SHIMANO UN55 BB Square Taper Bottom Bracket Review Posted by Pelicandy October 1, 2018 in Drivetrain Components Bottom Bracket Fit – 68mm BSA of ENG Sealed cartridge bearings The Shimano BB-UN54/55 Square Taper bicycle bottom bracket gives you reliable strength for square tapered cranksets. Random Products Funn ZIPPA BASH (26T-32T) Review RaceFace 9/10/11-Speed Single Ring Review OneUp Components 94/96 Round Chainring, 94/96BCD 3... CRANKSET FSA GOSSAMER 386EVO 175×50/34T w/oBB... Cycling Outdoor Recreation Parts & Components SHIMANO Sports & Outdoors