Built for decades. That part never changes.

It seems that the bike is locked via the app - in that case, the LED on the button will blink red twice when the button is pressed. Please connect the bike to the app and unlock it. To do this, first make sure that the connection is active.If you see a red dot next to the Bluetooth symbol (see below), please tap it to reconnect the bike to the app. Once the dot turns green, the bike is connected to the app. Otherwise, some functions, such as unlocking, may not work smoothly because there is no active connection.

If the app connection doesn’t work immediately, please try the following:

• Make sure that you have a good signal strength (i.e., mobile network reception - Wi-Fi does not matter here) at the location where your bike and phone are. If the bike is in a basement or similar location, the app connection will most likely fail, as GSM signals are often unavailable there.
• Check that you have the latest app version (version 3.1.1 for iOS and 3.1.0 for Android).
• Go to your phone’s Bluetooth settings. Under “Connected devices,” delete, forget or ignore (the wording may be different depending on your phone model) all previous connections named AMPLER, AMPLER2 or AMPLER3. These might be hidden under “See all.” Remove the connection completely. Here is a more detailed explanation for Apple devices, the photos below explain it for Android devices:

Is everything else on your bike working as usual? Can you switch it on using the button or in the app, and does the bike then provide motor assistance, do the lights work, can you connect the bike to the app, etc.?
How is the charger functioning? Does the LED light turn green when you plug the charger into the power outlet, and does it switch to red once you connect it to the bike?
This helps determine whether the issue is actually with the display or whether there may be other or bigger issues within the bike’s system. If only the display is not functioning, proceed with the steps below.
Have you already tried performing a firmware restart(either by pressing the button for about 7-10 seconds or by tapping in the app on “More” → “System maintenance” → “Restart firmware”)?If this does not help immediately, please put the bike into sleep mode.
You can do this either through the app (“More” → “System maintenance” → “Sleep mode”) or by holding the button for about 40 seconds. Your bike will then enter sleep mode and no longer respond to button presses. Afterwards, wake the bike again by connecting it to the charger.Is the display now working as usual again?

The initial expected range you see in the app or, for Generation 2 and Nova bikes, on the display, should be understood as a “up to” value. The range is continuously adjusted depending on riding style: as soon as the bike is under load - for example riding against wind, frequent stops and starts, or when it is moved from a warm to a cold environment, etc. - the range is adapted to these external factors.
Please also note that the battery level decreases even when the bike is not in use. This applies especially to Generation 2 and Nova bikes. For this reason, all our bikes should be charged approximately every 4-6 weeks to avoid deep discharge.With our Generation 2 bikes, a GSM/GPS module was also added. This module enables the use of tracking services (bike location tracking and movement alerts), which send data to our servers even when the bike is not in use. As a result, the battery level decreases even when you are not riding the bike. Bikes from earlier generations do not have these modules and therefore their batteries discharge more slowly.However, the main consumer of energy is (almost paradoxically) the battery management system (BMS) itself, which controls the operation of the battery.
Again, on Generation 1 bikes the system is much simpler and therefore the battery also discharges more slowly.

How does your Ampler function otherwise? Can you charge it normally, do the lights and button work well, etc.? Are there any error messages in the app? This helps to determine whether the issue indeed is with the motor support or whether there are any other issues with the bike's electrical system. Check first if the motor settings are turned on in the app.If the motor is on and support set high enough, but you still feel no reliable motor support during riding, check if the motor cable is connected securely. It is located on the left side of the bike near the rear axle, underneath the chainstay:

1. Check the cable for visible damages: could it be that it is pinched somewhere? Pay special attention to the area near the brake disk and see if there are any cuts, uninsulated wires or stretches on the cable.
2. Unplug the connectors and clean the contacts with rubbing alcohol or contact spray.
3. Remove each end of the cables from the guides and look thoroughly for damages on the cable sheathing. 
4. Are the pins in the cable straight, clean and undamaged?
5. Clean the sheathing and lead the cables through the guides again with care.
6. Plug the connectors together again tightly, arrow-on-arrow, without twisting.
7. Double-check: it should be plugged in tightly and there should be almost no space between the arrows.

Check this video to see the process (Generation 1).- https://www.youtube-nocookie.com/embed/cE8bBU-calk - Here are the connectors together as they should: tightly, arrow-on-arrow:If you are sure that the cable is securely fastened, but the motor support is still not working as it should, you can do a restart to the firmware. Do you have motor support after this again? If the issues persist also after the firmware restart, please calibrate the torque sensor of your bike. We recommend doing it every 3–6 months, or in case the bike feels over- or underpowered. Torque sensor calibration is done via the Ampler app, here's how it's done:

1. Adjust the left crank forward, parallel to the ground. 
   
2. Connect the Ampler app with your bike via Bluetooth.
   
3. In the app, click on „More”  → „System Maintenance”  → „Calibrate Sensor” and „Start” - the bike will then calibrate the sensor.
   
4. The LED lamp on the button lights up orange and changes to green when calibration is complete.

After that, perform a motor calibration. In the app, tap “More” → “System Maintenance” → “Calibrate Motor.” Follow the instructions shown in the app.⚠️Warning! During the calibration, the motor will start on its own and the rear wheel will begin to turn. It is important that you lift the rear wheel for the entire process to avoid damage or injury.After these steps have been performed successfully, your Ampler bike should now have a reliable motor support again.

If you hear creaking noises from the bottom bracket, we would first ask you totighten the pedals using the Allen key that was sent with the bike. Please also apply some multi-purpose grease to the thread. Then screw the pedals in by hand for a few turns, evenly. Once the first threads are engaged, use the Allen key through the crank arm and tighten the pedals firmly (35 Nm). Please also check whether the crank arms could be moving or shifting on the bottom bracket axle (the “bolt” to which the crank arms are attached). If this is the case, simply tighten the bolts using an 8 mm Allen key.If the noises persist, you can ask a professional local workshop to clean the bottom bracket. Please forward the following instructions to the workshop:

1. Remove the crank arms.
2. Continue as shown in this video until the point where the bottom bracket is removed from the frame (up to 4:30 min): https://youtu.be/GwByiIpYDC0. NB! The bottom bracket installed in the eccentric housing carries an important cable. During deinstallation, the eccentric housing may only be moved from the drive side and in a clockwise direction. Otherwise, the wiring may be damaged due to excessive twisting. 
3. Remove the bottom bracket from the eccentric and disassemble it.
4. Clean all contact surfaces. 
5. After removing dust, dirt, and debris, re-grease the contact parts with assembly grease.
6. When reinstalling, continue as shown in the video from 4:30 min.
7. Also make sure that the housing remains in its central position as a single unit and is not shifted to the left or right. Now tighten the two screws at the frame opening evenly to 10-12 Nm. 

NB! The Juna and Axel (Generation 2) models do not have an eccentric - in these models, the bottom bracket with sensor is mounted directly in the frame.To remove the sensor on these models, the Park Tool BBT-22 is required to loosen and later retighten the end cups. Loosen or remove the sensor by starting again from the drive side and turning clockwise.When reinstalling the sensor into the frame: first insert the non-drive side bearing cup into the frame (45 Nm) by tightening it against the direction of travel (when viewed from the left side: righty tight).Then insert the sensor (make sure the cable is correctly oriented) and install the other bearing cup as well. Tighten this again by turning against the direction of travel.

Fehlermeldungen/Error messages:

• Dafür tippe in der App auf: Mehr → Erweitert → Diagnosemetriken und Fehler prüfen.
• For this, select in the app: More → Advanced → Diagnostic metrics and Check errors.

Autorisierung/Authorization:

• Gehe in der App dazu auf: Mehr → Erweitert → Eigentumsübertragung
• More → Advanced→ Ownership transfer.

Abmelden/Log out of the app:

• Mehr → Dein Konto → Abmelden
• More → Your account → Log out

Firmware-Neustart/Firmware restart:

• Mehr → Systemwartung → Firmware neu starten
• More → System Maintenance → Firmware restart

Entkoppeln/Unpair bike:

• Mehr → Fahrrad wechseln
• More → Switch bike

Schlafmodus/Sleep mode: 

• Mehr → Systemwartung → Fahrrad in Ruhemodus versetzen
• More → System Maintenance → Sleep Mode

Werksreset/Factory Sleep:

• Mehr → Systemwartung → Auf Werkseinstellungen zurücksetzen
• More → System Maintenance → Factory reset