Originally Posted by wmtire
That rubber is going to pop. Anyway, ya can safely deflate the tire?
The pic isn't real clear on my monitor but that looks like a scuff mark on the rim lip, where the bubble is. This kind of bubble is commonly caused by a shock pinch, due to hitting potholes, RR tracks, or curbs. (or what we call everyday driving)
P.S. Even when you deflate the tire, the bubble is going to most likely remain for awhile........but won't have the backup force of a fully inflated tire. You most likely have a small hole in your inner liner that can be caused by a puncture near the edge of the tread but is commonly caused by an inner rim lip pinching it when hitting a pot hole/curbs/rr tracks and/or the shock of the casing cords breaking from same.....that is letting the air inside the tire into the outer rubber casing. The pressure will eventually overcome the casing and it will pop.
When you get the tire dismounted off of the wheel, you probably can look inside with a good light, and may have to flex the sidewall at the bubble point,,,but you should be able to find a small cut in the inside liner.
I'm with him.
It's on the inside, so you're reasonably safe. Pull the valve cap and use a small screwdriver to push the valve core and let the pressure out of the tire. If that blows it could blow violently and bend the rim or damage the trailer depending on what's in it's way.
Like WM said, that's a pinch injury. Potholes, debris in the road usually cause the inside ones, outside ones are usually curb strikes. It could also be a factory defect within the tire, since you just got it you might be able to get it warrantied.
But please don't get under it again, there's an amazing amount of energy inside a fully inflated tire.