Non-Threaded Bottom Bracket: How to Pick the Right Fit
By Eighth Generation | Authentically Native Designed | Wool Blankets | Published: 2026-11-04
Category: Osto-oppaat
Learn how to match a press-fit bottom bracket to your frame's shell width and inner diameter, and when a dual-row bearing design like the e*thirteen BB92 makes sense.
Quick answer
Buy a non-threaded bottom bracket by matching three numbers first: your frame's press-fit shell inner diameter (commonly 41mm), the shell width (BB89.5, BB92, BB107 or BB121), and your crank spindle diameter (30mm for e*thirteen cranks). If all three line up, the e*thirteen BB92 is a strong option because its dual-row bearings pack more support into a narrow shell.
Why shell width and diameter decide the purchase
A non-threaded bottom bracket is held in the frame by interference fit, not threads, so there is no adjustment for a wrong shell size. The shell inner diameter must match the bearing cup outside diameter, and the shell width must match the bearing spacing the bottom bracket was built for. Measure both before shopping; frame model names alone are not reliable because the same model can ship with different press-fit standards.
The e*thirteen BB92 illustrates the point: it is listed for 41mm ID press-fit frames and BB89.5, BB92, BB107 or BB121 shells. That range covers several widths, but the crank interface is fixed at 30mm spindle e*thirteen cranks. A 24mm spindle crank will not fit, no matter how well the shell matches.
The trade-off: narrow shells and bearing room
Narrow press-fit shells leave little room for bearings, which is why some bottom brackets use smaller bearings that wear faster or flex more under load. Dual-row bearings are one way around the space limit: they spread load across two rows inside a compact cup. That is a real advantage for riders who put out high torque or ride in gritty conditions, but it also means the bottom bracket is specific to the shell and crank it was designed for. Check the crank spindle diameter before assuming a dual-row unit will work.
When a threaded conversion is the better call
If your frame's press-fit shell is worn, creaking, or out of tolerance, a threaded conversion bottom bracket can be a more durable long-term fix because it threads into an adapter rather than pressing directly into the frame. That route adds parts and cost, and it is not necessary on a healthy shell. For a new build or a frame in good condition, a direct press-fit unit is simpler and lighter.
Decision rules for choosing a press-fit bottom bracket
- Measure the shell inner diameter first: Use calipers or a shop gauge to confirm the frame's press-fit bore. If it measures 41mm, the e*thirteen BB92 is in the running; if it is a different diameter, stop and look for a bottom bracket built for that bore.
- Match the shell width to the bottom bracket's listed range: Confirm your frame is BB89.5, BB92, BB107 or BB121 before buying the e*thirteen unit. A shell outside that list needs a different bottom bracket, not a spacer workaround. Write the shell width on your shopping note before you compare models.
- Confirm crank spindle diameter: The e*thirteen BB92 is for e*thirteen cranks with a 30mm spindle. If your cranks use a 24mm spindle, choose a bottom bracket designed for that spindle instead.
- Choose dual-row bearings when durability matters more than weight: If you ride hard, often in wet or gritty conditions, the extra bearing row is worth it. If you are building a weight-first race bike and your shell is healthy, a simpler press-fit unit may be enough.
- Inspect the frame before pressing anything in: A worn or out-of-round shell will creak regardless of bearing quality. If the bore is damaged, plan for a threaded conversion rather than forcing a press-fit cup. Have a shop check bore roundness if the frame is used.
Product facts
- Non-Threaded Bottom Bracket: Uses dual-row bearings and fits 41mm ID press-fit frames with BB89.5, BB92, BB107 or BB121 shells. It covers several common press-fit widths, but you still need to confirm your shell is 41mm ID and your crank uses a 30mm spindle.
Non-Threaded Bottom Bracket - Non-Threaded Bottom Bracket: A center tube helps seal the bottom bracket shell. That reduces contamination from water and grit entering the frame cavity, which is a common cause of press-fit creaking.
Who this bottom bracket suits
Best for
- Riders with a 41mm ID press-fit frame in BB89.5, BB92, BB107 or BB121 width
- e*thirteen crank owners with a 30mm spindle
- Riders who want extra bearing support in a narrow shell
Not for
- Frames with a threaded bottom bracket shell
- Cranks with a 24mm spindle
- Frames with a shell diameter other than 41mm ID
