【PIT TIPS】The Mechanic Saw It!! The Power of Tire Sealant

One evening, a young customer of ours visited the shop.
He said, "My tire burst on the gravel, so I need to replace it."
He is a cyclist who rides a gravel bike with 650x47b semi-off-road tires, hitting 150–200km on weekends regardless of whether it's on or off-road.
While he may not have much mechanical knowledge, he is extremely sensitive to changes in riding feel, whether it's from adjusting his riding position, changing parts, or experiencing mechanical trouble.

The bike he rides is set up with tubeless-ready tires in pursuit of weight reduction and ride comfort.
(For more on tubeless-ready tires, click here: "【PIT TIPS】Which One is Ready? – The Differences Between Tubeless and Tubeless Ready –")

The tire he burst this time was the front one; it was gashed deeply on the sidewall, possibly from a rock or something similar, making it irreparable. Since his rear tire was also wearing down, we ended up replacing both the front and rear tires.

The work went smoothly. After finishing the front tire replacement, I moved on to the rear tire.
While removing the tire, cleaning the sealant off the rim, and washing the tire itself, I made a discovery.

Ta-da!!

It was a fragment of something that looked like a stake, still stuck in the tire.

The tire that burst was the front one, and the rear tire was supposed to be fine, other than being worn down.
Normally, if something of this size remained embedded in a tire, the air pressure would drop instantly, making it impossible to keep riding.
Yet, what allowed him not only to keep riding but to do so without even tipping off a rider so sensitive to their riding feel?

It was the tire sealant.

Tubeless-ready tires are filled with a sealant liquid that instantly plugs holes.
That liquid had coated the puncture and the object like a membrane, preventing air from leaking.

What’s truly amazing is that it sealed the hole so quickly that even a rider sensitive to riding feel didn’t notice.
As he put it, "I wonder when that got stuck in there?"
Furthermore, since he had no idea when it happened, it’s possible it had been stuck there for a very long time.

As bike gear goes, nothing is foolproof, and it might be too much to expect a perfect result for every single puncture.
However, this time, the "sealant" did a fantastic job.

I’m glad he was using sealant.
You rarely get to see "sealant" in action, but seeing it like this, I have to take my hat off to how important it is.

For those of you using tubeless-ready, and of course for those of you using tubeless as well, please make sure to use tire sealant just in case.