Shimano UN7* series of bottom brackets were part of their top, or nearly top of the range groupsets for road and mountain bikes through the 90s. With a hollow axle, sealed bearings and aluminium cups they were lightweight yet reliable and came in a wide range of threadings and axle lengths for different frames and chain sets.
- Model: BB-UN72
- British thread (1.37 x 24) for 73 mm BB shells
- 113 mm long JIS axle
- Weighs: 250 grams
- Suits most Japanese made 90s road double chainsets
- Mid 90s
- Made in Japan