This post will give a short overview (list) of threadless (press fit) BB standards. For each BB standard, there is an overview intersection of the BB cartridge and frame’s BB shell where BB is inserted, followed by its dimensions. Look here for an explanation of all the different BB standards.
1. BB30
- Shell width: 68 mm for road, 73 mm for MTB.
- Shell inner diameter (Shell ID from now on): 42 mm. BB30 bearings have the same, matching outer diameter of 42 mm.
- Bearings press directly into the frame and stop at snap rings inside the BB shell. BB shell has snap ring groove at each side.
- Designed for BB30 cranksets with spindle diameter of 30 mm. With use of adapters, cranksets with 24 mm spindle can be used (like Hollowtech II).
2. PF30 (PressFit 30)
- Shell width: 68 mm for road, 73 mm for MTB.
- Shell ID: 46 mm.
- PF30 uses the same bearings as BB30, with ID of 30 mm for spindles with a 30 mm diameter. The difference is that PF30 bearings are first pressed into plastic cups that are then pressed into the frame.
- Designed for PF30 cranksets with spindle diameter of 30 mm. With use of adapters, cranksets with 24 mm spindle can be used.
3. BB86/92
- Shell width: 86.5 mm for road, 92 mm for MTB.
- Shell ID: 41 mm.
- Bearings are first pressed into plastic cups that are then pressed into the frame. The shell has a stepped profile, but there are no snap rings.
- Designed for cranksets with spindle diameter of 24 mm, originally intended for external threaded cups, like Hollowtech II.
4. BB90/95
- Used almost exclusively on Trek bicycles.
- Shell width: 90.5 mm for road, 95.5 mm for MTB.
- Shell ID: 37 mm.
- Bearings are pressed directly into the frame. They stop at a raised step inside the frame BB shell bore. No snap rings used like on BB30.
- Designed for cranksets with spindle diameter of 24 mm, originally intended for external threaded cups.
5. BBright Direct Fit
- Used exclusively on Cervelo bicycles.
- Shell width: 79 mm (road standard only).
- Shell ID: 42 mm.
- BBright Direct Fit is a variant of BB30 bearings, with a wider shell and asymmetrically placed bearings (left one is moved by 11 mm more to the outside). Bearings press directly into the frame and stop at snap rings inside the BB shell.
- Although it uses BB30 bearings, the shell is wider so it requires a BBrigh crankset with a longer spindle.
6. BBright Press Fit
- Used exclusively on Cervelo bicycles.
- Shell width: 79 mm (road standard only).
- Shell ID: 46 mm.
- BBright Press Fit is a variant of BB30 bearings, with a wider shell and asymmetrically placed bearings (left one is moved by 11 mm more to the outside). Bearings are first pressed into plastic cups that are then pressed into the frame.
- Although it uses BB30 bearings, the shell is wider so it requires a BBrigh crankset with a longer spindle.
7. 386EVO
- Shell width: 86.5 mm (road standard only).
- Shell ID: 46 mm.
- 386EVO is a variant of PF30 standard with a wider shell. Bearings are first pressed into plastic cups that are then pressed into the frame. Shell bore is smooth, and the outer (wider) lip of cups holding the bearings contacts the outside of the shell, keeping the bearings from sliding deeper into the shell.
- Although it uses PF30 cups, the shell is wider so it requires a 386EVO crankset with a longer spindle.
8. Table – overview of threadless BB standards
| Standard | Shell width | Shell ID | Snap ring | Cups or direct mount | Spindle diameter |
| BB30 | 68 / 73 mm | 42 mm | yes | direct | 30 mm |
| PF30 | 68 / 73 mm | 46 mm | no | cups | 30 mm |
| BB86/92 | 86.5 / 92 mm | 41 mm | no | cups | 24 mm |
| BB90/95 | 90.5 / 95.5 mm | 37 mm | no | direct | 24 mm |
| BBright Direct Fit | 79 mm | 42 mm | yes | direct | 30 mm |
| BBright Press Fit | 79 mm | 46 mm | yes | cups | 30 mm |
| 386 EVO | 86.5 mm | 46 mm | no | cups | 30 mm |