This video uploaded by youtuber Peak Torque shows a Hambini BB having it’s engineering tolerances judged. Some key points
- It’s a BB86 Shimano Racing Edition Bottom Bracket
- The bottom bracket tolerances are accurate to 0.005mm, that is less than the diameter of a human sperm cell.
- The eccentricity was found to be 0.010mm (0.0005inch), and the recommended tolerance was 0.1mm. It was therefore 10 times more accurate than the specification allows.