The BSA threaded bottom bracket is probably one of the easiest to recognize as it has a thread on the inside of the frame in between the bearings. Your frame will also have an integrated thread on the inside where the bottom bracket was screwed on. The inside diameter of the thread is approximately 37 millimeters. If this is what you can recognize on your own frame/bottom bracket, you know that you need one of our BottomThread models, a further explanation of which BottomThread can be found further below in this buyer's guide.
The PF86 and PF92 types are both PressFit type brackets, which means that the bracket is pressed into the frame. They can be recognized by NOT having a thread on the outside and having a very tight fit in your frame. The bearing is pressed into a composite cup, and this combination is then pressed into the frame. This bottom bracket type has, just like the PF30 only a very narrow part of the bottom bracket on the outside of the frame. This immediately shows that you have a PressFit bottom bracket. the PF86/92 can be recognized by an inside diameter of the frame of 41 millimeters. and a width of 86 mm or 92 mm.
BB30, or also called PF42 is also a PressFit type bottom bracket and thus no thread on the outside of the bottom bracket. This type of bottom bracket is also quite easy to recognize as it does NOT have threads and does NOT have removable cups between the bearings and the frame. The bearings are directly pressed into the frame. The inside diameter of the frame is 42 millimeters.
PF30 is also a PressFit type bottom bracket and thus no thread on the outside of the bottom bracket. It uses the same bearings as BB30. The only difference is that there is a cup in between the frame and the bearings for battery durability. The inside diameter of the frame is 46 millimeters.
Hollowtech II - 24 mm spindle
A Hollowtech II crank axle is quite easy to recognize. The outside diameter of the axle must be 24 millimeters along the entire length of the spindle. This standard has the widest frame compatibility on the market and is also the most popular used standard by many brands.
A GXP crank axle is also quite easy to recognize. The outside diameter of the axle is 24 millimeters, just like the Hollowtech II, but it is stepped down to 22 millimeters. This system "Clamps" the entire crankset on the left bearing in the frame, which prevents any form of side play and less- to no spacers are required! In the illustrations above you will see the difference between a Hollowtech II and a GXP crank axle.
BB30/PF30 - 30 mm spindle
30 mm cranks generally have a stiffer spindle even though they are made out of aluminum instead of steel. This makes the spindle slightly lighter. An outside diameter of 30mm indicates that you have a PF30/BB30 spindle. Another easy recognition point is the fact that the PF30/BB30 spindle is often attached to the non-drive side. That means that when you take everything apart, the axle is not attached to the side where the chain sits, but it is attached to the other crank.
A DUB axle tries to be the best of both worlds, giving a wider frame compatibility with the stiffness of the oversized 30 mm spindles. It has an outside diameter of 29 millimeters (28,99 millimeters to be precise). Besides that, the name DUB is noted on the spindle. Another easy recognition point is the fact that the DUB spindle is always attached to the non-drive side. That means that when you take everything apart, the axle is not attached to the side where the chain sits, but it is attached to the other crank.