BB30 vs PF30: which one is yours?
BB30 and PF30 use the same 30 mm spindle, but they are not interchangeable. The difference is the frame shell: BB30 = 42 mm with the bearing pressed directly (against circlips); PF30 = 46 mm with the bearing inside cups. If your shell is 42 mm it's BB30; if it's 46 mm it's PF30.
It's the number-one press-fit confusion: because both use a 30 mm spindle, people think they're the same. They aren't, and fitting the wrong one means the part won't go in.
The difference in one sentence
Both come from the same idea (a stout 30 mm spindle for stiffness), but BB30 presses the bearing directly into a 42 mm shell, while PF30 puts it in cups inside a 46 mm shell. Those cups make PF30 forgive carbon tolerances better and creak less.
Comparison
How do I know which I have?
Measure the inner diameter of the frame shell: 42 mm = BB30; 46 mm = PF30. Both are usually 68 mm (road) or 73 mm (MTB). If you're not sure which spindle to fit, both accept 30 mm, SRAM DUB and Shimano 24 mm with the right cup or adapter. Still unsure which bottom bracket your bike has? Start with this guide.
Not sure if your frame is BB30 or PF30? Send us a photo of the shell: Message us on WhatsApp
Frequently asked questions
Are BB30 and PF30 the same?
No. BB30 = 42 mm shell with a direct bearing; PF30 = 46 mm shell with cups. They are not interchangeable.
Which one creaks less?
PF30, because the cup absorbs frame imperfections. The direct BB30 is more prone to creaking.
Can I convert one into the other?
A PF30 frame (46 mm) can be converted to threaded with a two-piece bottom bracket; a BB30 (42 mm) has fewer options. One does not transform directly into the other.