Joined: Feb 2012
Posts: 19,349
Likes: 5,466
From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
There are two possible designs which could be called "cartridge". There's the current tapered square (or ISIS or Octalink) BBs with some form of bearings but with a housing containing all but the second threaded retaining "cup". The Shimano UN series is a popular example. The other possibility is any BB that uses bearings of a cartridge design (often being simple radial contact ones, often poorly called "sealed" bearings). This might also be contained in a housing like the first example or might be made of separate parts. The current BB30, PFBB30 et all are examples.
This second design has been around for many decades, long before Phil introduced theirs. Andy