There's still quite a few riders out there who keeps there's restricted. The speed reading normally stays correct if you leave it like that .....
I did try restricting my Kenevo down to 20kph in the interest of more range, it didn't work and wasn't fun.
Keep in mind the usual warnings about affecting your warranty if you override any fixed settings on the bike. Also keep in mind that you might no longer be legal. If you're not bothered too much about your warranty and ride on private ground, then search the forum for steps unlocker and stunlocker (it changed names because shimano blocked "steps"). If you use that (€30) you can change the location to US from EU and increase the limit to 32kph, which feels a lot more natural for most riding. This doesn't change the "wheel size" setting, so the speed display stays accurate.