with 3M double sided tapered (VHB Tape 5952F)
Here you have the ebay link with pictures in case you are interested.
https://www.ebay.es/itm/N-6-Soportes-para-display-ebike-Bosch-Nyon-al-cuadro-/254925024547?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l6249&mkrid=1185-127638-7840-0