To clear up a little confusion (or maybe add to it) Ashtabula was a manufacturer, not a type of crank despite what wikipedia says. They were the best of the best and were mainly a supplier to Schwinn. They are basically unbreakable.
When I said there were 2 categories, Shcwinn and everyone else, I was referring to Chicago USA made Schwinns with (usually) Ashtabula-made cranks in them. I would suspect that newer Schwinns made by others after the factory closed would probably not have a proprietary Schwinn-threaded crank in them.
If you get a crank out of an old USA Schwinn it will be an unbreakable piece, but you will have to change your bearing set (all of it).
The trouble with the "everything else" category is that it might be every bit as good as USA Schwinn. Plenty of the stuff we see on this site is. Heck, even Ashtabula themselves made some cranks with the "everything else" threads on them during the early BMX era. On the other hand, you might wind up with something out of an 80s department store bike that is almost as soft as lead. It is so hard to tell from pictures exactly what you are getting.
Speaking of soft as lead, In about 81 I got an new trail cruiser made by one of those companies that makes department store bikes. The crank broke off at the pedal hole on the first day I had it. I put a real Ashtabula BMX crank and some Schwinn bearings in it and never looked back. I only bring this up because that pedal hole is a highly stressed area, and I don't think it would be a good idea to bore it out to 3/4".
When I said there were 2 categories, Shcwinn and everyone else, I was referring to Chicago USA made Schwinns with (usually) Ashtabula-made cranks in them. I would suspect that newer Schwinns made by others after the factory closed would probably not have a proprietary Schwinn-threaded crank in them.
If you get a crank out of an old USA Schwinn it will be an unbreakable piece, but you will have to change your bearing set (all of it).
The trouble with the "everything else" category is that it might be every bit as good as USA Schwinn. Plenty of the stuff we see on this site is. Heck, even Ashtabula themselves made some cranks with the "everything else" threads on them during the early BMX era. On the other hand, you might wind up with something out of an 80s department store bike that is almost as soft as lead. It is so hard to tell from pictures exactly what you are getting.
Speaking of soft as lead, In about 81 I got an new trail cruiser made by one of those companies that makes department store bikes. The crank broke off at the pedal hole on the first day I had it. I put a real Ashtabula BMX crank and some Schwinn bearings in it and never looked back. I only bring this up because that pedal hole is a highly stressed area, and I don't think it would be a good idea to bore it out to 3/4".
