Back in the day when I had a mini-bike it had split rim tubeless tires, so needless to say after a healthy amount of tread wear you got leaks.
Now being the idiot kid I was at the time I thought "Gas expands and so does stuff when it ignites!" I mentioned this "bright idea" later to a friend who had a few dirt bikes and had a Father that was a mechanic. He said "Yeah, they do that. You can do that, too."
So...anytime my mini-bikes tires would begin to get dodgy and soft I would peel back the tire and squirt in WD-40 and then ignite it and it would keep it full for about three days.
I played with fire far, far too much as a younger man. Looking back at how many hours I spent riding very poorly built and poorly maintained vehicle with combustible fuel (which I added "Octane Booster" to) next to a piping hot 10HP engine..I am surprised I didn't end up a statistic.
Would I do it all over again? Hell yeah.