The non-drive side of the bottom bracket took multiple days of soaking with pb blaster and heat to release. I have done the same with the drive side, but do not want to go further until I confirm the thread direction. Any help is greatly appreciated!!!
ps please don’t judge me too hard - I run a hardware store in my little hometown and wrenching is not a full-time profession. The grease in this bike is probably 50 years old and I am fully aware that heat damages paint. From the swamps of northeast North Carolina, thank you for the advice in advance! -Stu
With a near 70mm shell it’s likely Italian. Clean the goop out of the BB shell and determine if the fixed cup is left or right handed. You can tell by examining the thread cut. Italian is as you know I think, RH on both cups.
Not sure if you’ve already addressed/tried this but as Scott noted, the thread direction will tell you if it’s Italian. In Italian BBs both the drive and non-driveside cups tighten clockwise and loosen counterclockwise. That’s the only threaded BB design that does this. So assuming the threads at the outside of the shell at least are not so toast that you can get a cup started, if you try to thread it on clockwise and it goes, voila you have an Italian-thread BB shell.
Another clear tell is if there are any markings on those BB cups. Any Italian-thread BB is 36x24 and should be marked as such.
Joe and Scott and Petri (and Sheldon), thank you for your comments. They have been helpful in letting me know I am on the right track but still missing the definitive answer. I guess I am looking for confirmation that the non-drive side bearing cup fits the “36mm” diameter spec for Italian bottom brackets that I read about on the internet.
Unless there is a more exact answer that confirms the diameter of the non-drive cup bearing is Italian in size, I will let Father Time work his magic with more penetrating oil and keep trying to loosen it as a right hand thread very carefully. The lack of drive side markings, along with the fact that the cranks are French with BSA pedals, leads me to continue with caution.
My ample scraping of the threads with a pick, along with many measurements of the department store bikes I have available to me, remain inconclusive at this moment. I am not about to take apart my personal bikes to attempt a bottom bracket swap but that suggestion, Petri, is a good one if the resources allowed. Thanks, all!
Nope, French threaded bbs also tighten clockwise on both sides. He also has just the non driveside cup out and every bb tightens clockwise on that side…
Ime French BBs are very rare but not impossible. If you have access to either a metric or Imperial tpi gauge you can test that as well. Italian is 24tpi and French is 25.4tpi. close but with a proper gauge you can tell the difference.
I was on my local group ride yesterday and a fellow told me to call Cycle Classics in Portsmouth, Virginia (USA). After a quick call and photos text, Lyle confirmed that it was, in fact, Italian (confirming my suspicions). Armed with that belief, I heated the bottom bracket area up from inside the non-drive side… and with persuasion in the correct direction… whah-lah! Huzzah! Caper closed.
Ergo: If the non-drive side cup measures 36mm from edge of thread to edge of thread, along with the 70mm bottom bracket and Italian country of origin, that should be enough to try “lefty-loosey.” It worked for me, anyways.
