Friction or normal behaviour?

When I push my 27.5" muni and lift it up the ground to see the wheel spinning, it spins on for a little bit, but not very long. Is this normal unicycle behaviour or might there be friction in the hub? I do not hear any strange sounds coming from the unicycle.

Your bearing caps may be on too tight.

Yes, I had tightened them firmly. Loosening them helped!