The picture is very bad. As you found the crack, I guess you can see it from the outside. What do you mean by "internal"? Is it an endoscope picture? If so, the crack seems to go from the outside inwards, through the whole laminate.

Sorry for your friend, but you can say that a crack like this only happens through an external forces. Additionally, carbon composites have excellent alternating load propertys. If the frame made 2 years without getting this crack, it is extremely unlikely that it will get damaged by regular use.

I am pretty sure that something happens to this frame. Maybe an impact, maybe jamming or inappropriate clamping during transportation.

Pretty hard to determine based on that. It does look like the laminate has possibly been crushed inwards, but I'm no expert. It is also right next to a seam, which for me could indicate a manufacturing issue.

My gut response to that image based on my experience is that it was an external impact. but as I said, I'm no expert on laminate failure, so could be wrong.

You can see it externally. Factory is trying to refuse warranty so they came up with this internal pic saying that an external impact promoted the damage.
2 years of use and very mellow ride.

I don’t know why I can’t up load the pic but you can see it at the link below:

https://ytindustries-usa.zendesk.com/attachments/token/FY0Z4zqRfeZuNREp9Uw638I0Z/?name=inline-1383231139.png

how did he find the crack? was it an external crack and how old and what use has the frame undertaken?

Recently a friend of mine identified a crack on his bike frame.
He tried to solve it thru warranty but after tons of emails trying to prove that it was a manufacture issue, they came with a internal picture and said that the crack happened due to an external impact.
Based on only one pic....
I’ve attached the pic bellow. So I’m wondering, looking at it, can you assume it suffered an external impact?
If anyone can help us, please get back to me.
All the best.
Lucas.