Is this a crack

[Imlach]

Is this a crack?

Runs up the downtube slightly, slides around the weld of the BB and downtube weld, not very deep can just barely feel with my finger nail.

Opinions? Sorry for the bad photo but it's nearly impossible to see unless lit up another light

 

[27motorhead]

Could be?! Not helpful I know, but seen cracks like this before. Maybe get a greasy/dirty finger and rub all over the crack then use a cloth/rag to wipe clean which should make the “crack” more visible. Take the photo in natural light to help.

Also removal of BB would help.

Got a titanium Raleigh with a top tube / seat tube crack just like this. Hanging on the wall waiting for me to decide if I should get repaired or not...

 

[M_Chavez]

Does it creak?

Looks like it might be a crack...

Is this an old frame? I'd carefully pick the paint around it with a sharp stylus/old chisel to see if it goes into the steel.
Get a bucket for crying into.

 

[Imlach]

No creaking

Very hard to see it in natural light, going to try and remove some paint

 

[M_Chavez]

As much as it might hurt you to bastardize the paintwork, that won't be as painful as if the bb separates.

 

[Imlach]

Should I try to remove the paint throughout the whole length of the scratch/hopefully not crack or just a bit of it?

 

[Imlach]

Looks like it's not there on bare metal

 

[Mickeyspinn]

Looks like it's not there on bare metal

Get a willing helper stand on one pedal and push against saddle and bars....see if it moves?

 

[2manyoranges]

Sound can be quite important in such a context.

Get a 10mm-ish spanner or use the ‘wrong’ end of a metal handled pick and tap the tubes around the headtube. Tap close to the joints then tap progressively away for about 10cm. Log in your mind what this sounds like. Then do the same with the tube at the BB which you think is cracked. A cracked tube can sound very different - very dull and a sound which begins and ends very quickly. If the other tubes are sort of ‘ping ping‘ and the potentially cracked one is sort of ‘clack clack’ then yep you have a crack. I have seen engineers who listens to all sorts of things down special listening tubes - Ian Tyrell adjusts racing engines by listening down a pipe. It can tell you a lot….

 

[Mickeyspinn]

Sound can be quite important in such a context.

Get a 10mm-ish spanner or use the ‘wrong’ end of a metal handled pick and tap the tubes around the headtube. Tap close to the joints then tap progressively away for about 10cm. Log in your mind what this sounds like. Then do the same with the tube at the BB which you think is cracked. A cracked tube can sound very different - very dull and a sound which begins and ends very quickly. If the other tubes are sort of ‘ping ping‘ and the potentially cracked one is sort of ‘clack clack’ then yep you have a crack. I have seen engineers who listens to all sorts of things down special listening tubes - Ian Tyrell adjusts racing engines by listening down a pipe. It can tell you a lot….

True! I used to balance my twin carbs like that and diagnose which pesky tappet wasn't playing ball!