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Software Releases


You will find below a summary of the most important changes to the Stromer firmware. You can have the currently installed firmware version displayed via the menu as follows: MENU/SYSTEM/ABOUT

SUI FW = Firmware of touchscreen
TNT FW = Firmware of communication module

To enable your Stromer to receive a firmware update, switch it on. The Stromer  will need good cell network reception for at least ten minutes. On the SUI FW version 1.4.x and later versions, an indicator notifies you when there is an update ready to install. When the update is ready, activate the "(OFF)" switch. A dialog window appears on the Stromer touchscreen. Here you can choose whether to install the update immediately (Yes) or later (No). You can install the update immediately or postpone installation of the update up to seven times. You will then have to install it.

During the firmware update, the torque sensor values may change. To prevent possible assistance problems, proceed as follows:

Please calibrate the torque sensor after every firmware update. You can calibrate the torque sensor in the SENSOR menu. Make sure you are not applying pressure to the pedals, then press CALIBRATE SENSOR.



June 11, 2018

Various optimizations

  • Optimized Errorhandling, some more critical errors are logged and remain visible for diagnosis purpose.
  • Trip- and Totals- counter not affected by critical errors on the system
  • Clock does not reset itself after every new start. Relevant for bikes with battery firmware 0.9.6 or 1.9.6.




August 25, 2017

Optimized power management

  • Enhanced calibration of torque sensor during the ride
  • Increased braking power in recup mode of ST1 X
  • Optimized temperature management for the battery

Various bugfixes for Stromer OMNI App

  • Battery and motor temperature
  • Trip and total distance when connected to the charger



April 07, 2017

Recuperation and braking mode have been modified, enhancing the life of the battery

  • Recuperation cannot be activated at low battery temperatures
  • Recuperation cannot be activated when the battery is fully charged
  • As soon as the battery has warmed up a little or is no longer fully charged, recuperation and braking mode can be activated as usual

Modified theft mode allows theft mode to be ended without using a smartphone

  • Theft protection can be ended with the PIN
  • If the PIN is entered incorrectly three times in a row, the PIN input window will be locked for three minutes

Various bugfixes, including:

  • Status messages sent after switching on
  • Validation of status messages modified
  • Backward jumps of the total distance triggered by certain error combinations


January, 2017

Functions for the ST1 X and the BQ618 battery

  • Compatibility with the BQ618 battery
  • Compatibility with the CYRO Drive motor
  • Start-up screen with an ST1 X logo for ST1 X vehicles

Torque sensor calibration

  • Optimized calibration of the torque sensor while riding
  • A manual calibration of the torque sensor, via the sensor menu, is recommended after the update

SUI FW 3.2.X

This fleet-specific firmware was never released.

SUI FW 3.1.X

This fleet-specific firmware was never released.


November 08, 2016

Measures to improve communication with the Stromer OMNI app

  • Reduction in communication errors – problem with the backend
  • Invalid trip and total values rectified – if vehicle on charger
  • Optimization of automatic status message when switching off
  • Tuning is applied without restart

Optimized riding properties

  • Riding properties when maximum supported speed reached
  • Controlled acceleration in Move mode
  • Elimination of temporary acceleration after braking process

 Diverse bug fixes for SUI FW 3.0.3 – among others

  • Measures to prevent loss of support
  • Malfunctioning of power button
  • No acceleration after pushing back onto stand
  • No flickering of lights when switching off



August 09, 2016

This bug fix release is available to all ST2 S and ST2 with ST983 battery. Vehicles with ST814 battery and SUI FW 2.0.0 are not taken into account.

Optimized software update (only effective with consecutive updates)

  • Confirmation after successful update
  • Installation after wake up, switch on and off

Adapted handling performance at maximum speed

Stabilizing measures for ST983 battery

Stabilizing measures in charging mode

  • No menu access during charging process

Diverse bug fixes for SUI FW 3.0.1 – among others

  • Motor blocked after unlocking
  • Calculation totals



June 17, 2016

This bug fix release is only available for newly delivered ST2 S and ST2 with ST983 battery.

Diverse bug fixes for SUI FW 3.0.0 – among others

  • Brake sensor in move mode
  • Frozen speed indicator
  • PIN possible with less than 9 digits
  •  Tire dimensions ST2 S


SUI FW 3.0.1

May 27, 2016

This bug fix release is only available for the ST2 S and ST2 with ST983 battery.

Setting time

  • Time is set on the battery and saved
  • Time can be set in a one-time process for each battery
  • No renewed setting of time needed after changing battery

Various bug fixes for SUI FW 3.0.0 – including

  • Battery warnings – self clearing
  • Reduced power consumption in standby


SUI FW 3.0.0

April 18, 2016

This update is only available for the ST2 S and ST2 with ST983 battery. M99-Pro lamp and ST983 battery are not compatible with older SUI firmware versions.

Functions for ST2 S and ST983 battery

  • Light management for M99-Pro
  • Compatibility of ST983 battery
  • Speed display modified in accordance with wheel circumference of ST2 S

Torque sensor calibration in Sensor menu

  • To be performed if no or irregular assistance
  • When executing unload the pedals and sit on the saddle

Revised theft protection is to prevent user from riding off in error when bike is locked.

  • Braking effect when vehicle locked
  • Lights flash and PIN input field is displayed before the theft mode is activated

SUI FW 1.5.2

October 26, 2015

SUI FW 1.5.2 is installed on new touchscreens for Production and Service. It is not installed on all bikes across-the-board.

  • Support for new motor controller version
  1. Supports controller with built-in CAN protection unit

  •   New display setup for improved contrast
  1. Improved contrast calibration in Production display


SUI FW 1.5.0

May 19, 2015

  • Optimization of communication when ST2 is switched on:
  1. Position is updated every 10 minutes
  2.  Status is updated every 10 minutes

  • Optimized energy management when locked
  1. Reduced energy demand when locked
  2. More accurate indication of the battery charge level after unlocking
  3. Bike flashes only for the first 5 minutes after locking

  •   New error handling
  1. Smartphone recharged at the USB charging socket without generating an OMNI error
  2. General stability improvements


SUI FW 1.4.0

April 21, 2015

  • Battery charge display:
  1. A more accurate calculation approach for the battery charge display ensures the battery is fully charged up at the end of the charging process.
  2. IMPORTANT: For optimum charging results, the battery should ideally be charged and stored at room temperature. The battery cannot reach its full capacity in a cold environment.

  • New indicators to display mobile network reception:
  1. New indicator for GSM signal strength in the riding display
    The more bars are solid, the better the signal strength is
  2. New indicator for GSM signal strength in the riding display
    Circle with a line through it = GSM and GPRS offline
    G = GPRS online
    No G = GPRS offline
    NOTE: The ST2 can only communicate via the mobile network if there is a GPRS connection. So even if the bars indicate maximum signal strength, communication will not be possible if no "G" is displayed.
  3. New indicator for exchanging data packages
    - A flashing arrow pointing down means the ST2 is receiving data.
    - A flashing arrow pointing up means the ST2 is sending data.
  4. New indicator if new firmware is available for your ST2
    Flashing arrow in box = update being loaded
    Arrow in box = update ready for installation. The next time you switch on/off, you will be asked whether you would like to install the firmware.

  • The PIN input display disappears if there is no activity for 1 minute in the locked mode.
  • Responsiveness of the touchscreen has been optimized so that commands can be input more precisely and incorrect inputs are minimized.


SUI FW 1.3.0

Internal release was never published


TNT FW 1.01

January, 2016

  • Mobile communication is more stable
  • Has no influence on range of functions or handling


SUI FW 1.2.00

July, 2014

The firmware update optimizes the charging process when you charge the battery directly inside the ST2.

  • Flashing of the ST2 lights in the locked mode is reduced. Only the daytime running lights now flash.
  • Display of system messages is optimized.
  • Other adjustments
  • The firmware update supports new functions of the myStromer smartphone app (from app version: Argentum  / August 2014 ):
  1. The remote locking and unlocking function is replaced by the “AUTOLOCK” function. With “AUTOLOCK”, you can activate a timer for the automatic lock on the ST2.  Via app, you can determine a period of time after which your ST2 is automatically locked. To unlock your bike again, you must enter the PIN when you switch it on.
  2. You will now feel the adjustments that you can make when fine-tuning the assistance mode 2 via app much more strongly than before. Speed, torque and agility.
  3. New features are that you can make ST2 system settings such as time, language and units  via app.


SUI FW 1.1.00

April, 2014


  • System languages: German, English, French, Dutch, Italian
  • Time format: 12hr / 24hr
  • Leave regeneration automatically
  • Consideration of the braking mode in regeneration
  • New move mode display
  • PIN entry with numbers


SUI FW 1.0.00 / TNT FW 1.00

March, 2014

  • First release with the basic functions of the ST2

A software update takes approx. 1 – 5 minutes depending on the scope. Software updates are only sent if there is a mobile network connection.