Road tubeless setup, and have been happy with it for several years. In the past year I have had a couple of my tires blister either on the centerline of the tread or just slightly off it. In one case it was just one blister, and in another I had eight (!) blisters on one tire. Nothing catastrophic happened and I replaced the tires both times. This occurred on a name-brand performance-level tire (not silly light, but still respectable) that I have been using for a couple years now without issue (700c x 25 on a wide rim that nets a true 28mm width). Both incidents were on the rear tire and the tire pressure was at a reasonable 82 psi (5.7 bar). Incidents have happened when tire was only 25% worn in one case and 50% worn in the other. I am not a heavyweight. I do corner a bit hard when the occasion presents itself (love the feeling of railing a corner at speed). A fellow rider using the same tire also had this happen once recently, which somewhat eliminates it being just me. I have had a flawless run with these tires for 3+ years before the recent incidents.

the blister

What causes this to happen, especially more than one time? A bad batch of tires? Hard cornering? Bad luck?

  • Any chance you used it on an indoor trainer where the drum rubs against the tire? May 17 at 18:47
  • @NoahSutherland nope, not this one. It is purely on the road. My old road bike is on the wheel-off smart trainer for a few years now. I could see that as a possible for a wheel-on trainer, especially with a lot of power being put down (not a problem I have). ;)
    – Ted Hohl
    May 17 at 19:43

2 Answers 2


This problem was not uncommon when tubeless was new, but this is the first case i've seen in a modern tyre.

In the early days this was thought to be due to Stans sealant containing ammonia and some sort of chemical reaction. However I think the case was actually that tyre manufacturers didn't have a robust manufacturing method for tubeless tyres.

More recently this is generally accepted as a manufacturing fault and distributors should exchange these for new tyres. The layers of tyre have delaminated and air is getting between them.


Manufacturing defect. The bond between the casing and tread has broken down, air is leaking though the casing and stuck under the outer lay.

I would look at taking back to place of purchase and see if you have a warranty claim.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.