>>If there are no cutouts in
>>the shell, will stowaway water not sit at the base and still cause
>>deterioration anyway? Is there a prevalence of non-cut out shells
corroding
>>under normal all weather use?
I really don't know... I have seen a few rusty bottom brackets, so offhand I'd say, yeah, there's a problem with solid shells... but I haven't taken apart enough old bikes with non-cutout shells to tell for sure. Any bike shop mechanics out there that want to share their experience? I rode a PX-10 for 30 years that had a solid shell, but the serial number plate was attached with two tiny aluminum rivets that were loose enough to allow water to drain around them. My head tube had a wooden plug which I removed after two years when I noticed some rust. No more rust after that.
One thing I did not know until a few years ago (which is probably old news to everyone on this list) is that even when a tube's interior is completely protected from the elements (like a seatstay) there will still be condensation inside from changes in temperature, like when you bring your bike in and out of doors. So that's one reason for those tiny holes an inch or so above the rear dropouts (and I guess they're also needed during frame assembly; I imagine the change in interior air volume during brazing would have an adverse effect on the joint if there was no other way for air to escape).
The advice I got, from folks on this list as well as some local vintage bike owners, is that even though the holes give the moisture an escape route, it is still advisable to spray some WD-40 or Framesaver in those holes and shake it around to coat the inside of the tubes. And repeat the process for the rest of the tubes on the bike as well.
So now I feel pretty dumb because I thought I was taking great care of my bike all those years.
Bob Hovey
Columbus, GA