Question about steel integrity
 

Okay folks I have a question about this vintage Pogliaghi frame I'm looking to buy. So I am corresponding with this guy who owns a bike shop and over the years has taken in quite a few vintage bikes on trade. One such bike is a late 70s early 80s Pogliaghi. It is a sante pogliaghi as it is stamped JSM with the serial number. Anyways the guy is real honest and in one of the pics he sent me of the frame there are 3 tiny lines in the paint. He says they are from the frame at one time being bent and bent back into place. My question is how big of a deal is this? Obviously this will effect the value of the bike however I'm mostly concerned about the structural integrity of it. Will this effect the ride or the durability of the frame? I have always wanted a Pogliaghi for my personal collection. This isn't something I would resale however I would like to ride it. What do you guys think? Thank you as always!

I have steered clear of bikes that have suffered a crash, usually showing stress just behind the lower head lug.
Reason is the discount offered is not equal to the value going forward.
Not about a structural concern.

Pass. See if he has any uncrashed frames.

Where is the damage? I consider bikes with the telltale bulge under the DT behind the head lug to be suitable only as garbage or wall decor. It might not break, but they can and do break if damaged like that. Not worth the risk to your neck.

I might consider a bike with a bent and repaired stay as a commuter or something, but only if it is sold at a huge discount.

I agree with the above. I wouldn't buy a bent frame. But you haven't told us where it was bent; maybe it's not so bad as all that.

I have ridden two early 1960s frames which had been bent back and straightened -- a plain gauge carbon steel Bianchi and a a butted 531 Capo. Both eventually failed near the front of the downtube, where it had been bent, but I did get some good use out of each one before the telltale crack began to form. I never felt that my safety was compromised. Having said that, I doubt I would pay much for a frame which had been restraightened.

No pictures?
I am currently commuting on a vintage frame (PX-10) that was straightened. There is still a slight bulge/crumple under the DT and TT. My LBS, who has all the frame tools and straightening stuff and is adept at using it says it retains 95% of its original strength.

You know, I think that's a totally fair point. And I don't know what's the correct answer.

My brother once had a bike he loved. It was a Miyata. I have no idea what model, but it was red and it was his favorite bike. Alas one day a DC taxi stopped right in front of him, he hit, direct hit. He cursed, went around the taxi and rode on... And only later discovered that he'd bent his frame. Minor bend; he could still ride the bike, but it didn't feel right. So he had the mechanic at the local bike shop straighten it.

But it still didn't feel right. He sold it. The bike has lost it magic.

I front-ended a Motobecane GJ (Vitus 172?) and bent the down tube slightly. I rode it for approximately 10,000 miles after that and then the down tube cracked just behind the head lug. I wasn't a catastrophic failure. I saw the crack early.