Shell Bb30a vs Shell Bbright: specs compared
Updated 05 September 2026.
4
specs differ
Shell Bb30a and Shell Bbright differ on 4 specs: shell inside diameter, shell width, thread, crank spindles it hosts.
| Spec | Shell Bb30a | Shell Bbright |
|---|---|---|
| Type | press fit | press fit |
| Shell inside diameter | 42 mm smooth press-fit bore | 46 mm smooth press-fit bore |
| Shell width | 73 mm (asymmetric, 5 mm wider on the non-drive side) | 79 mm (asymmetric, offset 11 mm to the non-drive side) |
| Thread | none, two bearings press directly into the 42 mm bore | none, cups press into the 46 mm bore |
| Crank spindles it hosts | 30 mm native; 24 mm Shimano and 28.99 mm DUB need a reducer | designed around a 30 mm spindle; 24 mm and 28.99 mm cranks need a reducer BB |
Questions and answers
How do Shell Bb30a and Shell Bbright compare?
Shell Bb30a and Shell Bbright differ on 4 specs: shell inside diameter, shell width, thread, crank spindles it hosts.