COLBY (and a few others) make a tire air valve which can be installed from outside the wheel - and without breaking the tire bead.
My dealer tire tech messed up when installing my new Pirelli Angels by tearing the new valve stem (causing a slow leak) and by scratching the paint on my wheel.
Did some searching - and found I do not have to remove the wheel again, or break the bead and push a new valve stem in the very limited space of this thin tire on the small scooter. Amazon had a pair of these new brass valve stems to me in 48 hrs.
Installed DynaBeads in the tire before starting.
Cleaned the hole in the rim with Q-tips and alcohol.
Make certain the Colby valve stem is pushed all the way home - fully against the rim!
Tighten with 7/16th wrench while
applying pressure to keep the black base of the stem firmly against the rim!STOP tightening as soon as the whole valve begins to turn in the hole. Do not over-tighten. That will only crush and deform the sealing rubber parts!
Air it up ....and fingers crossed! (thumbs pressed)
I'll be checking the PSI tonight, and for the next few days.
If I didn't get it right- I've one more to try.
Stig
PS: I find long air valve stems a pain when checking or airing up - so I purchased the "short" Colby stems.