Originally Posted by
CliffordK
I believe the Shimano cartridge bearings, wear them out and they're done.
Other brands have what appear to be replaceable sealed bearing cartridges, so they could be replaced over and over.
I believe the 75 has the Campy standard taper (ISO?), not the Shimano taper (J something, JIS?). My fix gear guru will beat me to a pulp if I try to go Shimano with Sugino 75s but will happily sell me a Miche BB (and which has worked for me very well over the past 4 years and 10k miles.
Outside of that prototype perhaps being track oriented and maybe not having very good seals (seals having friction and dirt being illegal on a track and infield!) that BB is probably up to all of Sugino's high standards and almost certainly a very good unit. 109 mm sounds to the top of my head to be a good number for a proper fix gear chain line with a 68 mm BB shell, so give it a try. If it's not a good chainline, give Miche a try.
Ben