The Shimano BB91 Press Fit Bottom Bracket Mountain-42A fits mountain frames with a bottom bracket shell width of 84.5mm, with a 42mm internal diameter. Use only Shimano Hollow Tech II cranksets with this bottom bracket.
- Actual weight: 65 grams
- Fits Shimano Hollow Tech cranksets
- For BB shell widths of 84.5mm
- Press-Fit BB shells only (no internal threads)
- 42mm BB cup diameter