Originally Posted by
hotbike
I am looking online for bottom bracket bearings, and they’re all Sealed .
Nope, I'm looking at a ton of 9-bearing 1/4" crown assemblies specific of bikes right now on amazon.
The LBS will have loads of them as they are very common for big box store bikes.
Originally Posted by
hotbike
I really think the factories, the Chinese ball bearing plants, are producing a metric equivalent, and there’s no changing that fact.
Nope, the exact size is required for the right application, there is no substitute. SAE bearings, nuts, bolts, are still manufactured and regularly used in motorcycles and automotive.