The Xiaomi Mijia Electric Scooter 1S (often referred to as the S1) is deservedly considered one of the most popular devices in its class due to its reliability and stylish design. However, many owners face a software limit to the maximum speed, which in Russia and Europe is 25 km / h, or sometimes less. The desire to squeeze the maximum out of your vehicle is quite natural, especially when the technical capabilities of the device allow you to go faster.
In this guide, we’ll look at proven ways to increase the speed of the Xiaomi S1 without causing critical damage to the battery and motor. You’ll learn about software methods for unlocking through a change of region, physical adjustment of the controller and replacing firmware. Remember that any software intervention removes the warranty, so weigh all the risks before you start work.
There are several levels of modification, from safe change of region in the application to complex soldering of components of the board, we will go through all the stages, from the simplest actions that every user can do, to advanced tuning. Your safety on the road must remain a priority, so remember that as speed increases, braking distance and load on the nodes.
Analysis of staff limitations and technical capabilities
The Xiaomi S1 firmware tightly limits the speed of the motor-wheel, which is done in accordance with the laws of many countries where electric vehicles are divided into categories. The S1 is characterized by a 300 W (peak 500 W) engine that is physically capable of developing up to 30-32 km / h if you remove the software "collars", the lock is implemented at the level of a controller that receives data from Hall sensors and limits the current supply.
It's important to understand that just adding gas is not going to work because of the BMS (Battery Management System) algorithms, the battery control system monitors the voltage and discharge current. If you try to accelerate sharply or drive at extreme speeds for a long time, the protection can go off, and the scooter will force you to reset speed. Temperature also plays a key role: when the stator windings overheat, the controller will automatically reduce power.
⚠️ Attention: Exceeding the normal speed significantly reduces the range. 20 scooter 30 mile 30 km/h autonomy may fall to 18-20 km due to aerodynamic drag, which grows exponentially.
Technically, the S1 is built on proven components, but they are fitted with a safety margin that allows you to withstand moderate tuning. However, constant use at the limit leads to accelerated wear of bearings and degradation of the cells of the lithium-ion battery. The controller in this model has passive cooling, and its heating at high currents is normal, requiring control.
The method of changing the region in the application Mi Home
The easiest and safest way to increase the speed of the Xiaomi S1 is to not have to be soldered or connected to a laptop. It's all about regional settings. In some countries, the limits are higher, and changing the region in the user profile allows you to unlock these values. First, make sure you have the latest version of the Mi Home or Xiaomi Home app installed.
The procedure is as follows:
- 📱 Open the app and go to the profile (the profile tab or the person icon).
- 🌍 Click on "Settings" and select "Region).
- 🇺🇸 Change region to United States or India, and in these versions of firmware, the limit is often 30 km/h.
- 🔄 Reconnect the scooter to your smartphone via Bluetooth.
After changing the region, the scooter may offer to update firmware. Accept the update, as the new version of the firmware contains the changed speed limits.
This method does not always work, as Xiaomi periodically closes these loopholes in new versions of the software. If after changing the region and updating the speed remained the same, then your version of the controller or firmware has more stringent locks. In this case, you will have to use more complex methods. Mi Home application sometimes caches old data, so it is recommended to completely delete the application, clean the cache of the phone and install it again.
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Before changing the region, be sure to write down the current settings (Bluetooth password, headlight settings, recovery mode), since after flashing, they can be reset to factory values.
Software unlocking via PC and XIAOYU
If the change of region doesn't work, a deeper firmware comes to the rescue), USB-cable (often you need a special cable for charging with data transfer) and utility XIAOYU (This method allows you to fill custom or modified firmware, which cut out the speed limiters.
The firmware process requires care, and you first need to put the scooter into debugging mode, usually by sequential pressing of the on and off buttons, or through a special diagnostic menu.
1. Connect the scooter to the PC via USB.
2. Launch the XIAOYU utility.
3. Press the "Connect" button (Connect)).
4. Select the firmware file (.bin) with the "Speed Unlock" modification.
5. Press Upgrade and wait until the process is over.When you're firmware, the lights on the scooter will flash, and you can't cut the power or the cable until you're done, or you'll get a brick.
Once you've successfully reflashed, the scooter will reboot. Check the speed in the app or by eye. Often, as you unlock the speed, the recovery algorithm changes, making the braking more smooth or sharp. Castom firmware can also display a more accurate percentage of battery charge, removing the "last mile" effect when the charge drops from 30% to 0% per minute.
☑️ Checklist before firmware
⚠️ Note: Using third-party firmware carries the risk of disruption BMS. An incorrect file can lead to incorrect calculation of battery capacity, which is fraught with a deep discharge of cells and their failure.
Physical modification: jumper and controller
In some versions of the Xiaomi S1 (especially early or specific markets), the speed limit is not only tightened in software, but also implemented physically through the presence or absence of a jumper on the controller board, which requires partial disassembly of the scooter and soldering iron skills.
To access the controller, you need to:
- 🔧 Remove the deck (platform) of the scooter, unscrewing the screws around the perimeter.
- 🔌 Disconnect the battery and remove the protective cover of the electronics compartment.
- 👀 Find a contact platform with marking on the controller board "SPEED" or similar (often two contacts that need to be closed).
Closing these contacts (by junction or soldering) changes the logic level at the controller's input, informing the controller that the restrictions are lifted, and then the scooter can reach speeds of up to 30-32 km/h.
But this method doesn't work for all board revisions, because newer models may not have a physical junction, but they may have a software restriction, and a sloppy soldering can short-circuit and cause the controller to fail, and the controller is an expensive node, and it's more expensive to replace than the potential benefits of speed increases.
What happens if you make the wrong contacts?
Comparison of tuning methods: table
To make it easier for you to choose the right option, we have put the main characteristics of the methods in a comparative table. Each method has its pros and cons, which should be considered based on your technical skills and willingness to risk the guarantee.
| Method | Difficulty | Risk of loss of guarantee | Speed increase | Safety for BMS |
|---|---|---|---|---|
| Change of region | Low. | Low (often unnoticed) | up to 30 km/h | Tall. |
| Flashing (PC) | Medium | High (fixed in logs) | up to 32-35 km/h | Medium |
| Physical jumper | Tall. | Critical (autopsy) | up to 32 km/h | Medium |
| Replacement of the controller | Tall. | critical | up to 40+ km/h | Depends on the setting. |
As you can see from the table, changing the region is the safest and most affordable method for most users, it does not require opening the case and special tools. More radical methods give more gain, but require a deep knowledge of the Xiaomi S1 device.
Controller replacement and advanced tuning
For those who want to get the maximum performance, you can replace the regular controller with a more powerful analogue, for example, from VESC or reinforced versions from Xiaomi (48V version), This upgrade allows not only to increase the speed to 40-45 km / h, but also to improve the dynamics of acceleration.
Installing a new controller requires re-switching the motor wires, Hall sensors and connecting to the battery through the appropriate connector. Often you have to rework the body or attachment location, because the dimensions may differ, the power of the new controller must match the characteristics of the motor, otherwise the windings will burn very quickly.
Advanced users also switch batteries to more-voltage ones (for example, from 36V to 48V), which gives a significant increase in speed and range. However, this is a complex engineering task, requiring recalculation of BMS parameters and possibly replacing the charger. High-capacity lithium-ion batteries are expensive, and the cost of such a tuning is often questionable compared to buying a more powerful model of a scooter.
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Replacing the controller and battery is a way for enthusiasts to experiment, and software unlocking is enough for normal urban driving.
The impact of tuning on resource and security
Do not forget that the increase in speed is an increase in loads on all nodes. The braking system Xiaomi S1 (electronic + disc brake) is designed to quench inertia to 25 km / h. At speeds of 35 + km / h, the braking efficiency decreases, and the distance to a full stop increases. It is recommended to regularly check the wear of brake pads and tension of the cable.
The motor-wheel warms up more when the currents are high. If you often drive at top speed on a slide, there is a risk of overheating the magnets (irreversible demagnetization) or melting the winding varnish. Watch the temperature of the wheel with your hand after the trip - it should not be too hot to touch.
⚠️ Note: The operation of a modified scooter on public roads may be prohibited by local law. Use the increased speed only in closed areas or where permitted by law.
Suspension (although there is no suspension in the S1, the tires play the role of cushioning) and the frame, shocks at high speed are perceived more acutely, which can lead to cracks in welds or breakage of the folding mechanism, Regular inspection of mounts and bolts becomes a mandatory procedure for the owner of a tuning scooter.