bottom bracket not flush / aligned ?

Went on a test ride on a beautiful old bike but noticed the bottom bracket doesn't seem to sit flush / aligned on the drive side. Looked fine on the other side, felt solid too. (Couldn't really inspect much further without taking off cranks which would've been weird on a test ride.) Does this look normal? Should I not buy this bike?

https://photos.app.goo.gl/iHJ6sv28wwUwrJ6Y7

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Looks cross threaded to me.

Probably messed up the bottom bracket shell threads, so risky buy in my opinion without taking it apart prior.

Can you even ride a cross threaded bb tho, without noticing weird sounds or play in the cranks?

I'm sure you can. Are you saying you don't think the cup is cross threaded?

The cup doesn't look parallel to the crank bolts, which appear to be parallel to the bottom bracket shell face. If I could draw a couple of lines, it would be pretty clear.

My other guess was that the bottom bracket shell was faced at an angle, but I don't think that's the case.

I would have thought a cross threaded cup would pop loose very quickly once it was being ridden. My initial thought is an improperly faced shell, although the geometry of the photo supports what tijs is saying...

Cup and spindle are definitely at an angle, pointing towards a cross threaded cup. You can see part of the spindle on one side, but not on the other.

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Can you just imagine persevering that long driving in a cross threaded cup though? As coils of swarf peel out.

thnx, I hear what you’re saying. I’m no mechanic but somehow wasn’t too worried about it: felt / sounded ok + as @fizzy.bleach points out: it does seem very stubborn to cross thread that far (it was put in and serviced by professionals?)
photo from less dramatic / clear angle:

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Can you just imagine persevering that long driving in a cross threaded cup though? As coils of swarf peel out.

There are some animals out there...

Depending on how much you like the bike and you can negotiate a suitable price to take into account the BB issue, it is fixable. Removing the BB cup and chasing the threads may fix it. Otherwise, a liner can be brazed into the BB shell and a new thread cut in it.

That's an old cup and cone BB, so that cup would have gone in independently (being the fixed, non adjustable, drive side cup) and there would be nothing other than the resistance to indicate that you were cross threading it (the resistance should have been enough but, you know, some people have fists of ham). If you tried that with a modern cartridge BB, the BB itself would be clearly off-line when you looked from the NDS and might even bind on the shell.

If you could find a cheap modern BB with steel cups, do you reckon it would be possible to wind the NDS cup all the way in first (beyond its normal position) and then use that as a guide to make sure that the DS cup went in straight? You'd need steel cups as you'd effectively be trying to recut the thread (or at least re-establish some sort of thread on the correct alignment through the mess of mangled shell and swarf). You could even file slots in the thread to create a ghetto tap and help it clear the swarf. If you weren't too fussy you could add a shedload of threadlock the the DS cup and then it would probably hold fine. Just a thought in case you want a cheap solution.

Id guess that its come loose over time and shifted diagonally under riding pressure. Seen a few old fixed cups do it. Can normally tell by giving a the further out end a tap with a dead blow mallet. 75% of the time it will straighten out then can be removed with less damage and will show the threads mostly intact. Run a tap through it and should be good to go. The other 25% of the time is as said above fitted wrong in which case can be more damage and money.

met with seller at bike shop today who’ll take it apart to assess, we’ll take it from there. thnx for advice, it helped me being a bit more patient.