Modern bottom brackets are classified in three different ways: Shell interface, shell width, and spline. Shell interface and width are dependent on your frame while spline is dependent on your crank. All of our frames are English threaded. The Campeur, Pass Hunter, Polyvalent, and Camargue all use the standard road shell width of 68mm. The Piolet uses a 73mm shell to allow for larger tire clearances and mountain components. All of our cranks are JIS square tapered.
Besides the standard English threading, and other nationality based threading patterns (discussed in the previous post), other shell interfaces include:
-336EVO - 46mm diameter, 87mm width
-BB30 - 42mm diameter shell
-BB86 - 41mm diameter shell, road bikes
-BB89.5 - 41mm diameter shell, 89.5mm width
-BB90 - Trek, bearing cartridges sit directly in frame
-BB92 - 41mm diameter shell, mountain bikes
-BB95 - Trek, bearing cartridges sit directly in frame
-BB107 - 41mm diameter shell, 107mm width
-BB121 - 41mm diameter shell, fat bikes
-BBright Direct fit - Cervelo, offset from the center plane, 79mm wide, 42mm diameter
-BBright Press fit - Cervelo, offset from the center plane, 79mm wide, 46mm diameter
-PF30 - 46mm diameter shell
-PF41 - 41mm diameter shell
Please note: in the BB# naming system, the # can refer to the spindle diameter, shell diameter, or shell width.
All of these are threadless, but that doesn't mean they're compatible with our threadless bottom bracket. Most are wider shells for larger spindles and bigger bearings. Threadless shells have been around for a while. Merlin frames had their own threadless shell.
You can try the new T47 standard if you want the advantages of a large diameter, but without the creaking and noise associated with threadless shells. According to press releases, the T47 should "yield a much higher interface success rate."
Bottom bracket shell widths range anywhere from 61 to 132mm. The wider stuff is generally for fatbikes and larger tire clearances. Getting a drivetrain to clear those large tires has been a challenge in the bike industry lately. The solution is usually a combination of thiner chainstay, wider bottom bracket, wider rear, and larger Q factor.
Last is the spindle interface. A few of these include:
-386 EVO - like BB30 but requires a longer spindle
-BB30/PF30 - 30mm diameter spindle
-BBright - crank must accomodate offset
-Campagnolo Power Torque - outdated Campy system
-Campagnolo Ultra Torque - current Campy system
-FSA Mega Exo - downhill, extra bearings, there are several versions of this system
-Hive Polygon - it's not a polygon, it's a rounded triangle
-ISIS - it came out before the other ISIS went mainstream
-RaceFace Cinch 30mm - oversize spindle
-Rotor 3D+ - oversize spindle
-Shimano Hollowtech II - current Shimano standard
-Shimano Octalink VI - no longer used for cranks, but I think you can still get bottom brackets
-Shimano Octalink V2 - same deal, replaced by Hollowtech
-TruVativ GXP - SRAM for 2 piece cranks
-TruVativ Howitzer - oversized for downhill
-TruVativ HammerSchmidt - HammerSchmidt was revolutionary
-TruVativ Power Spline - functionally similar to a square taper but with a proprietary spline
-Zipp Vuma - I think this is some kind of aerobics class
The ones you should know (besides square taper) are Shimano Hollowtech II and Campagnolo Ultra Torque. Hollowtech II is compatible with some other stuff. For example, newer models of the FSA Gossamer crank can use a Shimano Ultegra Hollowtech II bottom bracket. I have this on my cross bike. Campagnolo Ultra Torque is certainly less common (if not exclusive to Campagnolo cranks), but new Campy is still cool. Everything else is garbage.
Some other bottom brackets standards and technologies not discussed in this post include
-BB7 - these are brakes
-BB8 - this is a robot
-BMX - designed for impact and stunts
-CF69 - I made this up
-Eccentric - they're a bit off center
-Freewheel - featured on some old Schwinns
-Tandem - usually eccentric
Some of the new bottom brackets have their advantages. Some introduce new problems. Most are designed for stiffness. Maybe someday we'll change, but the square tapers still work.