Bosch Nyon: update the firmware (Flow, Wi-Fi or dealer)
BUI350 updates all components via eBike Flow; the BUI275 updates itself over Wi-Fi but its drive unit needs a dealer. Fifteen to thirty minutes.
Step by step
- BUI350: charge the battery, keep the bike on, open eBike Flow > Settings > your eBike > 'Updates' and install. Wait for the restart and the 'completed' message.
- BUI275: connect to Wi-Fi (Settings > Connections > Wi-Fi), then Settings > 'System settings' > 'Update' (or the update notification). The Nyon downloads and installs; keep it on the bike and switched on.
- Check versions: Settings > System settings > 'Info' (BUI350: also in eBike Flow).
- Drive unit and battery updates on the BUI275 are dealer-only with DiagnosticTool; on the BUI350 they go through the app.
- Afterwards, check language, units and brightness.
Tip: Do the update at home with the bike on the stand; a broken Bluetooth or Wi-Fi link mid-update is the main cause of a Nyon stuck on the boot logo.
Can't find it?
If no update is offered, update the app first; manufacturers release Bosch updates per model, so timing differs by brand. A Nyon stuck on the Bosch logo after an update is recovered by a dealer with DiagnosticTool.
Frequently asked
Can I update the BUI275 motor via Wi-Fi?
No, only the Nyon itself; drive unit and battery need a dealer.
How long does a BUI350 update take?
10 to 30 minutes depending on components.
Will an update delete my maps or routes?
No; maps and activities stay.
Manuals and video
- Bosch eBike Help Center: official error-code index
- Bosch eBike downloads: quick start guides and battery guide
- Bosch eBike dealer search (DiagnosticTool readout)
Videos found on YouTube and checked automatically; they are other people's work, not ours.
- How To | Update Nyon Bosch eBike Systems
Other Bosch Nyon guides
Bosch Nyon: change the display language (BUI350 and BUI275)Bosch Nyon: switch from mph to km/h (or km/h to mph)Bosch Nyon: set the time (usually automatic)Bosch Nyon: reset the trip distance and ride statisticsBosch Nyon: wheel circumference (dealer-set)Bosch Nyon: change assist modes and customise them (BUI350)Bosch Nyon: activate and use eBike LockBosch Nyon: set the display brightness and night modeBosch Nyon: pair with eBike Flow (BUI350) or eBike Connect (BUI275)Bosch Nyon: enable and use walk assistBosch Nyon: turn the lights on and off, automatic and always-on lights
Still stuck? Take a photo of the display and show it to a local e-bike workshop. Bring the bike's system name (e.g. Bosch Performance Line CX) and the exact code; that saves diagnostic time and money.