Let’s slap a BB30 sticker on it!
Before we get started, there is a good chance your Cannondale frame has a BB30 logo on the down tube. Cannondale is the company that invented the BB30 standard in the early 2000s and they printed a gazillion stickers that they are still trying to get rid of today. Ignore it. There is no guarantee your frame is actually a BB30 frame.

What’s with the A?
The A in BB30A and PF30A stands for Asymmetric. The bottom bracket shell is made 5mm wider on the non-drive side only. According to Cannondale it makes the system wider and stiffer. Other benefits include making shorter seat stays and helping with the Ai, Cannondale’s off center rear triangle and wheel system.

BB30A vs PF30A
One new standard is great, two is better! in 2015 the Synapse started using BB30A (bearings pressed direct in the frame), the Slice TT bike started using PF30A (bearings pressed in a cup, then pressed into the frame). The width dimensions are the same, only the diameter of the frame opening is different: 42 vs 46mm. Typically a BB30 shell is made of aluminum, where a PF30 shell can be made out of all carbon.

We need more standards!!
As if two new standards, exclusive to Cannondale was not enough, the guys in Connecticut decided to add 2 more. In 2017 the new SuperX cyclo cross bike came out with BB30A83: same as BB30A except at 83mm width instead of 73mm.

In 2018 the Scalpel Si cross country race bike seems to have PF30A83, Same as PF30A, only wider by 10mm. Even though the numbers seem the same, this is does not use the same crank set or spindles as the SuperX. Mountain bike crank sets are traditionally 5mm wider than road crank sets. Are you still with me?

Why, why, whyyyyyyy?
The result of all this innovation is that it is virtually impossible to fit an aftermarket crank set on a Cannondale frame. If you want to transfer your power meter from another bike: tough luck!

Kogel Bearings and other bottom bracket manufacturers have designed conversion bottom brackets for the most common asymmetric frames. A standard that is only used on one model of CX frame does not sell in enough volume to justify the tooling and production cost for aftermarket products. Sorry Johnny, no Shimano or Quark crank set for you.

Cannondale is a company that strongly believes in system integration. They will design every part of the bike to what they think is the best fit. From a suspension fork with only one leg to wheels that are purposely built with the rim off-center. Cannondale produces crank sets and all these confusing bottom bracket standards force their customers to use theirs over a third party product.

What’s the standard of my frame?
I have tried to make a comprehensive list of all Cannondale frames that use the asymmetric standards below. I think it is accurate, but if you see any mistakes or updates, feel free to bring them to my attention with the contact button at the left bottom of your screen.

BB30A (73mm width, 42mm Inner Diameter) is used on
• Synapse 2015 and later
• Caad12
• Slate

PF30A (73mm width for road bikes, 78mm width for MTB, 46mm Inner Diameter)
• Slice 2015 and later
• SuperSix Evo HiMod 2016 and later
• FSi

PF30A83 (road edition)
• SuperX 2017

PF30A83 (MTB edition)
• Scalpel Si