Should You Derestrict Your Electric Mountain Bike?
Let’s face it: the speed limiter on an e-bike can be quite annoying, especially if your bike is limited at 15.5 mph (25 km/h). Online you can find numerous solutions to remove that speed limiter. Sounds quite tempting right?
From my experience, most riders know too little about the consequences of tuning their e-bike, not only for themselves but also for others. As I have quite some experience with a derestricted eMTB, I want to inform you about the ins and outs through this article.
In this article, we’ll go through how to derestrict your bike, the impact of tuning on motor and battery life, and we’ll discuss the legal consequences. I hope that my article encourages you to really consider whether it’s actually a good idea to derestrict your eMTB. My research has certainly changed my view on e-bike tuning!
What’s The Top Speed Of An eMTB?
The short answer is: an eMTB will go as fast as you can peddle. But the actual top speed depends on factors like: type of e-bike, your fitness-level, type of motor and gearing.
There are basically three types of e-bikes and eMTBs, each with a different speed limit: the pedelec (25 km/h or 15.5 mph), the speed pedelec (45 km/h or 28 mph) and the r-pedelec (unrestricted or 75 km/h or 46 mph). The pedelec generally has a 250W motor; the other variants can have a motor power of up to 750W.
When we talk about an eMTB, 9 times out of 10, we’re referring to the pedelec with a 250W motor and a speed limit of 25 km/h or 15.5 mph. The S-pedelec and R-pedelec are respectively considered a moped and a motorcycle in most parts of the world. You need a different license and/or insurance to be able to ride one of those. In this article, we’ll only focus on the ‘standard’ pedelec eMTB.
What’s worth mentioning, is that the maximum motor power and speed limit for e-bikes is determined by the governmental and local authorities. The regulations aren’t the same all over the world. Whereas the speed limit for pedelecs in Europe is 25 km/h (15.5 mph), it is 20 mph (32 km/h) in the US, Canada and New Zealand.
Of course, the speed limit and top speed aren’t the same. You are allowed to go as fast as you can, as long as you use muscle power instead of electric power. It then comes down to your fitness level and gearing what speeds you can achieve. The weight of the bike and drag of the motor will try to hold you back.
A derestricted eMTB however, will continue to assist you above the legal speed limit. Gearing and motor torque are now the main factors that will determine your top speed.
A test performed by myself on a private road, has shown that I was able to achieve a top speed of 55 km/h (34 mph) on my derestricted 2021 Trek Rail 5 with a Bosch Performance Line CX.
eMTB Rules And Regulations
Most eMTB riders are aware of the fact that tuning is illegal, but often don’t consider the legal consequences. Some research on this topic has certainly opened my eyes!
Why Is eMTB Tuning Illegal?
As mentioned before, there are regulations surrounding the maximum power and top speed of e-bikes. These rules exist to separate e-bikes from mopeds and motorcycles. Because of these rules and regulations, you don’t need a license, insurance, license plate, and you can follow the same traffic rules as for regular bikes.
If you derestrict your electric mountain bike to make it go faster, you basically turn it into a moped to which different rules apply. Since your eMTB doesn’t adhere to the regulations for mopeds, you can’t use it on the public road.
Sharing bike paths with other cyclists while doing high speeds, is very dangerous. You are only allowed to ride a derestricted eMTB on private land!
eMTB Tuning Penalties
First of all, in more and more countries authorities check for tuned e-bikes. In the Netherlands for example, the police check e-bikes by putting them on a rolling road to measure its top speed. If the motor doesn’t cut out after reaching the legal speed, the owner is greeted with a €290 or $315 fine. They can even confiscate your bike if they catch you multiple times!
If you get into a crash with other road users, there are some serious legal consequences. Depending on where you are in the world, chances are that you become liable for personal injury. This means that you are responsible for all the costs involved while there’s no insurance to back you up! You also risk getting a huge fine or even imprisonment in some countries.
In case of an accident, police or insurance companies will check your e-bike for modifications if they suspect that you were speeding. This puts you as a tuned eMTB-owner in a very vulnerable position. Even if you weren’t speeding and the accident wasn’t your fault!
How To Derestrict Your Electric Mountain Bike
Although you can’t ride a derestricted eMTB on the public road, you can still use it on private land.
There are a few ways to remove the speed limiter on an e-bike. You can go for an internally or externally mounted device or a software modification. The best pick for your bike depends on the software version and the make and model of the drive.
How Does E-Bike Tuning Work?
First of all, unlike what some people think, tuning an e-bike doesn’t give your more power. It’s all about altering the speed limiter which will make it feel like you’ve got more power.
Bicycle manufacturers do a very good job in preventing you from modifying your e-bike. Firstly, because they can’t guarantee the safety of a tuned e-bike. And secondly, they do this to protect the classification of an e-bike and the rules and regulations involved, as that’s in everyone’s best interest.
The way manufacturers do this, is to equip their bikes with anti-tamper software. When the software detects that the speed limiter has been altered, it will show an error code and switch to an emergency mode. Depending on the make and model of your drive, chances are that you have to take it to the dealer to reset it!
When it comes to tuning devices like a tuning-dongle, it’s all about being able to trick the system. They’re designed to make your bike’s computer think that you’re doing a lower speed than you actually are. Therefore you can go beyond the original speed limiter without the motor cutting off. A lot of devices are also able to display the correct speed and mileage on your display.
Manufacturers try to stay on top of tuning by rolling out updates on their motor software. Because of this, a tuning device or software may no longer function after an update has been applied by the dealer. Tuning will become more and more difficult in the future.
Derestricting your bike will cost you between €130-190 or $135-200 on average.
Externally Mounted Tuning Devices
The first way to derestrict an eMTB, is to fit an externally mounted tuning device like the Badassbox. This device is available for most motor brands, including Bosch, Shimano, Bafang, Brose, TQ and Yamaha.
An externally mounted device is the simplest way of tuning; it often doesn’t require any tools, works straightaway, and can easily be removed. It is designed to fit over the original speed sensor and modifies the signal in order to override the speed limit. The only downside is that these devices don’t display the correct speed on your display.
If you’re looking for a long-term solution to derestrict your electric mountain bike, then I’d advise you to continue to the next section. Because it’s externally mounted, it’s vulnerable.
However, I do think that these devices are a great solution for people that don’t want their eMTB to be derestricted permanently. You can easily remove the device and legally ride your bike on a public road.
Internally Mounted Tuning Devices
The second way to derestrict your eMTB, is via an internally mounted device or a ‘tuning-dongle’ from brands like Speedchip, Volspeed and Bikespeed. These dongles are available for most drive-systems, including Bosch, Yamaha, Brose and TQ.
An internally mounted system is one of the most professional ways to derestrict your eMTB. It takes a little more effort to fit, as it needs to be plugged into the system. It then adapts the sensor signal to the motor control. Some dongles will display the correct speed and mileage on your display. Error codes however, are still a big concern.
An internally mounted device is a long-term solution to derestrict your bike as it’s small, water resistant and usually sits inside your motor casing. Most devices work good with your display and you can turn it on and off through your display-controls. With some devices like the Bikespeed RSc, you can even tweak some settings.
If you need your bike to be road legal, then an internally mounted device probably isn’t the right solution for you. Although you can turn it off and it’s difficult to spot, it’s still present and requires tools to remove it. In case of an electrical issue or an error code, it can leave you stranded if you haven’t brought the right tools.
Tuning By Software
The third way to tune your eMTB, is through software tuning. For some e-bikes, it’s possible to remove the speed limiter without any hardware.
As touched upon earlier, the speed limit for pedelecs in the US, is 20 mph or 32 km/h. If you are outside of the US and you own an eMTB that’s also available in the US, you could run the US-software in order to raise the speed limiter (in theory).
I said ‘in theory’, as this is not a straightforward job and will require some research. I know of people with a Bosch Performance Line CX motor who made this work, but no certified dealer will help you with this. However, it would be a very durable solution with little to no chance of an error code!
For some motors it’s also possible to remove the speed limiter through aftermarket tuning software. Doing this yourself would be complicated, but I know of companies who can do this for you. It doesn’t work for all motors, but I know of people with a Shimano mid-drive unit who were able to do this. Some tuning-solutions even can be controlled through an app on your smartphone.
Remember that this is also a way of hacking the system, so there’s no guarantee that you won’t get an error code.
A downside of software tuning, is that it’s a permanent modification which can’t be removed easily. It’s illegal to use a tuned bike on the public road. Even if the software is turned off!
Mechanical Tuning
The fourth and last way to increase the top speed of your bike, is through mechanical tuning. Just like the Badassbox, this is also an externally mounted device, except it operates differently. An example is the SPEEDi from NLS Components which is available for basically all best-known bike brands like: Trek, Santa Cruz, Specialized, Giant, Yeti, Scott, Cube and Orbea.
The principle is based on slowing down the RPM of the magnet on your rear brake disc. This way, your bike thinks you’re doing a lower speed than you actually are. It does this through a magnet placed in a planetary gear system. Because of the gear ratio, the magnet moves slower than your rear wheel. It increases your speed limit by a factor of 1.5; 15.5 mph (25 km/h) becomes 23.3 mph (37.5 km/h).
In my opinion, although the concept is great, there are better tuning solutions. It’s somewhat of a permanent way of tuning as it requires tools to remove it from your bike. The reading on your display will also be off as it doesn’t alter the signal. And lastly, the gearing is subject to wear and tear so its lifespan will be limited.
The Impact Of Tuning On Your eMTB
The biggest fear of anyone tuning their e-bike, is that the motor and battery will fail. Which is understandable, as these components are very expensive to replace.
Motor And Battery Lifespan
As mentioned before, tuning doesn’t add any power to your drive. Installing a tuning device or software, therefore isn’t harmful for your system. However, riding your e-bike at high speed for a long period of time, of course does have an impact on motor and battery lifespan; more electricity runs through the system which is accompanied with higher temperatures.
For your battery, this means that it drains more quickly and you’ll have to charge it more often. Because every battery has a limited number of charge cycles, its lifespan is shortened. Higher temperatures accelerate this process as battery-cells degrade faster.
For the motor, tuning causes the motor to be put to work for a longer period of time at a high cadence. As a result, the internals of the motor such as your crankshaft bearings, will wear out more quickly. Worn bearing are usually the start of water ingress into your motor, which is very bad news. It is important to often check these bearings for play or any change in noise.
Although the story above sounds quite negative, I feel like I need to bring some nuance. If you mainly use your eMTB for actual mountain biking, the impact of tuning on your motor and battery won’t be that significant. Here’s why:
- Although the speed limit for pedelecs in the US, Canada and New Zealand is higher than elsewhere, there are no mechanical differences between a 20 mph and 15.5 mph version of the same drive. Therefore we can conclude that these motors are designed to assist you at speeds above 15.5 mph, but you will see an increase of wear and tear.
- In practice, you’ll rarely reach speeds above the original speed limiter during mountain biking. Using the same bike for commuting however, is a different story.
- The gearing of an eMTB isn’t set up to maintain a high speed for a long period of time.
Increased Wear And Tear
Riding your eMTB at high speeds, will cause increased wear and tear to your drive train, brakes, wheels and tires. Especially the high speed, smaller cogs on your cassette, will have a very hard time.
According to the formula of kinetic energy, if you double the speed of an object, the kinetic energy will increase by a factor of 4. Based on this, we could say that every component on your bike is affected by the increase in load. But in reality, you should see increased wear and tear on your drivetrain, brakes, wheel bearings and tires.
In other words: derestricting increases the load on your bike. Your bike wasn’t designed for that.
You’ll Lose The Warranty
A pedelec wasn’t designed to be an s-pedelec or r-pedelec. The manufacturer of your eMTB therefore doesn’t want to be held responsible for any failures as a result of tuning. Derestricting immediately voids the warranty of your e-bike.
Another reason why manufacturers discourage people to tune their bike, is to protect the regulations surrounding pedelecs. At the moment, you don’t need an insurance or special license to be able to ride a pedelec. If many accidents occur due to tuning, those rules might change.
Your eMTB stores data about usage. Before the manufacturer repairs your bike under warranty, the dealer must perform a diagnose of the system to proof that the bike hasn’t been tampered with. Even if you remove the tuning-device, the system will still show that it was tuned.
Updating Is No Longer Possible
As mentioned earlier, manufacturers roll out updates to improve the system, but also to prevent tampering.
If you update your derestricted bike, chances are that the new software will expose that your bike has been modified, and it may no longer work after. Therefore the advice is: do not update your e-bike after a tuning device has been fitted. But keep in mind that you’ll also be missing out on beneficial updates, like increased torque, better efficiency or bug fixes.
Selling Your eMTB Might Be A Problem
Something that most e-bike tuners don’t consider, is the fact that tuning can’t be undone. You can of course remove the tuning device or software, but a diagnose of the system will always show that it was tampered with.
When it comes to selling your derestricted eMTB privately, it’s only fair to inform the second owner about the consequences for warranty and updates. This will probably make selling your bike a bit more difficult, but in my opinion, it’s only the right thing to do. If you don’t like being misled yourself, then don’t do that to others!
To learn more about buying a second hand eMTB, click here.
eMTB Tuning: My Personal Story
I’ve ridden a derestricted eMTB 10.000 km (6200 miles) over a period of 3 years. Because I believe my experience can be useful to others, I’ve decided to document it in a separate blog post.
In that article, you can read about the long-term impact of tuning on an eMTB. We’ll discuss topics like:
- How I tuned my bike
- Problems that I encountered
- How I use my bike
- My overall thoughts on tuning
Right now, I’m still writing that article. As soon as it’s done, you’ll find the link here.
Alternatives For Derestricting An Electric Mountain Bike
If derestricting your eMTB isn’t for you but you’re still annoyed by the speed limiter, then there are a few things you can do in order to make your life easier without breaking the law.
Accept the limiter
The first solution is a change in mindset. When I first rode my eMTB, it was all about speed. I wanted to ride my bike fast everywhere. With that much torque, I accelerated very quickly towards the speed limiter, which then felt like hitting a wall. It annoyed me quite a bit.
Nowadays, I’ve exchanged my need for speed for speed for the need for range. I know where my bike excels and I now use its power differently. I don’t consider an eMTB as the best solution for going very fast very easily, but they are very capable in some very technical terrain.
What I suggest you to do, is to switch to a lower mode of assist whenever your can. It will lower your average speed, but does make it more of a workout. Your body will reward you with dopamine and serotonin afterwards!
It’s all about accepting the fact that your eMTB will be faster in some sections, but a regular bike will be faster in other sections. But as you ride more and more, that mindset will come naturally over time.
Try Some More Technical Trails
As an addition to the previous section, instead focusing on speed, you could also try some more technical trails. That’s what an eMTB was built for and where it will shine.
Get A Lighter Bike
Alright, this might sound a bit drastic, but the following may be a solution for those that are in the market for a new bike. If speed is your thing, then a lighter bike might be the right solution for you.
Most people assume that it’s the drag of the switched off motor that makes it hard accelerate beyond the speed limiter. But actually, it’s mainly the weight of the bike.
Nowadays, manufacturers sell ‘SL’ (Super Light) versions of their eMTBs, which can be up to 6 kg lighter than your standard eMTB. One of the factors that makes them lighter, is the smaller motor and battery. Although they are a less powerful, they are more agile and provide a more natural feel.
Should You Derestrict Your Electric Mountain Bike?
We’ve now come to the conclusion of this article. And to be honest, there’s no definite answer to whether you should derestrict your eMTB. It comes down to where you ride and how you use your bike.
First of all, if you only ride your eMTB on private land, then it’s up to you whether you should do it or not. Keep in mind that you could be faced with high maintenance costs and that your warranty is void. Fundamentally, derestricting isn’t harmful for your bike and there are numerous ways to do it. However in the long run, you should see increased wear and tear.
When it comes to riding a derestricted eMTB on the public road, many people don’t consider the consequences of their actions. You’re not only a real danger to yourself, but more importantly, also to others. Getting into an accident has some serious legal consequences that should not be underestimated!
Also think about your role when it comes to protecting the classification of e-bikes and pedelecs. Just like yourself, we all want to continue to enjoy our e-bikes in the same way as we’re doing right now. Many incidents with tuned bikes might change the government’s view on regulations. We don’t want electric mountain bikes get be banned from trails!
Finally, I would like to say this: I get that especially the 15.5 mph speed limiter can be annoying. But I want to emphasize that removing that speed limiter, doesn’t only affect you as a rider. If the speed limiter is still bothering you that much, reconsider the way you use your bike. An eMTB might not be the right tool for the job.
Frequently Asked Questions
Simply put, you can’t ride a derestricted eMTB anywhere, unless it’s private property. However, rules and regulations are different around the world. When it comes to bike parks, it’s up to the owner of the park whether you are allowed to enter.
Not all e-bikes can be tuned. It depends on the make and model of the motor and the software version. For the most common brands, you can find various tuning solutions like the Badassbox or a tuning dongle from Bikespeed or Speedchip.
Fitting a tuning device isn’t difficult and requires some basic technical knowledge. The externally mounted devices are the easiest to install; the internally mounted variants take a bit more effort. Tuning by software is specialist work.