General traffic on this road are: passenger cars, trucks and motorcycles. And by OSM definition "maxspeed = maximum legal speed limit for general traffic". So MAXimum legal speed limit for general traffic here is 90. Horses are forbidden to ride on high speed roads in Latvia. Also bicycles, electric scooters can not drive on these roads if there is a side walk near by and on this road - there is a side walk. Mopeds do not qualify as moped if ther max speed exceeds 45 km/h. So this sign also do not apply to them. If they exceed 45km/h they are qualified as motorcycles. The same goes to quats/tricycles - they fall under motorcycle category in this case and have to ride under 90km/h speed limit.
There are many analogical exception of this kind in all the baltics and they are marked as having 90km/h speed limit.

The problem for us is that we give car sharing passenger cars warning that they go over the OSM "maxspeed" limit and this is the only road that started to cause us problems and our clients get unnecessary warnings.

Can You please help us this this problem?

Here is the link from my previous message, but that road is not the same as here.

https://www.openstreetmap.org/edit#map=18/56.936185/24.132804