limit is the strictest in Europe).

If you want help maintaining your speed over a longer period of time

Depending on the speed limits set on electric bikes in your country, you may find that an electric bike actually decreases your speed on shorter journeys. For example, I live in the UK and so the 15mph speed restriction on my electric bike actually means that on smaller journeys, I am often faster on my regular road bike.

This might be confusing, however the road bike weighs a lot less than my electric bike, and so I can ride at an average speed of 20mph on my road bike, whereas I only ride at 15mph on my electric bike.

To put this to the test I set myself a 10-mile and 50-mile route around London. Over the last week, I rode each route on both my road bike and electric bike.

DistanceRoad BikeElectric Bike
10 miles32 minutes40 minutes
50 miles3 hours 39 minutes3 hours 17 minutes

As you can see, the shorter route was actually quicker on my road bike, however, on the longer ride where I was not able to maintain the speed for the whole route, my electric bike was quicker.

Using this information I can estimate that for journeys under 20 miles I will be quicker on my road bike.

If you want to improve your speed consistency

For example, a 30-minute commute on a regular bike could take as long as 45-minutes if you have a headwind or aren’t feeling your best, however with an electric bike it will always take you a set 30 minutes (possibly less).

What is the top speed of electric bikes?

What is the fastest electric bike?

The fastest electric bikes currently in production are the HPC Scout Pro and the Delfast Top 3.0. Both of these bikes come with a 3000W electric motor allowing for some serious speeds. The Delfast Top 3.0 currently holds the world record with a top speed of 50mph (without pedalling).

Obviously these bikes are not street legal, however the HPC Scout Pro does come in different street legal versions such as a 750W option available. These will obviously not be able to obtain the speeds that the 3000W versions are.

What is the fastest road-legal electric bike?

The fastest road-legal electric bike will be dependent on the country you live in. For example in Europe, electric bikes are limited to a motor size of 250 watts, (meaning you won’t be able to get over 25 km/h).

The US has more relaxed rules in comparison, however, this will depend on the state you live in. E-bikes in some areas of the US are able to carry a 750W motor allowing much faster speeds.

As far as the fastest 750W electric bikes go, the BAKCOU Flatlander is the fastest choice, advertising speeds of up to 35mph.

Overall

As you can see, electric bikes come in a wide range of different speeds, and there are many factors that influence how fast you will actually be going.

If you are thinking about getting an electric bike, take a look at my article where I look into how much an electric bike will actually cost you.

Mark Holmes

30-year-old doctor with an interest in cycling, bikepacking, and statistics.

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