The BSA (English threaded) bottom bracket is the workhorse of cycling — and the place where ceramic bearings deliver the biggest watt savings. Our BSA Shimano BB pairs Grade 3 silicon nitride balls with DLC-coated chromium steel races inside precision-machined 6061 aluminum cups. Measurably lower friction, a buttery-smooth pedal stroke, and bearing life measured in years. Threads into any standard 68mm BSA shell. Designed specifically for Shimano's 24mm Hollowtech II spindle.
What You Get
- ✓ Biggest watt savings on your bike — BB friction matters most
- ✓ Grade 3 Si₃N₄ ceramic balls with DLC-coated races
- ✓ Precision-machined 6061 aluminum cups, black anodized
- ✓ Dual-lip seals keep out water and grit
- ✓ Standard BSA thread — installs with any BB tool
- ✓ Designed specifically for Shimano 24mm spindle
Technical Specifications
| Weight |
78g |
| Seal Type |
Dual-lip contact seals |
| Tolerance |
ABEC-7 |
| Cup Material |
6061-T6 Aluminum, anodized |
| Expected Life |
20,000–30,000 miles |
| Race Material |
52100 Chromium Steel, DLC Coated |
| Shell Standard |
BSA (English thread, 68mm) |
| Bearing Material |
Grade 3 Silicon Nitride (Si₃N₄) |
| Spindle |
24mm (Shimano Hollowtech II) |
Compatibility
Shimano Dura-Ace FC-R9200 / FC-R9100
Shimano Ultegra FC-R8100 / FC-R8000
Shimano 105 FC-R7100 / FC-R7000
Shimano GRX FC-RX820 / FC-RX810
Shimano Tiagra / 105 (4700/5800)
FSA MegaExo (24mm)
Rotor Aldhu / Vegast (24mm)