Old GT frame has been resurrected into ss and city duties, but now I've noticed a crack in the paintwork. In your vastly experienced opinions, is it the paint or the frame?

What's the best way to strip the paint to look at the metal?
Nitromors? Burner? Scraper?

Keep riding and see if it grows.

Looks like paint to me.

Paint does not just crack, that is on its way out, i've got almost identical pics from my old meta frames.

You dont need to scrape/burn/nitromors the paint off for a better look, that is a classic fatigue crack, right on the base of the weld.

How long have you had it? If its got warranty, send it back, if not keep an eye on it whilst you look for a new frame.

How long have you had it? If its got warranty, send it back, if not keep an eye on it whilst you look for a new frame.

No warranty AFAIK, unless GT have rolled out a new 15year warranty. It's had a good innings, so no tears here. 😀

Time for another new bike… 😆

I bet it's the paint only, mind you you seem to be looking for an excuse to buy a new bike…

Or maybe I don't trust you. 😆

I don't think I would have even noticed that – I certainly wouldn't be worrying about it, especially if you're not using it for mtb.

Ive had heaps of frames (for customers) replaced due to marks on the edges of welds exactly like this.

considering where this mark is,i wouldnt ride it.

just get some nitro on it, and see whats under there. It's white, so a touch up paint should look pretty good after.

Looks like it COULD be a crack, and when the headtube from my (very poorly welded) GT snapped off mid ride (jump), i broke my nose, and smashed my face up pretty good.

So, i would get the paint off and make sure. Aluminium give you absolutely NO warning before a high pitched 'schtiing' noise, and instant face-plant.

That's what I'm worried about lardman.

If that is a crack, it's gonna get a bit bigger before letting go, certainly on road stuff.

That is crack in the base of the weld. Anyone who says different is wrong. Given the material of the frame I'd be very cautious about using it.