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When I try to inflate a tubeless tire which I have just installed, it may or may not work: some tires leave a wide gap near the rim through which the air escapes without doing anything useful. This is solved by having a powerful pump, which blows so much air that it doesn't have time to escape.

Typically, this is done in a bike-shop which has readily-available compressed air and powerful pumps. But some people make DIY air containers, which you could slowly fill with a regular pump, and then open a valve, which sends a blast of air into the tire, inflating it.

I have a different idea: fill the air inside the tire with flammable vapor (use maybe acetone or alcohol), and light it with some fuse. I saw videos where they do it for car tires, so it should work for bicycles, in principle. What's more, it's more useful for bicycles than for cars, because it's easy to remove a bad tire without specialized tools. I imagine such a technique could be useful for replacing a tire in the field. An alternative would be using a spare tube (which I do all the time).

Has anyone done it (even just for fun)? Is anyone doing it routinely?

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I have done this. Not for clicks but because I was in a pinch.

I succeeded in mounting one 5" fat bike tire (on an 80mm alloy rim) that way. Worked beautifully without issues the whole winter. The second tire was irreversibly damaged in the attempt.

While it was unreasonably satisfying mounting a tire like that I definitely wouldn't recommend it.

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You might see this on a viral video, often with large-volume off-road automotive tyres used on 4WD vehicles. 4WD have many times more internal volume than a car tyre, let alone a bicycle tyre and the tolerance for error is larger.

I suspect that to get sufficient volatile vapours inside your tyre such that it can burn rapidly, you'd risk having too much or not enough fuel, or air.

And if you got the small amount of mix to burn, it would not likely produce enough heat and vapour to fill your tyre and seat it reliably.

Your real resorts for a tubeless tyre that won't seat, are some zip-ties or string to try and compress the tyre so it forces the bead wide, or fit a boring traditional butyl rubber inner-tube and inflate like cyclists have for many decades.


I've done some off-road driving, and the first action if a tyre lost its bead would be to inflate it with a rope or tiedown around the middle of the tread. This compresses the flat part, and pushes the bead out till it touches and can form a seal.
The second solution is to swap the wheel for your spare.
If you're down to your last-resorts then you've already failed to prepare and noone else on the trip has a matching bolt hole pattern on their spare wheel, then you're getting into the risky stuff like fire.

The risks are doing further damage and ending up worse off. Fire can ignite other things - imagine if the vehicle's fuel tank was leaking, or there's a buildup of grease in the area which starts acting like a candle.
The shock of rapid burning could tear and throw the tyre in a random direction causing injury to an onlooker of yourself. The rim itself may suffer damage. The vehicle might fall off the jack, etc.


In short, its too risky and the consequences far outweigh any benefits. Unless you're doing it in your backyard for click-videos, its better to go prepared. Everyone riding Tubeless should carry a Tube, or be prepared to walk out.

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    I'm curious as well, assuming there's no immediate failure or catastrophic failure to to the combustion-inflation method, isn't there a risk from long term exposure of tire rubber to gasoline if the combustion isn't complete (i.e. if there's a residual amount of gasoline left on or inside the tire)? Some Googling suggests that "regular" tire rubber can degrade from exposure to gasoline and that rubber components expected to come in regular contact with gasoline in a vehicle setting use special types of rubber that resist these degrading effects.
    – SSilk
    Commented May 3, 2023 at 11:29
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    @SSilk good point - fuels and oils can degrade the butyl rubber over time too. Same goes for combustion gasses that might end up inside the tyre.
    – Criggie
    Commented May 3, 2023 at 19:25
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    Seen this done several times with dump truck tires on steel rims. Starting fluid (heptane + ether) is the explosive vapor used to blast-seat the bead. Problem one is the relatively low air volume of a bike tire. The expansion of gasses from the explosion would cause a huge overpressure spike damaging rim, tire or both. Second the majority of bike rims are made from aluminum alloy, followed by carbon fiber. Materials ill-equipped to handle the forces involved, and even if they could, what of the joint in the alloy rim? And doing that to a carbon rim? Nuts. Steel rims are cheap and jointed.
    – Jeff
    Commented May 4, 2023 at 11:10

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