We have threaded adapters for any width bottom bracket from 68mm to 120mm for most press-fit standards. If you have a 68 or 73mm bottom bracket you may have the best results with the one-piece adapter. PF42 refers to the 42mm inside diameter of the shell. PF42 is used in BB30, BB30A, BB30AI, and BBRIGHT™ DIRECT FIT bottom bracket types. PF46 refers to an inside shell bore diameter of 46mm. PF46 (PF30, PF30A, PF30AI, BB386EVO, OSBB, BBRIGHT™ PRESS FIT bottom bracket types. PF41 BB shells have a nominal 41mm inside diameter. PF41 (BB86, BB89.5, BB92, BB107, SHIMANO® PRESS-FIT, PF24 bottom bracket types. Eccentric BB Adapter - American (Ashtabula) BB shells 51.3 mm (2.02") inside diameter. These are typically found in older American-made bikes and American children's bikes. Some cruiser bikes for the American market still use this style. Note: (Adapt your bottom bracket to the BSA/JIT English threaded type that mid-drive motors require. Most bikes that originally sold for less than $1500 or are older than 2013 have English threaded bottom brackets and you are good to go. If you have a square tapered spindle for your cranks then you have the required threaded bottom bracket. Around 2012 many higher-end bikes started being fitted with various press-fit bottom brackets many of which can be adapted to English threaded so you can still do a mid-drive motor conversion on them. However, there are some exceptions. For an in-depth article on adapting various bottom brackets and the exceptions see this thorough article by Matt Hughes.) EBC recommends using Loctite 641 or other sleeve retaining compound on the adapter and on the inside of the BB shell case before installing to help keep the bottom bracket solid and to keep some motors like Bafang from rotating. Use Loctite 7649 spray for a quick set if you are going to ride it the same day.
