Crack or paint defect?

[dmwill]

I won't go into detail on brand yet.

Noticed what appears to be a hairline crack at the back of the head tube (between the top tube and down tube). Quite noticeable when running finger nail over it.

I've had a similar issue occur on the forks about 12 months ago - this was confirmed to be a paint crack by the manufacturer. Their short answer was "forks might have flexed causing the paint to crack". They still went above and beyond with warranty - getting them sent to the other side of Australia to get repainted by their approved painter and returned within a week.

Will be taking the bike into the shop next week for assessment, but keen to get any thoughts/second opinions.

[skom25]

In my opinion, it is scratch. Real crack will be more "open", especially if you are afraid that something is wrong with carbon. Edges are sharp and there is empty space in the middle.

Mark both ends with something (e.g. Tape) and check after some time, if it is longer than before.

[tarmackev]

Looks like a scratch to me also.

A very strange place for a crack, not really a stress point.

[eucalyptus]

I would say 100% a scratch.. Looks like something you could cause with lightly scratching using a key. It is too thin and not deep enough to be a crack. Also looking at the top of scratch, that line is super thin.

Actually zooming in, I don't think that scratch even touches the paint? It has only gone through the cleat coat hence the white line.

[skom25]

I don't think that scratch even touches the paint? It has only gone through the cleat coat hence the white line.

There is a simple method to check this. Pour out some water on scratch. If scratch dissapears, it is only clear coat. If not, base layer is also damaged.

[gorkypl]

A scratch, probably caused by a grain of sand during cleaning.

[AJS914]

I'd be embarrassed to take that into the bike store. What they said above - tiny hairline scratch. Plus, everything looks worse under macro photography.

Just hit it with some auto paint clear coat cleaner and it will dissappear. Just some wax might even do it.

[Catagory6]

here's a way to check if its a scratch

get a microfiber cloth and dampen it with water. then apply a dab of toothpaste, and rub it in to the cloth. then polish area.

if its a scratch, it will disappear without any evidence