GuyBoden
Guru
- Location
- Warrington
What I find interesting, is that the superior BB-UN55 uses loose ball bearings in a sealed unit, not cartridge bearings like most newer BB.
A picture of the internals of a Shimano BB-UN55.
Below is a pic of a typical cartridge bearing that's on each end of newer BB's axle.
A picture of the internals of a Shimano BB-UN55.
Below is a pic of a typical cartridge bearing that's on each end of newer BB's axle.
![ss-mr22317-2rs-0.jpg](https://www.kineticbikebearings.com/media/catalog/product/cache/84f461b372fe8ea5c09d2f85cf6efa75/s/s/ss-mr22317-2rs-0.jpg)