Paint issue - is it corrosion or just a painting flaw?

[Clean39T]

Just found this rough looking spot on my Yamaguchi while giving it a good wipe down - anything to be concerned about?

https://uploads.tapatalk-cdn.com/20170416/ff92534e7f35e4e86a43a51681694a07.jpg

https://uploads.tapatalk-cdn.com/20170416/df9bcae05cd993e0b59a4f136edb8982.jpg


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[EricEstlund]

Pull out the seatpost and feel around in there/ shine a light down.

[Cicli]

Is it a repaint?
Looks like corrosion that has been painted over. Either that or poor prep for paint.

[Clean39T]

Pull out the seatpost and feel around in there/ shine a light down.

Perfectly smooth and nothing out of the ordinary from the inside.

[Clean39T]

Is it a repaint?
Looks like corrosion that has been painted over. Either that or poor prep for paint.

It's the original paint job. The frameset was built in 2009 and was framesaver'd, though it did live in the NE for those years. I can't find any other flaws and there was only minor rust dust on the fork steerer when assembling two months back..

If it's just some poor paint, that's cool. What would be a sign that it's corrosion? Would there be bubbles that could be "popped", vs. being hard?

[ultraman6970]

Almost 10 years, the paint is bubbling. It could be many things but my best guess is that the frame was not prep correctly and after 10 years the primer failed.

TO find out you have to sand it down to the metal. Mr Yamaguchi can tell you the color? maybe is a stock color and he can send you the ral# or the name of the paint and then you can repair it? Or send it back to him to get the paint fixed in that area?

[Peter P.]

Rust underneath would cause the paint to separate from the steel, bubble, then flake off. That's happened to me before.

Looks like it's a paint application flaw. Regardless of the cause, I wouldn't worry about it until you can pick at the paint and it flakes off. Then, if you're seriously interested in maintaining the frame, you can go for a proper repaint.

In the meantime, let me give you a tip from a career-long steel frame owner: After sweaty rides, wipe the frame down with a wet rag. Focus on locations were sweat usually collects such as the top tube, base of the head tube, and anywhere else you noticed rust on other frames you've owned. It will go a long way to preserving your frame.