Originally Posted by
Deontologist
It looks almost like you scraped the paint off judging from your picture. I don't really see a dent. I don't see any sort of depression.
I would just ride it and keep an eye on it, because that's near the welds and it might be in the heat affected zone. These zones are generally a bit weaker than the non heat affected zones.
Just be glad that you didn't hit the top tube. That part is supposedly very fragile - fragile enough to be dented by a knee while pedaling. Some people report they can feel the top tube flex when squeezing it.
What I see is a tube that was slightly compressed and the paint flaked away from the compressed point. The dent, if I'm seeing it correctly, is a flattened area less than the tube diameter in length and of a depth that hardly changes the overall structure of the area.
OP, I didn't say why I think you're okay. It wasn't a flip comment. I just don't see how your dent can possibly impact durability in the short or long term. It may be in a heat treated region of the tube set but it a region that is buttressed by the juncture of four tubes and that tends to strengthen/support, not weaken, the overall structural properties of the metal in that area. Said another way, if you want to split a log, hit it where the grain is clean, not in a region blooming with knots. There's no way your frame is going to split through that tangle of knots.