Before the emergence of BB30, the first version of the bottom bracket evolved into many different historical and regional models. Generally, they all have unambiguous names, such as one-piece crack bottom bracket, Japanese spindle and cups, square taper, Octalink, 10T or 12T splined bottom bracket, and BSA threaded bottom bracket.
And then, Cannondale launched the BB30. In the name ‘BB30’, ‘30’ refers to that it is suitable for 30mm spindles. This is relatively easy to understand. But afterward, the naming rules for the bottom brackets became very chaotic.
There are several evolved versions of BB30 direct fit. They are BB30A direct fit, BB30A-83 direct fit, and BBright direct fit. They were designed to adapt to different shell widths. But they are the same thing. Why do they have different and irregular names? That’s so confusing.
The frame shell corresponding to the BB30 press-fit standard is a press press-fit shell with 42mm shell ID. Any bottom bracket that fits the BB shell mentioned above can be named the BB30 bottom bracket. After that, there were many versions of the BB30 press fit. They have the same appearance, only using sealed bearings with different inner diameters. They support different spindle diameters, such as 24mm Shimano spindle, 22-24mm GXP spindle, and 28.99mm DUB spindle. But BB30 is their common name. If riders want to buy a bottom bracket on Amazon that can be pressed into a 42mm bottom bracket shell and works with a 29mm OD DUB spindle, most people don’t know what keywords to search for. BB30 DUB? Sorry, I don’t know.
The problem here is that the current bottom bracket standard and type name do not include a description of the outer diameter of the spindle, nor does it include a description of the shell width. We need to fix this! If I want to buy a BB30 press fit for road bikes, I don’t know whether should I search for BB30-68 or BB30 road. I can only search for BB30 and manually filter in the search results. This is very inconvenient. The bicycle bottom bracket industry does not have a unified rule for this.
Apart from the two issues mentioned above, the current naming rules are completely irregular. We can see these model names such as BB30, PF42, BB90, BB95, BB30A, BB30A-83, BBright direct fit, BBright press fit, BBright for 46mm shell, PF30, PF46, OSBB, BB86, BB92, BB107, BB132, SHIMANO PRESS-FIT, PF24, PF30A, PF30AI, BB386EVO. If we have not systematically learned these names, it is difficult for us to judge the specifications of a product solely based on these names. This is very unfriendly for newcomers.
I know I am nobody, but SUMLON is advocating for all participants in the bottom bracket industry that it would be better if we could work together to unify the type name of the bottom brackets for users. The new naming rule allows riders to determine what kind of new bottom bracket they need based on broken bottom brackets or even just the bottom bracket shell.
SUMLON suggests dividing the type name into 5 parts:
1. Cups specification: The way to connect the bottom bracket and bottom bracket shell: DF (direct fit), PF (pressure fit), and TF (thread fit).
2. Bottom bracket shell ID: The inner diameter of the bottom bracket shell.
3. Spindle specification: Spindle outer diameter, which may include GXP (22/24), SHIMANO 24mm, SRAM GXP 28.99 mm, and 30mm.
4. Bottom bracket shell width: The width of the bottom bracket shell. If BB can be used within a range of five ways with different widths, the applicable shell width range should be used, and/should be used between two numbers to indicate the front and back ranges, such as 86/92.
5. Bearings specification: Optionally add I or E at the end. I (internal bearings) and E (external bearings).
Under this naming rule, BB30 and its subsequent bottom brackets can have unambiguous names. The following is a list of new names for some bottom bracket models after using the new naming rule.
All bottom brackets can be renamed according to this naming rule. The new naming rule ensures that even beginners can quickly find the model they need.
