Originally Posted by merziac

Could it actually be a 70mm bb, wouldn't think so by 89 however it may be possible and may or may not help explain your dilemma. Do you have a cup and cone bb to try in it just to see? I would also scrutinize the bb with the calipers if they are deep enough to go across both sides, check several different axises, may not be square but might be 70mm. I would make thread chaser out of an expendable cup if you have one, clean the threads with a right angle pick and then carefully run the chaser to see what happens.