Road Cycling - first flat - blowout - kapow

I used to ride way back when, but tubes were not pumped up to 120psi. I was riding along today (on a new conti ultralight tube) and kapow - blew the tire off the rim. Split the tube along a 3 inch gash. I am sure glad I wasn't doing 35 downhill when it happened.

Did I do that? Was it a pinch flat or just one of those things?

Sounds like a pinch.

I've had the same thing happen. Pinched a new tube and didn't notice until a couple miles from the house when I heard a bang.

I used to ride way back when, but tubes were not pumped up to 120psi. I was riding along today (on a new conti ultralight tube) and kapow - blew the tire off the rim. Split the tube along a 3 inch gash. I am sure glad I wasn't doing 35 downhill when it happened.

Did I do that? Was it a pinch flat or just one of those things?

In my experience, pinch flats don't cause a 3 inch gash. Whenever I've had pinch flats, there are two holes on the tube that look like a snake bite.

My vote is "just one of those things".

talc powder on new tube

Ultra light tubes are just not worth it, IME. They anger the tire gods too much. I'm using all mine up and going back to a slightly heavier, but sturdier tube.

In my experience, a blowout like that is usually caused by either the tire seeding on the tube, or a tube that was super twisted when put inside the tire.

what does seeding on the tube mean?

Install error ... Tube was not in the casing but "pinched" under / beside it.

NOT a "pinch-flat" aka : "snake bite"

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well i installed it, ran my way around both sides looking for tube not under tire, partially lnflated it, checked it, bounced it some, deflated, and then fully inflated.

I put the replacement in the same way.... hopefully right this time :-)