If the valve stem looks like it has a grommet around it on the rim,
it's likely tubeless. If it looks like the stem sticks right thru the
rim, then it has a tube. However... several articles indicate
a sound reasoning for Tubeless construction. This is prevention
of blow-outs. As the air pressure get reduced, it finally breaks the bead
and the air slowly bleeds off.
In my experience, scooter tires can bleed off in certain temperatures overnight
(usually cold). If you just push the bike, you can notice that it's difficult. About 2
months ago this happened to me. Rode the 10 miles to work. Knew something
didn't feel right, but just kept going. At 7 miles, the back end started to sway,
At eight miles all the air was gone and there was no steering. Also was dark
and 5:00 am. The tire had spun on the rim and shreaded the bead, so it cost
$100 for a new one. I now have a plastic mallet and I hit both tires to check for the full tire sound.