Every tire video starts (more or less) the same way: someone squirts a bit of starting fluid or another flammable aerosol into a tire (read: cover, rubber, or gum), creates a small fuse by spraying the surface, brings a flame close, and boom! The tire ends up perfectly seated on its rim. Sometimes it takes more than one attempt, but generally it works pretty well, even when seating large tires. Why does it happen?
Failures of some tires can be truly spectacular. There are dozens of factors that sooner or later lead to their collapse, which manifest even under good road conditions.
Anyone who has witnessed the replacement and installation of a new tire knows it takes a few seconds with the right tools, unless we are forced to improvise and do it ourselves.
However, a series of YouTube videos shows us that some people are using nothing less than fire and not-so-controlled explosions to seat tire beads. What kind of sorcery is this?
The Old Technique Behind the Viral Videos
In reality, it is an old technique, revived by the visual impact and the virality of the videos. As soon as it's installed, the tire floats on the rim, and we need (loosely speaking) its wires to stick to the sides.
It's supposed that normal inflation pressure is enough to seat the tire, but if there's no inflator or high-pressure source at hand, the idea is to fill the inside of the tire with some flammable aerosol liquid, and bring some fire near.
The gases associated with the explosion try to escape at high speed, forcing the tire to expand until it hits the sides of the rim. In most videos we see them inflating the tire immediately after the explosion, because it's very likely to try to return to its previous position... and the compressed air helps put out the fire.
Now, the technique can be useful in an emergency, however, some videos show well-equipped shops applying it. Why? Apparently, the desire to stretch tires has become popular among enthusiasts, meaning making the tire fit a wider rim than it's supposed to.
Personally, I don't really like the strategy of deforming tires purely by explosion, but the question is, what alternatives are there? On one hand, there are rubber tubes that are very easy to use, and on the other, the equivalent of a high-pressure bazooka. One more curiosity, at least until the tire of the future becomes a reality.
