What type of bottom bracket do I have?

I'm looking for a video on how to service my bottom bracket but I'm not sure what type I have.

I have a Cannondale CAAD8 from 2011 with a Shimano 105 groupset.

Here are some photos: bottom bracket 1 bottom bracket 2 crank1 crank2

  • +1 for the excellent photos. But wash your bike - white shows everything :-\
    – Criggie
    Mar 23, 2019 at 6:12

1 Answer 1


The crankset is a BB30 FSA Gossamer with a 30mm spindle. There are four bottom brackets that will fit this crankset which might be in your bike. Thes are BB30(68/42), BB30a(73/42), PF30(68/46) and PF30a(73/46). To determine which one you need, there are two things to measure. First measure the inner shell diameter. 42mm is BB30/BB30a, while 46mm is PF30/PF30a. Measure the shell width to determine if yours is 68 mm or 73mm. If it's 68mm, then you need either the BB30 or PF30 (as determined by previous measurement). If it's 73, then you need either the BB30a or PF30a (as determined by previous measurement).enter image description here

  • I was mistaken. I had thought that PF30 was just the pressfit version of BB30. I'll amend my answer now. Mar 22, 2019 at 12:17
  • 1
    'BB30' printed on the drive side crank was a real giveaway! Mar 22, 2019 at 15:11
  • Thanks - there's also a great big sticker on the underside of the down tube saying BB30 - now I know what that means.
    – Mr_Thyroid
    Mar 23, 2019 at 20:07

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