Bosch Purion: switch from mph to km/h (or km/h to mph)
You switch units in the Purion's own settings menu. About one minute, no dealer or app needed.
Step by step
- Switch the bike on with the power button on the Purion.
- Press and hold the − button for about 1 second until the settings menu opens.
- Press + or − to move through the items until you see 'km/mi' (older firmware may show 'Units').
- Press + to toggle between km and mi. Speed (km/h or mph), trip and total distance all follow this one setting.
- Press and hold − for about 1 second to leave the menu. The ride screen now shows km/h (or mph).
Can't find it?
If the settings menu does not open, you are probably holding the power or light button instead of −: on the Purion the − button is the lower of the two on the side of the unit. If 'km/mi' is missing, the unit is on very old firmware; a dealer can update it with DiagnosticTool.
Frequently asked
Does switching to mph change the 25 km/h cut-off?
No. Units only change what is displayed. The assistance cut-off is stored in the drive unit and can only be set by the manufacturer or a dealer.
My Purion still shows mph after a firmware update.
An update can reset the display to factory defaults. Open the settings menu (hold −) and set km/mi again; your total distance is kept.
Will the total distance be converted correctly?
Yes, the odometer is stored internally and simply displayed in the chosen unit.
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.
- Bosch Purion - change from mph to kph Electric Bike Team