Originally Posted by justpoet

If racing, I would agree. If bashing or speed runs, not so much.
I've seen duct tape used on the inside to help hold it, but eventually it gives. On hard and large knob tires I've seen fishing line used on the outside between the knobs, but that just seems like a recipe for disaster to me. None of those are considered legal for racing last time people I know were asking, but generally the best place to ask about stopping ballooning will probably be speed run forums.